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Review

Mesenchymal Stromal Cells: Heterogeneity and Therapeutical Applications

Institute for Transplantation Diagnostics and Cell Therapeutics, University Hospital Düsseldorf, 40225 Düsseldorf, Germany
*
Author to whom correspondence should be addressed.
Cells 2023, 12(16), 2039; https://doi.org/10.3390/cells12162039
Submission received: 29 June 2023 / Revised: 6 August 2023 / Accepted: 8 August 2023 / Published: 10 August 2023
(This article belongs to the Collection Exclusive Review Papers in 'Stem Cells')

Abstract

:
Mesenchymal stromal cells nowadays emerge as a major player in the field of regenerative medicine and translational research. They constitute, with their derived products, the most frequently used cell type in different therapies. However, their heterogeneity, including different subpopulations, the anatomic source of isolation, and high donor-to-donor variability, constitutes a major controversial issue that affects their use in clinical applications. Furthermore, the intrinsic and extrinsic molecular mechanisms underlying their self-renewal and fate specification are still not completely elucidated. This review dissects the different heterogeneity aspects of the tissue source associated with a distinct developmental origin that need to be considered when generating homogenous products before their usage for clinical applications.

1. Introduction

Mesenchymal cells were first discovered almost 60 years ago by Friedenstein et al. in the bone marrow of guinea pigs and were first described as in vitro colony-forming fibroblasts (CFU-Fs) [1]. These were characterized by their high replicative capacity and their ability to give rise to different cells of the non-hematopoietic lineage and to form osseous tissue in vivo. The term “mesenchymal” was adopted in the 1990s based on their multi-lineage differentiation capacities into mesodermal cell lineages both at population and clonal levels [2]. Maureen et al. suggested using the term “stromal stem cells” to distinguish them from histogenetically distinct hematopoietic and endothelial cells and to underline their capacity to maintain hematopoietic stem cells (HSCs) in the bone marrow [3]. The International Society for Cellular Therapy (ISCT) recommended the term “mesenchymal stromal cells” to avoid potential confusion, since the commonly used term “stem cell” should be reserved for the subset of cells possessing stem cell activity, designated by stringent and generally accepted criteria [4]. Bianco et al. elucidated in a large review the definition and functional identification of a mesenchymal stem cell-based on functional assays [5]. The main marker for the identification of a mesenchymal stromal cell was defined as the in vivo generation of heterotopic “ossicles” [5].
Due to their self-renewing capacity, their highly proliferative state, and their differentiation potential into cells of mesenchymal tissues including bone, fat, and cartilage, MSCs have gained growing attention in the last decade in the fields of tissue engineering and cell therapy (Figure 1). They became an attractive source in clinical applications for the regeneration of damaged tissues and the treatment of a broad range of human diseases [6].
Soon after their first isolation, MSCs became one of the most controversial areas in the field of stem cell biology. This is due to the complexity of their anatomical identity, heterogeneity, phenotype diversity, tissue distribution, lineage, and function. Nowadays, two different definitions of “MSCs” can be found in the literature. One that considers “MSCs” as cultured bone marrow stromal cells, which are progenitors specific to the bone marrow and not found elsewhere, characterized by their multipotency to exclusively form cells of the skeletal tissue and by their self-renewing capacity [5]. An important function of this progenitor cell is the maintenance and regulation of hematopoiesis, thus forming the hematopoietic stem cell niche in the bone marrow, which additionally gives structural support, facilitates migration, and regulates endocrine function [5,7]. The second definition considers “MSCs” as a range of progenitor cells that can differentiate into different lineages in vitro and reside beyond the bone marrow and the skeletal tissues [6,8,9].
MSCs can be harvested without major ethical concerns and have been shown to promote endogenous tissue repair and regeneration. This is largely related to their paracrine and immunosuppressive activities resulting in the alteration of the host immune response upon transplantation [10]. In consequence, various experiments and trials emerged showing the efficacy and effectiveness of MSCs as a promising alternative to conventional immune suppressants for the reduction of the progression of the graft-versus-host disease (GvHD), for example in the case of hematopoietic stem cell transplantation or in patients with severe treatment-resistant GvHD of the gut and liver [11].
Bone marrow-derived MSCs (BM-MSCs) were shown to modulate innate and adaptive immune responses [12]. Generally, several studies demonstrated the ability of MSCs to suppress T cell proliferation and pro-inflammatory cytokine secretion [13], dendritic cell maturation and their differentiation from monocytes through secretion of prostaglandin E2 (PGE2) and interleukin 6 (IL-6) [14,15]. Moreover, BM-MSCs were shown to interact with natural killer cell (NK cells) by inhibiting interleukin 2 (IL-2) induced proliferation of resting NK cells and partially inhibiting NK cell proliferation thus increasing their cytotoxicity [16]. Others reported that MSCs can interact with macrophages, thus increasing their adhesion to T cells and indoleamine 2,3-dioxygenase (IDO) expression and resulting in increased immunosuppressive capacities [17]. B cell proliferation can also be modulated by MSCs [18], which were shown to inhibit B cell terminal differentiation [19] and apoptosis [20]. However, the exact underlying mechanisms of action supporting the control of aberrant immunosuppressive responses remain to be elucidated.
MSCs were also used for stem cell therapy of heart diseases such as myocardial infarction [21], pulmonary arterial hypertension [22] and coronary heart disease [23], as transplanted MSCs are able to engraft and differentiate into cells of the cardiac tissue e.g., cardiomyocytes and vascular cells. This is confirmed by an increased expression of the cardiac marker troponin T [24]. Moreover, they secrete paracrine factors that benefit cardiac repair by their immunomodulatory [25] and anti-fibrotic effects [26], but also through promotion of neovascularization [27].
In this comprehensive review, we aim to address several aspects of MSC heterogeneity, which forestalls their full exploitation in clinical application. Examples of current MSC advances and applications in clinical trials are presented.

2. Donor-to-Donor Heterogeneity

MSCs have been shown to display a high donor-to-donor biological heterogeneity, which should be taken into consideration for large-scale expansion. MSCs derived from 17 healthy bone marrow donors showed discrepancies in various aspects including osteogenic potential capacity, expression of alkaline phosphatase and growth rate [28]. These differences might additionally be enhanced by distinct factors including donor age, sampling bias during marrow aspiration and cell expansion conditions [29]. Donor-dependent heterogeneity is also related to the difficulty of the identification of MSCs, which is caused by the lack of unique and distinct cell features and the broad range of morphological properties. The subpopulations with distinct morphologies might also differ in their intrinsic properties. Given this heterogeneity within the same species, tissue, population and donor, which is partially responsible for the incongruence of the MSC-based clinical data, the ISCT additionally defined minimal criteria to characterize MSCs and minimize differences between laboratories worldwide. They were defined by their ability to adhere to plastic under standard culture conditions, by the expression of following surface markers: CD44, CD90, CD105, CD73 and by the lack of expression of the hematopoietic markers CD11b, CD14, CD19, CD34, CD45, CD79 and HLA-DR surface markers (Table 1) [9]. Furthermore, MSCs must possess the in vitro differentiation ability into chondrocytes, osteocytes and adipocytes [9].
Donor age is an important parameter that affects the functionality of MSCs, including their differentiation potential, self-renewal capacity, immunomodulatory properties, and tissue repair capacities if MSCs are harvested from the bone marrow. MSCs collected from older donors are characterized by a high amount of senescent and apoptotic cells, correlating with slow proliferation rates and population doubling times [9]. In addition, donor age negatively influences the ability of MSCs to form osteoblasts and weakens their repair capacity through the reduction of the immunomodulatory effects and the response to oxidative stress in comparison to cells harvested from younger donors. Kanawa et al. found that human BM-MSCs harvested from older donors showed a decreased chondrogenic potential along with a decreased expression of glycosaminoglycans (GAG), Sox9, collagen II, and aggrecan but did not affect the osteogenic or adipogenic potentials [30]. Other groups reported a decreased adipogenic and osteogenic potential of BM-MSCs with increasing donor age, with no changes in the chondrogenic differentiation potential [31,32].
Siegel et al. compared human BM-MSCs isolated from 53 different donors (25 female, 28 male; age: 13 to 80 years) and showed differences in phenotypes, with higher levels of CD71+, CD90+, CD106+, CD140b+, CD146+, CD166+, and CD274+ subpopulations in samples from younger donors [32]. These markers, however, did not correlate to donor age on the transcriptional level [32,33]. No correlation of donor age with the multi-lineage differentiation potential of the BM-MSCs could be confirmed [32].
Mareschi et al. isolated and expanded MSCs from the bone marrow of pediatric and adult donors to compare their replicative capacity [34]. They showed no differences in morphology, whereas the cell growth was strictly dependent on the donor´s age, with a twice higher population doubling time in the pediatric population compared to the adult cells. Psaroudis et al. compared the levels of expression of the senescence marker CD26, also known as adenosine deaminase complexing protein 2, in MSCs isolated from the adipose tissue of adult and pediatric donors [35]. This showed that CD26 expression and, accordingly, senescence levels were higher in early passage adult MSCs compared to pediatric MSCs. Moreover, enrichment of CD26 was shown to correlate with impaired immunopotency, i.e., MSC inhibition of proliferating T cells.
In addition to donor age, health status, and functional deficiencies, basic treatment (with, e.g., corticoids) of patients can also affect the efficacy of autologous or allogeneic MSC treatment.
MSCs harvested from multiple sclerosis patients showed similar osteogenic and adipogenic differentiation in vitro. This, however, comes with higher senescence, low secretion levels of anti-inflammatory cytokines including interleukin 10 (IL-10) and the transforming growth factor β (TGF-β), modulation of the fibroblast growth factor (FGF) and the hepatocyte growth factor (HGF) signaling pathways. Moreover, they showed decreased inhibition of T cell proliferation compared to healthy individuals [36]. These alterations could not be reversed by autologous hematopoietic stem cell transplantation [36]. Bone marrow-derived cells isolated from patients with myelodysplastic syndrome displayed reduced clonality and growth, elevated senescence, altered osteogenic and adipogenic differentiation potentials, and also abnormal phenotypical characteristics such as higher expression rates of CD29 and CD166 in comparison to healthy MSCs [37]. Adipose-derived MSCs from obese patients showed altered plasticity, manifesting itself in a changed pattern of surface markers both before and after differentiation, including the higher expression of CD106 and HLA-II, the lower expression of CD29, and a decreased cell proliferation and differentiation potential compared to MSCs isolated from lean donors [38]. This might result from the latent effects of the obesity-related hypoxia environment [38].
A similar pattern in terms of altered multipotency was observed in experiments with obese mice, thus supporting the hypothesis that this might be regulated by the increased systemic levels of free fatty acids and further obesity-related cytokines [39].
MSCs derived from the bone marrow of osteoporosis patients revealed a similar morphology and surface markers compared to cells isolated from healthy individuals and, at the same time, lower proliferation rates in response to insulin-like growth factor-1 (IGF1) and a deficient osteogenic potential due to an upregulated expression of alkaline phosphatase and calcium phosphate deposition [40]. MSCs derived from osteoporotic donors were characterized by impaired expression and maintenance of collagen type I in the extracellular matrix; there were up to 50% fewer cells compared to healthy donors, combined with higher levels of gelatinolytic activity and decreased expression of TGF-β1, thus leading to a stronger adipogenic differentiation potential [41].
Donor gender-related differences were also reported, i.e., female BM-MSCs were found to have higher population doubling times than male BM-MSCs, with a significant correlation between doubling time and donor age in contrast to cells isolated from male donors [42]. Additionally to differences in the proliferation capacity and cell yields, a study conducted with human MSCs isolated from Wharton´s jelly (WJ-MSCs) showed gender-related differences in the gene expression patterns in terms of a decreased expression of the tumor necrosis factor receptor 1 (TNFR1) and the pro-inflammatory cytokines tumor necrosis factor α (TNFα) and interleukin-1 β (IL-1β) in the female cells [43]. Other groups suggested that female MSCs secrete more anti-inflammatory and pro-angiogenic factors in comparison to male MSCs and thus have a greater therapeutic capacity for vascular remodeling and reducing neonatal hyperoxia-induced lung inflammation [44]. Moreover, female BM-MSCs revealed decreased adipogenic differentiation potential with increasing donor age in comparison to their male counterparts [42]. These findings indicate the necessity of considering donor characteristics, in particular age and gender bias, when selecting MSCs for allogeneic transplantation for meaningful therapeutic outcomes.

3. Tissue Source-Dependent Heterogeneity

MSCs currently used in the field of tissue engineering or other clinical applications can be isolated from different tissues such as the bone marrow, adipose tissue, cord blood, umbilical cord, synovial membrane, lung periosteum, dental pulp, and others (Table 2) [45]. Depending on their source of isolation, MSCs show disparities in their phenotype, proliferation, differentiation capacity, immunomodulatory properties, transcriptional profiles, and proteomic profiles. Unfortunately, biological properties mainly in the skeletal system are based on in vitro assays using cultures that are chemically directed towards osteogenic, chondrogenic, and adipogenic differentiation employing strong induction [9]. Therefore, these tests are not stringent and fail to predict the in vivo differentiation potential of MSCs derived from different tissues. Depending on their tissue source, differentiation of MSCs into osteogenesis, chondrogenesis, or adipogenesis might not even be the correct biological function.
Isolation of MSCs from adult tissues such as the bone marrow encounters several limitations, such as low cell numbers, age- and donor-dependent differences, limited donors, and limitations to autologous use. MSCs isolated from fetal tissue have several advantages over adult MSCs in terms of availability (higher cell numbers and frequency) and cellular proliferation, with lower senescence levels and faster population doubling times [46]. Moreover, their differentiation capacity, though heterogeneous between the different fetal sources [47], is superior compared to adult MSCs, for example, higher basal expression of 16 osteogenic genes in correlation with higher in vitro calcium production [46,48], colony-forming capacity [46], and paracrine effects.

3.1. MSCs from Adult Sources

3.1.1. Bone Marrow-Derived MSCs (BM-MSCs)

With regard to their differentiation potential, BM-MSCs are considered to have a higher tendency to differentiate into osteoblasts [49,50] and into bone and cartilage in vivo [5,51]. This was recently confirmed by Hochmann et al. [52] and can be additionally modulated in vitro by cell culture under hypoxic conditions [53]. In the context of tendinopathy treatment, BM-MSCs appear to be the most suitable source since they show an increased expression of various factors associated with tenogenesis, including collagen I, Scleraxis, and Tenomodulin [54].
BM-MSCs are also the most studied cells in the field of cartilage regeneration. The reason for this is the higher chondrogenic potential of cells isolated form the iliac crest and vertebral body in comparison to cells harvested from the femoral head [55]. Hochmann et al. investigated the molecular mechanisms underlying transcriptional stromal differentiation networks and showed that binding sites of commonly expressed transcription factors in the enhancer and promoter regions of ossification-related genes such as Runt and bZIP are only accessible in BM-MSCs and not in other extra-skeletal MSCs, thus suggesting an epigenetically organ-dependent and predetermined differentiation potential [52].
Moreover, BM-MSCs possess the shortest culture periods and the lowest proliferation rates and population doubling time in comparison to cells from other tissues [56], which is enhanced by the in vitro acquired culture-induced aging through gradual telomere shortening and amplified susceptibility to oxidative stress [57]. An additional major disadvantage of BM-MSCs consists of the negative correlation of their differentiation capacity with donor age, which could be inefficient when harvested from elderly patients [32].
BM-MSCs were shown to induce anti-fibrotic and anti-inflammatory events after transplantation into the renal sub-capsular area of rats that lead to renal fibrosis reversal and promotion of renal morphological restoration and remodeling, which is achieved by the reduction of collagen deposition, macrophage accumulation, TNF-α reduction, increase of IL-10 expression, Bowman’s capsule, and tubule-interstitial basal membrane morphological recovery [58]. Moreover, they were shown to significantly inhibit allogeneic T cell proliferation through the expression of higher levels of IL-10, TGF-β1 and immunosuppressive cytokines [49]. Other studies also demonstrated the advantages of BM-MSCs in their ability to secrete higher amounts of stem cell-derived factor-1 (SDF-1), which is related to a stronger migration capacity, and HGF, which must be systematically considered during therapeutic applications to increase the efficiency of homing towards the injury site to induce tissue repair [59]. After transplantation in an immunodeficient mice model, BM-MSCs were shown to initiate defect bone healing through secretion of osteopontin, thus contributing to transient mineralized bone hard callus formation [52].
Several clinical trials using allogeneic or autologous BM-MSC injection or transplantation for treatment of various diseases (Table 3). Bolli et al. showed that transendocardial administration of allogeneic BM-MSCs was safe and tolerated by cancer survivors with anthracycline-induced cardiomyopathy, thus providing groundwork for future clinical studies [60]. Moreover, the immunomodulatory effects of BM-MSCs were used for treatment of patients suffering from ischemic injury in numerous clinical trials and have been proved to be beneficiary [61]. Additionally, new treatments have emerged using BM-MSCs for treatment of multiple sclerosis and have also been proved to be efficacious.

3.1.2. Adipose Tissue-Derived MSCs (AT-MSCs)

Adipose tissue is another alternative, less invasive source for the isolation of higher initial yields of MSCs than from the bone marrow, with higher proliferative capacity in vitro [57]. This was first described by Zuk et al. in 2001 [66]. AT-MSCs are isolated from the lipoaspirate obtained during several surgical processes, such as liposuction or lipectomy, which are considered as minimally invasive procedures [67]. They also constitute up to 3% of all cells in the adipose tissue [68,69]. Similar to BM-MSCs, it has been reported that donor age negatively affects the expansion and differentiation potential of AT-MSCs [70]. However, AT-MSCs have also been shown to secrete several factors that support tissue regeneration, such as vascular endothelial cell growth factor (VEGF) and HGF, thus having beneficial effects that can be used for cell-based cardiovascular gene therapy of ischemic tissue [71]. Todorova et al. demonstrated that AT-MSCs are more potent immune modulators of the differentiation of monocyte-derived dendritic cells in comparison to BM-MSCs [72], and others reported AT-MSCs to have a stronger suppressive effect in terms of T cell formation and activation [73].
AT-MSCs have emerged as an effective treatment for Crohn´s disease (CD), a condition characterized by chronic inflammation of the gastrointestinal tract with relapsing behavior, no known reasons, and no effective treatments. Allogeneic AT-MSCs have been used for the treatment of complex perianal fistulas in adult patients and are nowadays commercially available in Europe under the name AlofiselTM [74,75,76,77,78].
In comparison to BM-MSCs, AT-MSCs exhibit lower chondrogenic and osteogenic potentials [59,79]. However, they show a higher proliferative capacity [57,59,80], a later occurrence of cellular senescence [81], higher immunomodulatory effects, and an upregulated expression of different cytokines, chemokines and growth factors including interferon-γ (IFNγ), basic fibroblast growth factor (bFGF) and IGF-1 [59]. For these reasons, they are nowadays widely used in cartilage regeneration therapies.

3.1.3. Endometrium-Derived MSCs (E-MSCs)

After its first description by Prianishnikov in 1978 [82], human endometrial tissue has become an interesting MSC source for cell-based therapies due to its easy harvesting techniques without analgesic requirements. Several studies investigated the chondrogenic differentiation potential of E-MSCs for possible application in cartilage regeneration and showed that they could produce abundant amounts of sulfated glycosaminoglycans and type II collagen [83,84,85]. E-MSCs are also characterized for their reduced immunogenic and inflammatory properties in terms of low HLA-ABC and negative HLA-DR expression [86]. Moreover, they could inhibit proliferation, of mouse spleen lymphocytes and human peripheral blood lymphocytes during co-culture due to potential TGF-β1 secretion [86]. A new in vivo study conducted in mice showed that E-MSCs but not AT- or UC-MSCs, could suppress malignant endometrial cancer through inhibition of the Wnt/β-catenin signaling pathway by secreting high levels of Dickkopf-related protein 1 (DKK1) [87]. E-MSCs were also shown to possibly inhibit dendritic cell maturation and proliferation through increased expression of IL-6 and IL-10 [88].
These results suggest that E-MSCs have great potential and a promising future for clinical applications. However, only preliminary studies are available, and the lacking mechanisms of action still need to be elucidated.

3.1.4. Synovial Membrane-Derived MSCs (SD-MSCs)

The synovial, membrane or synovium, is the connective tissue that lines the synovial joint cavity. Bari et al. characterized, in 2001, MSCs isolated from the synovial membrane of human knee joints and reported their multi-lineage differentiation potential and in vitro expansion over at least 10 passages with limited cell senescence independently of donor age [89]. SD-MSCs are more accessible and can be extracted during knee surgery or joint aspiration in a minimally invasive procedure for autologous transplantation. Moreover, they have been shown to possess high proliferation rates, reduced immunogenicity through a reduced expression of HLA-DR in comparison to BM-MSCs, and a high chondrogenic potential in comparison with MSCs from other sources [90]. For this, they are studied for possible applications in osteoarthritis therapy by intra-articular injection [91] and in cartilage and meniscus regeneration. The promising potential of SM-MSCs in the treatment of osteoarthritis, which is caused by joint degradation with increasing age and has a higher incidence in females, has increased in the last decade [92]. Several studies reported a reversed osteoarthritis process, improvement of joint motility, cartilage quality, and pain relief [93,94,95,96].

3.1.5. Dental Tissue-Derived MSCs (D-MSCs)

MSCs were first isolated from dental pulp but can also be derived from several other adult dental tissues, including exfoliated deciduous teeth, periodontal ligament, apical papilla, gingiva, dental follicle, tooth germ, and alveolar bone. In addition to their ability to control the odontogenic differentiation potential, they are also known for their osteogenic, adipogenic, and chondrogenic differentiation capacities, as well as their transdifferentiation capacities into the ectodermal or endodermal lineages [97].
D-MSCs are increasingly being used in the field of regenerative medicine, with emerging evidence for their better and more impactful immunomodulatory properties. Previous reports showed that D-MSCs can suppress T cell proliferation, which might be suitable for usage during hematopoietic or solid-organ allogeneic transplantation [98]. D-MSCs also inhibited peripheral blood mononuclear cell (PBMNC) proliferation stimulated with mitogen or in an allogeneic mixed lymphocyte reaction (MLR), whereas co-culture with activated PBMNCs led to the upregulation of TGF-β, HGF, and IDO expression after stimulation with IFNγ [99]. The application of D-MSCs in preclinical studies and clinical trials for regenerative therapies for the treatment of dental diseases but also of neurodegenerative [97,100], autoimmune [98,101], and orthopedic [102] disorders is promising.

3.2. MSCs from Fetal Sources

3.2.1. Cord Blood MSCs (CB-MSCs)

Rubinstein et al. first reported in 1993 the use of frozen stored placental blood as an alternative source for hematopoietic stem cells for unrelated bone marrow reconstitution [103]. Within the last decades, placental cord blood has been widely established as a valuable source for both hematopoietic stem cells and mesenchymal stromal cells. Different groups did not succeed in isolating MSCs from cord blood in contrast to the bone marrow [104,105]. Others described methods for the successful isolation of MSCs from umbilical cord blood despite low cell frequency [106,107] and that could even reach in vitro differentiation into different lineages [108]. MSCs isolated from cord blood have been shown to have a unique chondrogenic differentiation potential in vivo and reveal higher replicative rates compared to BM-MSCs [51,57,109].
Several studies showed that CB-MSCs, compared to BM-MSCs and AT-MSCS, have a reduced adipogenic differentiation potential, which might be related to the vast amounts of pre-adipocyte factor 1 (Pref-1) in cord blood plasma, which confers CB-MSCs anti-adipogenic properties [110,111]. This can, however, be adjusted by negative regulation of the Wnt5a/β-catenin signaling pathway through exogenous calcium treatment [68].
In addition to CB-MSCs, cord blood also contains a population of previously named “unrestricted somatic stem cells” (USSC), which are characterized by the absence or marginal expression of all 39 HOX-genes in contrast to CB- or BM-MSCs [112,113]. In humans, the 39 HOX genes are located in four different clusters: A, B, C, and D, as first described by Krumlauf in 1994 [114]. While regulated HOX expression is important during embryonic and fetal development [115], Ackema and Charite described the HOX code for MSCs derived from different anatomic sites [116]. Our group was able to show that BM- and CB-MSCs expressed the HOX code in all four clusters, unlike USSCs [112]. This reflects the fact that the USSCs originate from a different biological niche during fetal development. Moreover, our group demonstrated that the expression levels of the δ-like 1/pre-adipocyte factor 1 (DLK-1/PREF1) also allows the distinction between USSCs and CB-MSCs [117]. Accordingly, when DLK-1/PREF1 was constitutively expressed in CB-MSCs, the adipogenic differentiation potential was impaired, whereas its silencing in USSCs allowed adipogenesis [117]. Subsequently, CB-MSCs and USSCs derived from cord blood must be clearly distinguished from umbilical cord-derived MSCs, since UC-MSCs fail to differentiate in vitro and in vivo towards bone and cartilage and also differ in their respective HOX expression patterns [118].

3.2.2. Umbilical Cord-Derived MSCs (UC-MSCs)

Similar to CB-MSCs, UC-MSCs can also be extracted without any ethical controversies from umbilical cord tissue after childbirth and display a four time higher proliferation levels compared to BM-MSCs and AT-MSCs [119]. In an attempt to characterize UC-MSCs, UC-derived primary cells with mesenchymal-like properties separated by counterflow centrifugal elutriation displayed several subpopulations differing in their sizes and proliferation potentials. These may be precursors of the mature populations or are probably connected to the amount of senescent cells in the respective populations [120].
Although UC-MSCs have different molecular chondrogenic and osteogenic signatures lacking substantial integrin-binding sialoprotein expression [121] and skeletal formation in vivo [118], UC-MSCs have been extensively used in clinical research related to neurodegenerative and cerebrovascular diseases, autism, spinal cord injury, and hypoxic ischemic encephalopathy (Table 4).
Intracerebral transplantation of UC-MSCs was shown to alleviate encephalopathy caused by neonatal hypoxia and ischemia in rat neonates by in vitro inhibition of apoptosis of injured neurons [122]. In hyperoxia-exposed rats, UC-MSCs lead to a greater improvement of alveolarization and less macrophage infiltration compared to BM-MSCs [123].
Min et al. determined that UC-MSCs can be potentially used for therapy of demyelinating diseases of the central nervous system since they could promote spinal cord re-myelination by suppressing neuro-inflammation through interaction with microphages and suppressing microglial cell interaction, resulting in a reprogramming of the immune response in a mouse model [124]. The exact molecular mechanism responsible for this interaction is, however, not yet resolved [124,125]. Other groups described the application possibilities of the re-myelination properties of UC-MSCs for the treatment of multiple sclerosis [125,126]. Wehbe et al. reported the usage of allogeneic UC-MSCs for the treatment of progressive and refractory scleroderma, with a combined immunotherapy approach resulting in a significant overall improvement [127].
Table 4. Examples of clinical trials of UC-MSCs for treatment of various conditions.
Table 4. Examples of clinical trials of UC-MSCs for treatment of various conditions.
Condition MSCPhase Clinical TrialStatusReferences
Intraventricular HemorrhageAllogeneic UC-MSC (intraventricular injection)Phase INCT02274428Completed[128]
Bronchopulmonary Dysplasia (BPD)Allogeneic UC-MSC (intratracheal injection)Phase INCT01632475Active, not re-cruiting[129]
Cerebral PalsyAllogeneic CB- and UC-MSCPhase I/IINCT03473301Completed-
Hypoxic-Ischemic EncephalopathyAllogeneic UC-MSCPilot phase INCT03635450Completed[130]
Bronchopulmonary dysplasia (BPD)UC-MSCPhase IINCT01828957Completed[131]
Myocardial InfarctionAllogeneic UC-MSCPhase INCT03798353Completed-
AutismUC-MSCPhase IINCT04089579Active, not recruiting-
Allogeneic UC-MSCPhase INCT03099239Completed[132]

3.2.3. Placenta-Derived MSCs (P-MSCs)

The placenta is a feto-maternal organ that is usually discarded post-partum, thus its easy availability and non-invasive harvesting. Recently, it has been shown that several parts of the placenta are rich and sustainable MSC sources unlike the bone marrow [133]. In comparison to BM-MSCs, P-MSCs showed a higher replicative capacity and broader differentiation abilities, which are related to the placental function of supporting fetus growth [134].
MSCs derived from the fetal tissues of the placenta have been used in animal disease models of several disorders such as cancer, liver diseases, cardiac disorders, ulcers, bone diseases, neurological diseases, and more recently, coronavirus (COVID-19). They are widely available and characterized by a high secretion of paracrine effects, a low immunogenicity, and low risk of senescence. However, the molecular mechanisms of their specific immunomodulatory properties are still not elucidated.

3.2.4. Amniotic Fluid-Derived MSCs (AF-MSCs)

The amniotic fluid is a rich source of fetal cells, including MSCs. It can be collected either invasively during pregnancy by amniocentesis from second trimester amniotic fluid, which might result in fetus infection, or during a C-section. These populations might, however, differ in terms of potency, maturity, and plasticity since they originate from two different pregnancy timepoints [135]. AF-MSCs harvested during C-section were characterized by Spitzhorn et al [135]. They were shown to meet the MSC criteria described by the ISCT. AF-MSCs were shown in various studies to express the pluripotency factor Oct4, but this could not be confirmed by Spitzhorn et al. [135,136,137]. Moreover, these findings remain controversial since the self-renewal function of Oct4 has not yet been defined in AF-MSCs, and the studies rather focus on the expression without addressing the function of Oct4 [135,138]. AF-MSCs were also shown to express the early embryonic glycolipid antigens SSEA4 and c-Kit, which are necessary for the maintenance and differentiation of the hematopoietic stem cells [135]. Analysis of AF-MSC-conditioned media revealed the presence of several pro- and anti-angiogenic factors, i.e., vascular endothelial growth factor (VEGF), interleukin 8 (IL-8), and IFNγ [139]. Moreover, Mirabella et al. showed that AF-MSCs do not directly contribute to bone formation but do contribute to the vascular modeling of the engineered bone [139]. The underlying mechanisms are still not elucidated.

4. Culture Conditions-Dependent Heterogeneity

In addition, donor variations and differences in the sources of isolation, MSC heterogeneity is also strongly dependent on their culture conditions. Hereby, several factors must be considered, including culture medium, O2 tension, mechanical stimuli, inflammatory stimuli, and mechanical cues [140].

4.1. Culture Medium

MSCs cultured in vitro can undergo morphological, phenotypical, and genetic changes with increasing passage numbers. This can be additionally modulated by the composition of the culture medium, which was shown to influence senescence levels and differentiation capacity [141]. Nowadays, several culture media and technologies are used for the expansion of MSCs, such as fetal bovine serum (FBS) or xeno-free or chemically defined media, to avoid FBS batch-to-batch differences.

4.2. O2 Tension

MSCs are generally cultured in vitro under normoxic conditions, despite the fact that biological niches such as the adipose or the bone marrow niches are adapted to hypoxic O2 tensions. Our group and several others showed O2 tension-dependent differences in the proliferative capacities, surface marker expression profiles, and differentiation capacities of different types of MSCs [142,143,144,145]. In addition to this, the hypoxic environment offers protection against replicative senescence and damaging factors [146]. It has also been reported that low oxygen levels can also facilitate the release of trophic factors and angiogenesis growth factors, thus contributing to the improvement of ischemic injuries [140,147,148].

5. Human Induced Pluripotent Stem Cell (iPSC)-Derived MSCs (iMSCs)

A robust expansion of therapeutic numbers of MSCs is frequently hard to achieve in an autologous setting due to higher senescence, DNA damage accumulation, genome instability, and oxidative stress. These factors challenge the manufacturing possibilities of homogenous and large numbers of MSC products, both for research and for the development of cell-based therapies. iPSCs derived from MSCs have been proposed as a clinically relevant alternative to bypass these limitations by suppressing the existing mechanical memory, which stores epigenetic and transcriptional information from the past environment that biases the cell fate [149]. Additionally, they are theoretically unlimited in supply and are more convenient for genetic modulation, scale-up production, and quality control. iPSCs with different tissue and reprogramming backgrounds could be differentiated into different types of somatic cells, including mesenchymal progenitors that have similar properties to somatic tissue-derived MSCs [150]. In the last decade, human iMSCs have been successfully used for improvement of bone regeneration in mice and mini-pigs [151,152,153], promotion of mucosal healing in mouse models of inflammatory bowel disease [154], and treatment of skin ischemia in mouse models [155].
A simple one-step protocol for the generation of MSCs from iPSCs exhibiting MSC characteristics, including expression of surface markers and trilineage differentiation potential, has been suggested by Zhou et al [156]. These results support the potential application for industrial-scale production of iMSCs. Zhou et al. showed that iMSCs were similar in their morphology, immune phenotype, in vitro differentiation potential, DNA methylation patterns, prevention of bone loss, and promotion of bone repair to BM-MSCs [73]. However, their tumorigenic capacity increased, although their proliferation rate was higher. Furthermore, their transplantation into rats with osteonecrosis of the femoral head effectively led to the promotion of bone repair and the prevention of bone loss. Eto et al. showed that MSCs derived from iPSCs could suppress cartilage degeneration and improve joint destruction in an osteoarthritis model [155]. Ozay et al. reported that administration of iMSCs in a humanized mouse model of GvHD led to reduced disease severity and prolonged survival [157]. The mechanisms of action are, however, not yet clearly elucidated. Bloor et al. conducted a Phase I trial using iPSC-derived MSCs (NCT02923375) in subjects with steroid-resistant acute GvHD to investigate their safety and tolerability [158]. They were shown to be safe and well tolerated by all patients, which is a great advantage for possible applications in diverse other inflammatory diseases.

6. Conclusions and Future Perspectives

This review summarizes two of the factors that mainly affect MSC heterogeneity, namely donor and tissue source, thus constituting a limiting factor inhibiting the exploitation of their full potential in therapeutical applications and industrialization. Growing evidence emerged in the last decade supporting the immunomodulatory features of MSCs, and various clinical trials with different experimental settings showed that administration of MSCs is in fact beneficial. For this, further research needs to be developed to establish new methods to eliminate or control this inherent heterogeneity and standardize MSC production for clinical applications. For clinical application, MSC potency needs to be determined and is defined by the therapeutical activity of a cell/cell population as indicated by appropriate laboratory tests or adequately developed and controlled clinical data. This potency is independent from the classical criteria of MSC to form bone, cartilage, and adipose tissue but is instead based on paracrine effects, cytokine release, surface and homing markers, as well as various other mechanisms as documented and granted by the US FDA for the treatment of neurological conditions in children. In contrast to paracrine mechanisms for neurological disorders, bone and cartilage formation requires a distinct cellular repertoire and signature for regeneration in vivo, as described by our group [51] and Hochmann et al. [52].

Author Contributions

M.O. writing—original draft preparation; writing—review and editing. G.K. supervision; writing—review and editing. All authors have read and agreed to the published version of the manuscript.

Funding

Funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation)—417677437/GRK2578.

Institutional Review Board Statement

The study was conducted in accordance with the Declaration of Helsinki, and approved by the Ethics Committee of the University Hospital Düsseldorf (4258/3484/3436).

Informed Consent Statement

Informed consent has been obtained from patients for blood donation.

Data Availability Statement

Not applicable.

Conflicts of Interest

The authors declare no conflict of interest.

References

  1. Friedenstein, A.J.; Chailakhjan, R.K.; Lalykina, K.S. The development of fibroblast colonies in monolayer cultures of guinea-pig bone marrow and spleen cells. Cell Prolif. 1970, 3, 393–403. [Google Scholar] [CrossRef]
  2. Caplan, A.I. Mesenchymal stem cells. J. Orthop. Res. 1991, 9, 641–650. [Google Scholar] [CrossRef] [PubMed]
  3. Owen, M. Marrow stromal stem cells. J. Cell Sci. Suppl. 1988, 10, 63–76. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  4. Horwitz, E.M.; Le Blanc, K.; Dominici, M.; Mueller, I.; Slaper-Cortenbach, I.; Marini, F.C.; Deans, R.J.; Krause, D.S.; Keating, A.; International Society for Cellular Therapy. Clarification of the nomenclature for MSC: The International Society for Cellular Therapy position statement. Cytotherapy 2005, 7, 393–395. [Google Scholar] [CrossRef] [PubMed]
  5. Bianco, P.; Cao, X.; Frenette, P.S.; Mao, J.J.; Robey, P.G.; Simmons, P.J.; Wang, C.-Y. The meaning, the sense and the significance: Translating the science of mesenchymal stem cells into medicine. Nat. Med. 2013, 19, 35–42. [Google Scholar] [CrossRef] [Green Version]
  6. Pittenger, M.F.; Mackay, A.M.; Beck, S.C.; Jaiswal, R.K.; Douglas, R.; Mosca, J.D.; Moorman, M.A.; Simonetti, D.W.; Craig, S.; Marshak, D.R. Multilineage Potential of Adult Human Mesenchymal Stem Cells. Science 1999, 284, 143–147. [Google Scholar] [CrossRef] [Green Version]
  7. Bianco, P. Bone and the hematopoietic niche: A tale of two stem cells. Blood 2011, 117, 5281–5288. [Google Scholar] [CrossRef] [Green Version]
  8. da Silva Meirelles, L.; Chagastelles, P.C.; Nardi, N.B. Mesenchymal stem cells reside in virtually all post-natal organs and tissues. J. Cell Sci. 2006, 119 Pt 11, 2204–2213. [Google Scholar] [CrossRef] [Green Version]
  9. Dominici, M.; Le Blanc, K.; Mueller, I.; Slaper-Cortenbach, I.; Marini, F.; Krause, D.; Deans, R.; Keating, A.; Prockop, D.; Horwitz, E. Minimal criteria for defining multipotent mesenchymal stromal cells. The International Society for Cellular Therapy position statement. Cytotherapy 2006, 8, 315–317. [Google Scholar] [CrossRef]
  10. Phinney, D.G.; Prockop, D.J. Concise Review: Mesenchymal Stem/Multipotent Stromal Cells: The State of Transdifferentiation and Modes of Tissue Repair—Current Views. Stem Cells 2007, 25, 2896–2902. [Google Scholar] [CrossRef]
  11. Le Blanc, K.; Rasmusson, I.; Sundberg, B.; Götherström, C.; Hassan, M.; Uzunel, M.; Ringdén, O. Treatment of severe acute graft-versus-host disease with third party haploidentical mesenchymal stem cells. Lancet 2004, 363, 1439–1441. [Google Scholar] [CrossRef]
  12. Bartholomew, A.; Sturgeon, C.; Siatskas, M.; Ferrer, K.; McIntosh, K.; Patil, S.; Hardy, W.; Devine, S.; Ucker, D.; Deans, R.; et al. Mesenchymal stem cells suppress lymphocyte proliferation in vitro and prolong skin graft survival in vivo. Exp. Hematol. 2002, 30, 42–48. [Google Scholar] [CrossRef] [PubMed]
  13. Di Nicola, M.; Carlo-Stella, C.; Magni, M.; Milanesi, M.; Longoni, P.D.; Matteucci, P.; Grisanti, S.; Gianni, A.M. Human bone marrow stromal cells suppress T-lymphocyte proliferation induced by cellular or nonspecific mitogenic stimuli. Blood 2002, 99, 3838–3843. [Google Scholar] [CrossRef]
  14. Jiang, X.-X.; Zhang, Y.; Liu, B.; Zhang, S.-X.; Wu, Y.; Yu, X.-D.; Mao, N. Human mesenchymal stem cells inhibit differentiation and function of monocyte-derived dendritic cells. Blood 2005, 105, 4120–4126. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  15. Nauta, A.J.; Kruisselbrink, A.B.; Lurvink, E.; Willemze, R.; Fibbe, W.E. Mesenchymal Stem Cells Inhibit Generation and Function of Both CD34+-Derived and Monocyte-Derived Dendritic Cells. J. Immunol. 2006, 177, 2080–2087. [Google Scholar] [CrossRef] [PubMed]
  16. Spaggiari, G.M.; Capobianco, A.; Becchetti, S.; Mingari, M.C.; Moretta, L. Mesenchymal stem cell-natural killer cell interactions: Evidence that activated NK cells are capable of killing MSCs, whereas MSCs can inhibit IL-2-induced NK-cell proliferation. Blood 2006, 107, 1484–1490. [Google Scholar] [CrossRef]
  17. Espagnolle, N.; Balguerie, A.; Arnaud, E.; Sensebé, L.; Varin, A. CD54-Mediated Interaction with Pro-inflammatory Macrophages Increases the Immunosuppressive Function of Human Mesenchymal Stromal Cells. Stem Cell Rep. 2017, 8, 961–976. [Google Scholar] [CrossRef] [Green Version]
  18. Franquesa, M.; Mensah, F.K.; Huizinga, R.; Strini, T.; Boon, L.; Lombardo, E.; DelaRosa, O.; Laman, J.D.; Grinyó, J.M.; Weimar, W.; et al. Human Adipose Tissue-Derived Mesenchymal Stem Cells Abrogate Plasmablast Formation and Induce Regulatory B Cells Independently of T Helper Cells. Stem Cells 2015, 33, 880–891. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  19. Asari, S.; Itakura, S.; Ferreri, K.; Liu, C.-P.; Kuroda, Y.; Kandeel, F.; Mullen, Y. Mesenchymal stem cells suppress B-cell terminal differentiation. Exp. Hematol. 2009, 37, 604–615. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  20. Healy, M.E.; Bergin, R.; Mahon, B.P.; English, K. Mesenchymal Stromal Cells Protect Against Caspase 3-Mediated Apoptosis of CD19+Peripheral B Cells Through Contact-Dependent Upregulation of VEGF. Stem Cells Dev. 2015, 24, 2391–2402. [Google Scholar] [CrossRef] [Green Version]
  21. Heldman, A.W.; DiFede, D.L.; Fishman, J.E.; Zambrano, J.P.; Trachtenberg, B.H.; Karantalis, V.; Mushtaq, M.; Williams, A.R.; Suncion, V.Y.; McNiece, I.K.; et al. Transendocardial Mesenchymal Stem Cells and Mononuclear Bone Marrow Cells for Ischemic Cardiomyopathy: The TAC-HFT Randomized Trial. JAMA 2014, 311, 62–73. [Google Scholar] [CrossRef] [PubMed]
  22. Fukumitsu, M.; Suzuki, K. Mesenchymal stem/stromal cell therapy for pulmonary arterial hypertension: Comprehensive review of preclinical studies. J. Cardiol. 2019, 74, 304–312. [Google Scholar] [CrossRef]
  23. Chen, S.-L.; Fang, W.-W.; Ye, F.; Liu, Y.-H.; Qian, J.; Shan, S.-J.; Zhang, J.-J.; Chunhua, R.Z.; Liao, L.-M.; Lin, S.; et al. Effect on left ventricular function of intracoronary transplantation of autologous bone marrow mesenchymal stem cell in patients with acute myocardial infarction. Am. J. Cardiol. 2004, 94, 92–95. [Google Scholar] [CrossRef] [PubMed]
  24. Garikipati, V.N.S.; Jadhav, S.; Pal, L.; Prakash, P.; Dikshit, M.; Nityanand, S. Mesenchymal Stem Cells from Fetal Heart Attenuate Myocardial Injury after Infarction: An In Vivo Serial Pinhole Gated SPECT-CT Study in Rats. PLoS ONE 2014, 9, e100982. [Google Scholar]
  25. Chiossone, L.; Conte, R.; Spaggiari, G.M.; Serra, M.; Romei, C.; Bellora, F.; Becchetti, F.; Andaloro, A.; Moretta, L.; Bottino, C. Mesenchymal Stromal Cells Induce Peculiar Alternatively Activated Macrophages Capable of Dampening Both Innate and Adaptive Immune Responses. Stem Cells 2016, 34, 1909–1921. [Google Scholar] [CrossRef] [Green Version]
  26. Dong, L.-H.; Jiang, Y.-Y.; Liu, Y.-J.; Cui, S.; Xia, C.-C.; Qu, C.; Jiang, X.; Qu, Y.-Q.; Chang, P.-Y.; Liu, F. The anti-fibrotic effects of mesenchymal stem cells on irradiated lungs via stimulating endogenous secretion of HGF and PGE2. Sci. Rep. 2015, 5, 8713. [Google Scholar] [CrossRef] [Green Version]
  27. Gomes, S.A.; Rangel, E.B.; Premer, C.; Dulce, R.A.; Cao, Y.; Florea, V.; Balkan, W.; Rodrigues, C.O.; Schally, A.V.; Hare, J.M. S-nitrosoglutathione reductase (GSNOR) enhances vasculogenesis by mesenchymal stem cells. Proc. Natl. Acad. Sci. USA 2013, 110, 2834–2839. [Google Scholar] [CrossRef]
  28. Phinney, D.G.; Kopen, G.; Righter, W.; Webster, S.; Tremain, N.; Prockop, D.J. Donor variation in the growth properties and osteogenic potential of human marrow stromal cells. J. Cell. Biochem. 1999, 75, 424–436. [Google Scholar] [CrossRef]
  29. Wagner, W.; Ho, A.D. Mesenchymal Stem Cell Preparations—Comparing Apples and Oranges. Stem Cell Rev. Rep. 2007, 3, 239–248. [Google Scholar] [CrossRef]
  30. Kanawa, M.; Igarashi, A.; Ronald, V.S.; Higashi, Y.; Kurihara, H.; Sugiyama, M.; Saskianti, T.; Pan, H.; Kato, Y. Age-dependent decrease in the chondrogenic potential of human bone marrow mesenchymal stromal cells expanded with fibroblast growth factor-2. Cytotherapy 2013, 15, 1062–1072. [Google Scholar] [CrossRef]
  31. Zaim, M.; Karaman, S.; Cetin, G.; Isik, S. Donor age and long-term culture affect differentiation and proliferation of human bone marrow mesenchymal stem cells. Ann. Hematol. 2012, 91, 1175–1186. [Google Scholar] [CrossRef] [PubMed]
  32. Siegel, G.; Kluba, T.; Hermanutz-Klein, U.; Bieback, K.; Northoff, H.; Schäfer, R. Phenotype, donor age and gender affect function of human bone marrow-derived mesenchymal stromal cells. BMC Med. 2013, 11, 146. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  33. Alves, H.; van Ginkel, J.; Groen, N.; Hulsman, M.; Mentink, A.; Reinders, M.; van Blitterswijk, C.; de Boer, J. A Mesenchymal Stromal Cell Gene Signature for Donor Age. PLoS ONE 2012, 7, e42908. [Google Scholar] [CrossRef]
  34. Mareschi, K.; Ferrero, I.; Rustichelli, D.; Aschero, S.; Gammaitoni, L.; Aglietta, M.; Madon, E.; Fagioli, F. Expansion of mesenchymal stem cells isolated from pediatric and adult donor bone marrow. J. Cell. Biochem. 2006, 97, 744–754. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  35. Psaroudis, R.T.; Singh, U.; Lora, M.; Jeon, P.; Boursiquot, A.; Stochaj, U.; Langlais, D.; Colmegna, I. CD26 is a senescence marker associated with reduced immunopotency of human adipose tissue-derived multipotent mesenchymal stromal cells. Stem Cell Res. Ther. 2022, 13, 358. [Google Scholar] [CrossRef]
  36. de Oliveira, G.L.V.; de Lima, K.W.A.; Colombini, A.M.; Pinheiro, D.G.; Panepucci, R.A.; Palma, P.V.B.; Brum, D.G.; Covas, D.T.; Simões, B.P.; de Oliveira, M.C.; et al. Bone marrow mesenchymal stromal cells isolated from multiple sclerosis patients have distinct gene expression profile and decreased suppressive function compared with healthy counterparts. Cell Transplant. 2015, 24, 151–165. [Google Scholar] [CrossRef] [Green Version]
  37. Ferrer, R.A.; Wobus, M.; List, C.; Wehner, R.; Schönefeldt, C.; Brocard, B.; Mohr, B.; Rauner, M.; Schmitz, M.; Stiehler, M.; et al. Mesenchymal stromal cells from patients with myelodyplastic syndrome display distinct functional alterations that are modulated by lenalidomide. Haematologica 2013, 98, 1677–1685. [Google Scholar] [CrossRef] [Green Version]
  38. Pachón-Peña, G.; Serena, C.; Ejarque, M.; Petriz, J.; Duran, X.; Oliva-Olivera, W.; Simó, R.; Tinahones, F.J.; Fernández-Veledo, S.; Vendrell, J. Obesity Determines the Immunophenotypic Profile and Functional Characteristics of Human Mesenchymal Stem Cells From Adipose Tissue. Stem Cells Transl. Med. 2016, 5, 464–475. [Google Scholar] [CrossRef]
  39. Wu, C.-L.; Diekman, B.O.; Jain, D.; Guilak, F. Diet-induced obesity alters the differentiation potential of stem cells isolated from bone marrow, adipose tissue and infrapatellar fat pad: The effects of free fatty acids. Int. J. Obes. 2012, 37, 1079–1087. [Google Scholar]
  40. Rodríguez, J.P.; Garat, S.; Gajardo, H.; Pino, A.M.; Seitz, G. Abnormal osteogenesis in osteoporotic patients is reflected by altered mesenchymal stem cells dynamics. J. Cell. Biochem. 1999, 75, 414–423. [Google Scholar] [CrossRef]
  41. Montecinos, L.; Reyes, P.; Rodríguez, J.P.; Ríos, S.; Martínez, J. Mesenchymal stem cells from osteoporotic patients produce a type I collagen-deficient extracellular matrix favoring adipogenic differentiation. J. Cell. Biochem. 2000, 79, 557–565. [Google Scholar]
  42. Selle, M.; Koch, J.D.; Ongsiek, A.; Ulbrich, L.; Ye, W.; Jiang, Z.; Krettek, C.; Neunaber, C.; Noack, S. Influence of age on stem cells depends on the sex of the bone marrow donor. J. Cell. Mol. Med. 2022, 26, 1594–1605. [Google Scholar] [CrossRef] [PubMed]
  43. Kannan, S.; Viswanathan, P.; Gupta, P.K.; Kolkundkar, U.K. Characteristics of Pooled Wharton’s Jelly Mesenchymal Stromal Cells (WJ-MSCs) and their Potential Role in Rheumatoid Arthritis Treatment. Stem Cell Rev. Rep. 2022, 18, 1851–1864. [Google Scholar] [CrossRef]
  44. Sammour, I.; Somashekar, S.; Huang, J.; Batlahally, S.; Breton, M.; Valasaki, K.; Khan, A.; Wu, S.; Young, K.C. The Effect of Gender on Mesenchymal Stem Cell (MSC) Efficacy in Neonatal Hyperoxia-Induced Lung Injury. PLoS ONE 2016, 11, e0164269. [Google Scholar] [CrossRef] [Green Version]
  45. Da Silva Meirelles, L.; Caplan, A.I.; Nardi, N.B. In Search of the In Vivo Identity of Mesenchymal Stem Cells. Stem Cells 2008, 26, 2287–2299. [Google Scholar] [CrossRef] [Green Version]
  46. Zhang, Z.-Y.; Teoh, S.-H.; Chong, M.S.; Schantz, J.T.; Fisk, N.M.; Choolani, M.A.; Chan, J. Superior Osteogenic Capacity for Bone Tissue Engineering of Fetal Compared with Perinatal and Adult Mesenchymal Stem Cells. Stem Cells 2009, 27, 126–137. [Google Scholar] [CrossRef]
  47. Anker, P.S.I.; Noort, W.A.; Scherjon, S.A.; Der Keur, C.K.-V.; Kruisselbrink, A.B.; Van Bezooijen, R.L.; Beekhuizen, W.; Willemze, R.; Kanhai, H.H.H.; E Fibbe, W. Mesenchymal stem cells in human second-trimester bone marrow, liver, lung, and spleen exhibit a similar immunophenotype but a heterogeneous multilineage differentiation potential. Haematologica 2003, 88, 845–852. [Google Scholar]
  48. Guillot, P.V.; De Bari, C.; Dell’Accio, F.; Kurata, H.; Polak, J.; Fisk, N.M. Comparative osteogenic transcription profiling of various fetal and adult mesenchymal stem cell sources. Differentiation 2008, 76, 946–957. [Google Scholar] [CrossRef] [PubMed]
  49. Heo, J.S.; Choi, Y.; Kim, H.-S.; Kim, H.O. Comparison of molecular profiles of human mesenchymal stem cells derived from bone marrow, umbilical cord blood, placenta and adipose tissue. Int. J. Mol. Med. 2015, 37, 115–125. [Google Scholar] [CrossRef] [Green Version]
  50. Noël, D.; Caton, D.; Roche, S.; Bony, C.; Lehmann, S.; Casteilla, L.; Jorgensen, C.; Cousin, B. Cell specific differences between human adipose-derived and mesenchymal–stromal cells despite similar differentiation potentials. Exp. Cell Res. 2008, 314, 1575–1584. [Google Scholar] [CrossRef]
  51. Sacchetti, B.; Funari, A.; Remoli, C.; Giannicola, G.; Kogler, G.; Liedtke, S.; Cossu, G.; Serafini, M.; Sampaolesi, M.; Tagliafico, E.; et al. No Identical “Mesenchymal Stem Cells” at Different Times and Sites: Human Committed Progenitors of Distinct Origin and Differentiation Potential Are Incorporated as Adventitial Cells in Microvessels. Stem Cell Rep. 2016, 6, 897–913. [Google Scholar] [CrossRef] [Green Version]
  52. Hochmann, S.; Ou, K.; Poupardin, R.; Mittermeir, M.; Textor, M.; Ali, S.; Wolf, M.; Ellinghaus, A.; Jacobi, D.; Elmiger, J.A.J.; et al. The enhancer landscape predetermines the skeletal regeneration capacity of stromal cells. Sci. Transl. Med. 2023, 15, eabm7477. [Google Scholar] [CrossRef] [PubMed]
  53. Bae, H.C.; Park, H.J.; Wang, S.Y.; Yang, H.R.; Lee, M.C.; Han, H.-S. Hypoxic condition enhances chondrogenesis in synovium-derived mesenchymal stem cells. Biomater. Res. 2018, 22, 28. [Google Scholar] [CrossRef] [Green Version]
  54. Zarychta-Wiśniewska, W.; Burdzińska, A.; Zielniok, K.; Koblowska, M.; Gala, K.; Pędzisz, P.; Nowicka, R.I.; Fogtman, A.; Aksamit, A.; Kulesza, A.; et al. The Influence of Cell Source and Donor Age on the Tenogenic Potential and Chemokine Secretion of Human Mesenchymal Stromal Cells. Stem Cells Int. 2019, 2019, 1613701. [Google Scholar] [CrossRef]
  55. Herrmann, M.; Hildebrand, M.; Menzel, U.; Fahy, N.; Alini, M.; Lang, S.; Benneker, L.; Verrier, S.; Stoddart, M.J.; Bara, J.J. Phenotypic Characterization of Bone Marrow Mononuclear Cells and Derived Stromal Cell Populations from Human Iliac Crest, Vertebral Body and Femoral Head. Int. J. Mol. Sci. 2019, 20, 3454. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  56. Li, X.; Bai, J.; Ji, X.; Li, R.; Xuan, Y.; Wang, Y. Comprehensive characterization of four different populations of human mesenchymal stem cells as regards their immune properties, proliferation and differentiation. Int. J. Mol. Med. 2014, 34, 695–704. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  57. Kern, S.; Eichler, H.; Stoeve, J.; Klüter, H.; Bieback, K. Comparative Analysis of Mesenchymal Stem Cells from Bone Marrow, Umbilical Cord Blood, or Adipose Tissue. Stem Cells 2006, 24, 1294–1301. [Google Scholar] [CrossRef]
  58. Almeida, A.; Lira, R.; Oliveira, M.; Martins, M.; Azevedo, Y.; Silva, K.R.; Carvalho, S.; Cortez, E.; Stumbo, A.C.; Carvalho, L.; et al. Bone marrow-derived mesenchymal stem cells transplantation ameliorates renal injury through anti-fibrotic and anti-inflammatory effects in chronic experimental renovascular disease. Biomed. J. 2021, 45, 629–641. [Google Scholar] [CrossRef]
  59. Li, C.Y.; Wu, X.-Y.; Tong, J.-B.; Yang, X.-X.; Zhao, J.-L.; Zheng, Q.-F.; Zhao, G.-B.; Ma, Z.-J. Comparative analysis of human mesenchymal stem cells from bone marrow and adipose tissue under xeno-free conditions for cell therapy. Stem Cell Res. Ther. 2015, 6, 55. [Google Scholar] [CrossRef] [Green Version]
  60. Bolli, R.; Hare, J.M.; Henry, T.D.; Lenneman, C.G.; March, K.L.; Miller, K.; Pepine, C.J.; Perin, E.C.; Traverse, J.H.; Willerson, J.T.; et al. Rationale and Design of the SENECA (StEm cell iNjECtion in cAncer survivors) Trial. Am. Heart J. 2018, 201, 54–62. [Google Scholar] [CrossRef]
  61. Gnecchi, M.; He, H.; Liang, O.D.; Melo, L.G.; Morello, F.; Mu, H.; Noiseux, N.; Zhang, L.; Pratt, R.E.; Ingwall, J.S.; et al. Paracrine action accounts for marked protection of ischemic heart by Akt-modified mesenchymal stem cells. Nat. Med. 2005, 11, 367–368. [Google Scholar] [CrossRef]
  62. Petrou, P.; Kassis, I.; Levin, N.; Paul, F.; Backner, Y.; Benoliel, T.; Oertel, F.C.; Scheel, M.; Hallimi, M.; Yaghmour, N.; et al. Beneficial effects of autologous mesenchymal stem cell transplantation in active progressive multiple sclerosis. Brain 2020, 143, 3574–3588. [Google Scholar] [CrossRef] [PubMed]
  63. Uccelli, A.; on behalf of the MESEMS study group; Laroni, A.; Brundin, L.; Clanet, M.; Fernandez, O.; Nabavi, S.M.; Muraro, P.A.; Oliveri, R.S.; Radue, E.W.; et al. MEsenchymal StEm cells for Multiple Sclerosis (MESEMS): A randomized, double blind, cross-over phase I/II clinical trial with autologous mesenchymal stem cells for the therapy of multiple sclerosis. Trials 2019, 20, 263. [Google Scholar] [CrossRef] [Green Version]
  64. Thebault, S.; Reaume, M.; Marrie, R.A.; Marriott, J.J.; Furlan, R.; Laroni, A.; A Booth, R.; Uccelli, A.; Freedman, M.S. High or increasing serum NfL is predictive of impending multiple sclerosis relapses. Mult. Scler. Relat. Disord. 2022, 59, 103535. [Google Scholar] [CrossRef] [PubMed]
  65. Kurtzberg, J.; Abdel-Azim, H.; Carpenter, P.; Chaudhury, S.; Horn, B.; Mahadeo, K.; Nemecek, E.; Neudorf, S.; Prasad, V.; Prockop, S.; et al. A Phase 3, Single-Arm, Prospective Study of Remestemcel-L, Ex Vivo Culture-Expanded Adult Human Mesenchymal Stromal Cells for the Treatment of Pediatric Patients Who Failed to Respond to Steroid Treatment for Acute Graft-versus-Host Disease. Biol. Blood Marrow Transplant. 2020, 26, 845–854. [Google Scholar] [CrossRef] [Green Version]
  66. Zuk, P.A.; Zhu, M.I.; Mizuno, H.; Huang, J.; Futrell, J.W.; Katz, A.J.; Benhaim, P.; Lorenz, H.P.; Hedrick, M.H. Multilineage Cells from Human Adipose Tissue: Implications for Cell-Based Therapies. Tissue Eng. 2001, 7, 211–228. [Google Scholar] [CrossRef] [Green Version]
  67. Kuhbier, J.W.; Weyand, B.; Radtke, C.; Vogt, P.M.; Kasper, C.; Reimers, K. Isolation, Characterization, Differentiation, and Application of Adipose-Derived Stem Cells. Adv. Biochem. Eng. Biotechnol. 2010, 123, 55–105. [Google Scholar]
  68. Bae, Y.K.; Kwon, J.H.; Kim, M.; Kim, G.-H.; Choi, S.J.; Oh, W.; Yang, Y.S.; Jin, H.J.; Jeon, H.B. Intracellular Calcium Determines the Adipogenic Differentiation Potential of Human Umbilical Cord Blood-Derived Mesenchymal Stem Cells via the Wnt5a/β-Catenin Signaling Pathway. Stem Cells Int. 2018, 2018, 6545071. [Google Scholar] [CrossRef] [Green Version]
  69. Fraser, J.K.; Wulur, I.; Alfonso, Z.; Hedrick, M.H. Adipose-Derived Stem Cells. In Mesenchymal Stem Cells: Methods and Protocols; Prockop, D.J., Bunnell, B.A., Phinney, D.G., Eds.; Humana Press: Totowa, NJ, USA, 2008; pp. 59–67. [Google Scholar]
  70. Choudhery, M.S.; Badowski, M.; Muise, A.; Pierce, J.; Harris, D.T. Donor age negatively impacts adipose tissue-derived mesenchymal stem cell expansion and differentiation. J. Transl. Med. 2014, 12, 8. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  71. Rehman, J.; Traktuev, D.; Li, J.; Merfeld-Clauss, S.; Temm-Grove, C.J.; Bovenkerk, J.E.; Pell, C.L.; Johnstone, B.H.; Considine, R.V.; March, K.L. Secretion of Angiogenic and Antiapoptotic Factors by Human Adipose Stromal Cells. Circulation 2004, 109, 1292–1298. [Google Scholar] [CrossRef]
  72. Ivanova-Todorova, E.; Bochev, I.; Mourdjeva, M.; Dimitrov, R.; Bukarev, D.; Kyurkchiev, S.; Tivchev, P.; Altunkova, I.; Kyurkchiev, D.S. Adipose tissue-derived mesenchymal stem cells are more potent suppressors of dendritic cells differentiation compared to bone marrow-derived mesenchymal stem cells. Immunol. Lett. 2009, 126, 37–42. [Google Scholar] [CrossRef]
  73. Zhou, M.; Xi, J.; Cheng, Y.; Sun, D.; Shu, P.; Chi, S.; Tian, S.; Ye, S. Reprogrammed mesenchymal stem cells derived from iPSCs promote bone repair in steroid-associated osteonecrosis of the femoral head. Stem Cell Res. Ther. 2021, 12, 175. [Google Scholar] [CrossRef] [PubMed]
  74. Kotze, P.G.; Spinelli, A.; Warusavitarne, J.; Di Candido, F.; Sahnan, K.; Adegbola, S.O.; Danese, S. Darvadstrocel for the treatment of patients with perianal fistulas in Crohn’s disease. Drugs Today 2019, 55, 95–105. [Google Scholar] [CrossRef] [PubMed]
  75. García-Olmo, D.; García-Arranz, M.; García, L.G.; Cuellar, E.S.; Blanco, I.F.; Prianes, L.A.; Montes, J.A.R.; Pinto, F.L.; Marcos, D.H.; García-Sancho, L. Autologous stem cell transplantation for treatment of rectovaginal fistula in perianal Crohn’s disease: A new cell-based therapy. Int. J. Colorectal Dis. 2003, 18, 451–454. [Google Scholar] [CrossRef]
  76. Lee, W.Y.; Park, K.J.; Cho, Y.B.; Yoon, S.N.; Song, K.H.; Kim, D.S.; Jung, S.H.; Kim, M.; Yoo, H.-W.; Kim, I. Autologous adipose tissue-derived stem cells treatment demonstrated favorable and sustainable therapeutic effect for Crohn’s fistula. Stem Cells 2013, 31, 2575–2581. [Google Scholar] [CrossRef] [PubMed]
  77. Garcia-Olmo, D.; Herreros, D.; Pascual, I.; Pascual, J.A.; Del-Valle, E.; Zorrilla, J.; De-La-Quintana, P.; Garcia-Arranz, M.; Pascual, M. Expanded adipose-derived stem cells for the treatment of complex perianal fistula: A phase II clinical trial. Dis. Colon. Rectum. 2009, 52, 79–86. [Google Scholar] [CrossRef]
  78. Panés, J.; García-Olmo, D.; Van Assche, G.; Colombel, J.F.; Reinisch, W.; Baumgart, D.C.; Dignass, A.; Nachury, M.; Ferrante, M.; Kazemi-Shirazi, L.; et al. Expanded allogeneic adipose-derived mesenchymal stem cells (Cx601) for complex perianal fistulas in Crohn’s disease: A phase 3 randomised, double-blind controlled trial. Lancet 2016, 388, 1281–1290. [Google Scholar] [CrossRef]
  79. Danisovic, L.; Oravcova, L.; Krajciova, L.; Novakova, Z.V.; Bohac, M.; Varga, I.; Vojtassak, J. Effect of long-term culture on the biological and morphological characteristics of human adipose tissue-derived stem Cells. J. Physiol. Pharmacol. 2017, 68, 149–158. [Google Scholar]
  80. Lotfy, A.; Salama, M.; Zahran, F.; Jones, E.; Badawy, A.; Sobh, M. Characterization of Mesenchymal Stem Cells Derived from Rat Bone Marrow and Adipose Tissue: A Comparative Study. Int. J. Stem Cells 2014, 7, 135–142. [Google Scholar] [CrossRef] [Green Version]
  81. Vidal, M.A.; Walker, N.J.; Napoli, E.; Borjesson, D.L.; Lange-Consiglio, A.; Romaldini, A.; Correani, A.; Corradetti, B.; Esposti, P.; Cannatà, M.F.; et al. Evaluation of Senescence in Mesenchymal Stem Cells Isolated from Equine Bone Marrow, Adipose Tissue, and Umbilical Cord Tissue. Stem Cells Dev. 2012, 21, 273–283. [Google Scholar] [CrossRef] [Green Version]
  82. Prianishnikov, V.A. On the concept of stem cell and a model of functional-morphological structure of the endometrium. Contraception 1978, 18, 213–223. [Google Scholar] [CrossRef] [PubMed]
  83. Wolff, E.F.; Wolff, A.B.; Du, H.; Taylor, H.S. Demonstration of Multipotent Stem Cells in the Adult Human Endometrium by In Vitro Chondrogenesis. Reprod. Sci. 2007, 14, 524–533. [Google Scholar] [CrossRef] [PubMed]
  84. Kazemnejad, S.; Zarnani, A.-H.; Khanmohammadi, M.; Mobini, S. Chondrogenic Differentiation of Menstrual Blood-Derived Stem Cells on Nanofibrous Scaffolds. Methods Mol. Biol. 2013, 1058, 149–169. [Google Scholar] [PubMed]
  85. Edwards, S.L.; Werkmeister, J.A.; Rosamilia, A.; Ramshaw, J.A.; White, J.F.; Gargett, C.E. Characterisation of clinical and newly fabricated meshes for pelvic organ prolapse repair. J. Mech. Behav. Biomed. Mater. 2013, 23, 53–61. [Google Scholar] [CrossRef]
  86. Zhou, C.; Yang, B.; Tian, Y.; Jiao, H.; Zheng, W.; Wang, J.; Guan, F. Immunomodulatory effect of human umbilical cord Wharton’s jelly-derived mesenchymal stem cells on lymphocytes. Cell. Immunol. 2011, 272, 33–38. [Google Scholar] [CrossRef] [Green Version]
  87. Xu, Y.; Hu, J.; Lv, Q.; Shi, C.; Qiu, M.; Xie, L.; Liu, W.; Yang, B.; Shan, W.; Cheng, Y.; et al. Endometrium-derived mesenchymal stem cells suppress progression of endometrial cancer via the DKK1-Wnt/β-catenin signaling pathway. Stem Cell Res. Ther. 2023, 14, 159. [Google Scholar] [CrossRef]
  88. Bozorgmehr, M.; Moazzeni, S.M.; Salehnia, M.; Sheikhian, A.; Nikoo, S.; Zarnani, A.-H. Menstrual blood-derived stromal stem cells inhibit optimal generation and maturation of human monocyte-derived dendritic cells. Immunol. Lett. 2014, 162 Pt B, 239–246. [Google Scholar] [CrossRef]
  89. De Bari, C.; Dell, F.; Tylzanowski, P.; Luyten, F.P. Multipotent mesenchymal stem cells from adult human synovial membrane. Arthritis. Rheum. 2001, 44, 1928–1942. [Google Scholar] [CrossRef]
  90. Fülber, J.; Maria, D.A.; da Silva, L.C.L.C.; Massoco, C.O.; Agreste, F.; Baccarin, R.Y.A. Comparative study of equine mesenchymal stem cells from healthy and injured synovial tissues: An in vitro assessment. Stem Cell Res. Ther. 2016, 7, 35. [Google Scholar] [CrossRef]
  91. Sekiya, I.; Katano, H.; Ozeki, N. Characteristics of MSCs in Synovial Fluid and Mode of Action of Intra-Articular Injections of Synovial MSCs in Knee Osteoarthritis. Int. J. Mol. Sci. 2021, 22, 2838. [Google Scholar] [CrossRef]
  92. Paradiso, F.; Lenna, S.; Isbell, R.; Garza, M.F.G.; Williams, M.; Varner, C.; Mcculloch, P.; Taraballi, F. Immunosuppressive potential evaluation of synovial fluid mesenchymal stem cells grown on 3D scaffolds as an alternative source of MSCs for osteoarthritis cartilage studies. Front. Biomater. Sci. 2022, 1, 989708. [Google Scholar] [CrossRef]
  93. Davatchi, F.; Abdollahi, B.S.; Mohyeddin, M.; Nikbin, B. Mesenchymal stem cell therapy for knee osteoarthritis: 5 years follow-up of three patients. Int. J. Rheum. Dis. 2015, 19, 219–225. [Google Scholar] [CrossRef] [PubMed]
  94. Orozco, L.; Munar, A.; Soler, R.; Alberca, M.; Soler, F.; Huguet, M.; Sentís, J.; Sánchez, A.; García-Sancho, J. Treatment of knee osteoarthritis with autologous mesenchymal stem cells: A pilot study. Transplantation 2013, 95, 1535–1541. [Google Scholar] [CrossRef] [PubMed]
  95. Davatchi, F.; Abdollahi, B.S.; Mohyeddin, M.; Shahram, F.; Nikbin, B. Mesenchymal stem cell therapy for knee osteoarthritis. Preliminary report of four patients. Int. J. Rheum. Dis. 2011, 14, 211–215. [Google Scholar] [CrossRef] [PubMed]
  96. Soler, R.; Orozco, L.; Munar, A.; Huguet, M.; López, R.; Vives, J.; Coll, R.; Codinach, M.; Garcia-Lopez, J. Final results of a phase I–II trial using ex vivo expanded autologous Mesenchymal Stromal Cells for the treatment of osteoarthritis of the knee confirming safety and suggesting cartilage regeneration. Knee 2016, 23, 647–654. [Google Scholar] [CrossRef]
  97. Arthur, A.; Rychkov, G.; Shi, S.; Koblar, S.A.; Gronthos, S. Adult Human Dental Pulp Stem Cells Differentiate Toward Functionally Active Neurons Under Appropriate Environmental Cues. Stem Cells 2008, 26, 1787–1795. [Google Scholar] [CrossRef] [Green Version]
  98. Pierdomenico, L.; Bonsi, L.; Calvitti, M.; Rondelli, D.; Arpinati, M.; Chirumbolo, G.; Becchetti, E.; Marchionni, C.; Alviano, F.; Fossati, V.; et al. Multipotent Mesenchymal Stem Cells with Immunosuppressive Activity Can Be Easily Isolated from Dental Pulp. Transplantation 2005, 80, 836–842. [Google Scholar] [CrossRef] [Green Version]
  99. Wada, N.; Menicanin, D.; Shi, S.; Bartold, P.M.; Gronthos, S. Immunomodulatory properties of human periodontal ligament stem cells. J. Cell. Physiol. 2009, 219, 667–676. [Google Scholar] [CrossRef]
  100. Huang, A.H.-C.; Snyder, B.R.; Cheng, P.-H.; Chan, A.W. Putative Dental Pulp-Derived Stem/Stromal Cells Promote Proliferation and Differentiation of Endogenous Neural Cells in the Hippocampus of Mice. Stem Cells 2008, 26, 2654–2663. [Google Scholar] [CrossRef] [Green Version]
  101. Kwack, K.H.; Lee, J.M.; Park, S.H.; Lee, H.W. Human Dental Pulp Stem Cells Suppress Alloantigen-induced Immunity by Stimulating T Cells to Release Transforming Growth Factor Beta. J. Endod. 2016, 43, 100–108. [Google Scholar] [CrossRef]
  102. Pisciotta, A.; Riccio, M.; Carnevale, G.; Lu, A.; De Biasi, S.; Gibellini, L.; La Sala, G.B.; Bruzzesi, G.; Ferrari, A.; Huard, J.; et al. Stem cells isolated from human dental pulp and amniotic fluid improve skeletal muscle histopathology in mdx/SCID mice. Stem Cell Res. Ther. 2015, 6, 156. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  103. Rubinstein, P.; Rosenfield, R.E.; Adamson, J.W.; Stevens, C.E. Stored placental blood for unrelated bone marrow reconstitution. Blood 1993, 81, 1679–1690. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  104. Mareschi, K.; Biasin, E.; Piacibello, W.; Aglietta, M.; Madon, E.; Fagioli, F. Isolation of human mesenchymal stem cells: Bone marrow versus umbilical cord blood. Haematologica 2001, 86, 1099–1100. [Google Scholar] [PubMed]
  105. Wexler, S.A.; Donaldson, C.; Denning-Kendall, P.; Rice, C.; Bradley, B.; Hows, J.M. Adult bone marrow is a rich source of human mesenchymal ‘stem’ cells but umbilical cord and mobilized adult blood are not. Br. J. Haematol. 2003, 121, 368–374. [Google Scholar] [CrossRef] [Green Version]
  106. Bieback, K.; Netsch, P. Isolation, Culture, and Characterization of Human Umbilical Cord Blood-Derived Mesenchymal Stromal Cells. Mesenchymal Stem Cells Methods Protoc. 2016, 1416, 245–258. [Google Scholar]
  107. Erices, A.; Conget, P.; Minguell, J.J. Mesenchymal progenitor cells in human umbilical cord blood. Br. J. Haematol. 2000, 109, 235–242. [Google Scholar] [CrossRef] [Green Version]
  108. Goodwin, H.; Bicknese, A.; Chien, S.-N.; Bogucki, B.; Oliver, D.; Quinn, C.; Wall, D. Multilineage differentiation activity by cells isolated from umbilical cord blood: Expression of bone, fat, and neural markers. Biol. Blood Marrow Transplant. 2001, 7, 581–588. [Google Scholar]
  109. Hass, R.; Kasper, C.; Böhm, S.; Jacobs, R. Different populations and sources of human mesenchymal stem cells (MSC): A comparison of adult and neonatal tissue-derived MSC. Cell Commun. Signal. 2011, 9, 12. [Google Scholar]
  110. Karagianni, M.; Brinkmann, I.; Kinzebach, S.; Grassl, M.; Weiss, C.; Bugert, P.; Bieback, K. A comparative analysis of the adipogenic potential in human mesenchymal stromal cells from cord blood and other sources. Cytotherapy 2013, 15, 76–88.e2. [Google Scholar] [CrossRef] [Green Version]
  111. da Silva, C.; Durandt, C.; Kallmeyer, K.; Ambele, M.A.; Pepper, M.S. The Role of Pref-1 during Adipogenic Differentiation: An Overview of Suggested Mechanisms. Int. J. Mol. Sci. 2020, 21, 4104. [Google Scholar]
  112. Liedtke, S.; Buchheiser, A.; Bosch, J.; Bosse, F.; Kruse, F.; Zhao, X.; Santourlidis, S.; Kögler, G. The HOX Code as a “biological fingerprint” to distinguish functionally distinct stem cell populations derived from cord blood. Stem Cell Res. 2010, 5, 40–50. [Google Scholar] [CrossRef] [Green Version]
  113. Liedtke, S.; Sacchetti, B.; Laitinen, A.; Donsante, S.; Klöckers, R.; Laitinen, S.; Riminucci, M.; Kogler, G. Low oxygen tension reveals distinct HOX codes in human cord blood-derived stromal cells associated with specific endochondral ossification capacities in vitro and in vivo. J. Tissue Eng. Regen. Med. 2017, 11, 2725–2736. [Google Scholar] [CrossRef] [PubMed]
  114. Krumlauf, R. Hox genes in vertebrate development. Cell 1994, 78, 191–201. [Google Scholar] [CrossRef] [PubMed]
  115. Duboule, D. The vertebrate limb: A model system to study theHox/hom gene network during development and evolution. Bioessays 1992, 14, 375–384. [Google Scholar]
  116. Ackema, K.B.; Charité, J.; Laitinen, A.; Lampinen, M.; Liedtke, S.; Kilpinen, L.; Kerkelä, E.; Sarkanen, J.-R.; Heinonen, T.; Kogler, G.; et al. Mesenchymal Stem Cells from Different Organs are Characterized by Distinct Topographic Hox Codes. Stem Cells Dev. 2008, 17, 979–992. [Google Scholar] [CrossRef] [PubMed]
  117. Kluth, S.M.; Buchheiser, A.; Houben, A.P.; Geyh, S.; Krenz, T.; Radke, T.F.; Wiek, C.; Hanenberg, H.; Reinecke, P.; Wernet, P.; et al. DLK-1 as a Marker to Distinguish Unrestricted Somatic Stem Cells and Mesenchymal Stromal Cells in Cord Blood. Stem Cells Dev. 2010, 19, 1471–1483. [Google Scholar] [CrossRef] [Green Version]
  118. Andreas Reinisch; Etchart, N.; Thomas, D.; Hofmann, N.A.; Fruehwirth, M.; Sinha, S.; Chan, C.K.; Senarath-Yapa, K.; Seo, E.-Y.; Wearda, T.; et al. Epigenetic and in vivo comparison of diverse MSC sources reveals an endochondral signature for human hematopoietic niche formation. Blood 2015, 125, 249–260. [Google Scholar]
  119. Amable, P.R.; Teixeira, M.V.T.; Carias, R.B.V.; Granjeiro, J.M.; Borojevic, R. Protein synthesis and secretion in human mesenchymal cells derived from bone marrow, adipose tissue and Wharton’s jelly. Stem Cell Res. Ther. 2014, 5, 53. [Google Scholar] [CrossRef] [Green Version]
  120. Majore, I.; Moretti, P.; Hass, R.; Kasper, C. Identification of subpopulations in mesenchymal stem cell-like cultures from human umbilical cord. Cell Commun. Signal. 2009, 7, 6. [Google Scholar] [CrossRef] [Green Version]
  121. Bosch, J.; Houben, A.P.; Radke, T.F.; Stapelkamp, D.; Bünemann, E.; Balan, P.; Buchheiser, A.; Liedtke, S.; Kögler, G. Distinct differentiation potential of “MSC” derived from cord blood and umbilical cord: Are cord-derived cells true mesenchymal stromal cells? Stem Cells Dev. 2012, 21, 1977–1988. [Google Scholar] [CrossRef]
  122. Li, F.; Zhang, K.; Liu, H.; Yang, T.; Xiao, D.-J.; Wang, Y.-S. The neuroprotective effect of mesenchymal stem cells is mediated through inhibition of apoptosis in hypoxic ischemic injury. World J. Pediatr. 2019, 16, 193–200. [Google Scholar] [CrossRef] [PubMed]
  123. Benny, M.; Courchia, B.; Shrager, S.; Sharma, M.; Chen, P.; Duara, J.; Valasaki, K.; Bellio, M.A.; Damianos, A.; Huang, J.; et al. Comparative Effects of Bone Marrow-derived Versus Umbilical Cord Tissue Mesenchymal Stem Cells in an Experimental Model of Bronchopulmonary Dysplasia. Stem Cells Transl. Med. 2022, 11, 189–199. [Google Scholar] [CrossRef] [PubMed]
  124. Min, H.; Xu, L.; Parrott, R.; Kurtzberg, J.; Filiano, A. Abstract 4 Umbilical Cord-Derived Mesenchymal Stromal Cells Suppress Neuroinflammation and Promote Remyelination in the Spinal Cord. Stem Cells Transl. Med. 2022, 11 (Suppl. S1), S6. [Google Scholar] [CrossRef]
  125. Petriv, T.; Tatarchuk, M.; Tsymbaliyk, Y.; Rybachuk, O.; Tsymbaliuk, Y.; Tsymbaliuk, V. Abstract 14 Umbilical Cord Mesenchymal Stromal/Stem Cells Application for Spasticity Treatment in Multiple Sclerosis. Stem Cells Transl. Med. 2022, 11 (Suppl. S1), S16. [Google Scholar] [CrossRef]
  126. Xu, L.; Saha, A.; Parrott, R.; O’neil, S.; Kurtzberg, J.; Filiano, A. Abstract 5 Human Umbilical Cord Blood-Derived Cell Therapy Product, DUOC-01, Promotes Remyelination by Driving the Differentiation of Oligodendrocyte Progenitor Cells. Stem Cells Transl. Med. 2022, 11 (Suppl. S1), S7. [Google Scholar] [CrossRef]
  127. Wehbe, T.; Saab, M.A.; Chahine, N.A.; Margossian, T. Mesenchymal stem cell therapy for refractory scleroderma: A report of 2 cases. Stem Cell Investig. 2016, 3, 48. [Google Scholar] [CrossRef] [Green Version]
  128. Ahn, S.Y.; Chang, Y.S.; Sung, S.I.; Park, W.S. Mesenchymal Stem Cells for Severe Intraventricular Hemorrhage in Preterm Infants: Phase I Dose-Escalation Clinical Trial. Stem Cells Transl. Med. 2018, 7, 847–856. [Google Scholar] [CrossRef] [Green Version]
  129. Ahn, S.Y.; Chang, Y.S.; Kim, J.H.; Sung, S.I.; Park, W.S. Two-Year Follow-Up Outcomes of Premature Infants Enrolled in the Phase I Trial of Mesenchymal Stem Cells Transplantation for Bronchopulmonary Dysplasia. J. Pediatr. 2017, 185, 49–54.e2. [Google Scholar] [CrossRef] [Green Version]
  130. Cotten, C.M.; Fisher, K.; Malcolm, W.; Gustafson, K.E.; Cheatham, L.; Marion, A.; Greenberg, R.; Kurtzberg, J. A Pilot Phase I Trial of Allogeneic Umbilical Cord Tissue-Derived Mesenchymal Stromal Cells in Neonates With Hypoxic-Ischemic Encephalopathy. Stem Cells Transl. Med. 2023, 12, 355–364. [Google Scholar] [CrossRef]
  131. Ahn, S.Y.; Chang, Y.S.; Lee, M.H.; Sung, S.I.; Lee, B.S.; Kim, K.S.; Kim, A.-R.; Park, W.S. Stem Cells for Bronchopulmonary Dysplasia in Preterm Infants: A Randomized Controlled Phase II Trial. Stem Cells Transl. Med. 2021, 10, 1129–1137. [Google Scholar] [CrossRef]
  132. Sun, J.M.; Dawson, G.; Franz, L.; Howard, J.; McLaughlin, C.; Kistler, B.; Waters-Pick, B.; Meadows, N.; Troy, J.; Kurtzberg, J. Infusion of human umbilical cord tissue mesenchymal stromal cells in children with autism spectrum disorder. Stem Cells Transl. Med. 2020, 9, 1137–1146. [Google Scholar] [CrossRef]
  133. Wu, M.; Zhang, R.; Zou, Q.; Chen, Y.; Zhou, M.; Li, X.; Ran, R.; Chen, Q. Comparison of the Biological Characteristics of Mesenchymal Stem Cells Derived from the Human Placenta and Umbilical Cord. Sci. Rep. 2018, 8, 5014. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  134. Campagnoli, C.; Roberts, I.A.G.; Kumar, S.; Bennett, P.R.; Bellantuono, I.; Fisk, N.M. Identification of mesenchymal stem/progenitor cells in human first-trimester fetal blood, liver, and bone marrow. Blood 2001, 98, 2396–2402. [Google Scholar] [CrossRef] [PubMed]
  135. Spitzhorn, L.-S.; Rahman, S.; Schwindt, L.; Ho, H.-T.; Wruck, W.; Bohndorf, M.; Wehrmeyer, S.; Ncube, A.; Beyer, I.; Hagenbeck, C.; et al. Isolation and Molecular Characterization of Amniotic Fluid-Derived Mesenchymal Stem Cells Obtained from Caesarean Sections. Stem Cells Int. 2017, 2017, 5932706. [Google Scholar] [CrossRef] [Green Version]
  136. You, Q.; Tong, X.; Guan, Y.; Zhang, D.; Huang, M.; Zhang, Y.; Zheng, J. The Biological Characteristics of Human Third Trimester Amniotic Fluid Stem Cells. J. Int. Med. Res. 2009, 37, 105–112. [Google Scholar] [CrossRef] [Green Version]
  137. Tsai, M.; Lee, J.; Chang, Y.; Hwang, S. Isolation of human multipotent mesenchymal stem cells from second-trimester amniotic fluid using a novel two-stage culture protocol. Hum. Reprod. 2004, 19, 1450–1456. [Google Scholar] [CrossRef] [PubMed]
  138. Babaie, Y.; Herwig, R.; Greber, B.; Brink, T.C.; Wruck, W.; Groth, D.; Lehrach, H.; Burdon, T.; Adjaye, J. Analysis of Oct4-Dependent Transcriptional Networks Regulating Self-Renewal and Pluripotency in Human Embryonic Stem Cells. Stem Cells 2006, 25, 500–510. [Google Scholar] [CrossRef] [Green Version]
  139. Mirabella, T.; Gentili, C.; Daga, A.; Cancedda, R. Amniotic fluid stem cells in a bone microenvironment: Driving host angiogenic response. Stem Cell Res. 2013, 11, 540–551. [Google Scholar]
  140. Costa, L.A.; Eiro, N.; Fraile, M.; Gonzalez, L.O.; Saá, J.; Garcia-Portabella, P.; Vega, B.; Schneider, J.; Vizoso, F.J. Functional heterogeneity of mesenchymal stem cells from natural niches to culture conditions: Implications for further clinical uses. Cell. Mol. Life Sci. 2021, 78, 447–467. [Google Scholar]
  141. Yang, Y.-H.K.; Ogando, C.R.; See, C.W.; Chang, T.-Y.; Barabino, G.A. Changes in phenotype and differentiation potential of human mesenchymal stem cells aging in vitro. Stem Cell Res. Ther. 2018, 9, 131. [Google Scholar] [CrossRef] [Green Version]
  142. Hung, S.-P.; Ho, J.H.; Shih, Y.-R.V.; Lo, T.; Lee, O.K. Hypoxia promotes proliferation and osteogenic differentiation potentials of human mesenchymal stem cells. J. Orthop. Res. 2011, 30, 260–266. [Google Scholar] [CrossRef]
  143. Choi, J.R.; Pingguan-Murphy, B.; Abas, W.A.B.W.; Azmi, M.A.N.; Omar, S.Z.; Chua, K.H.; Safwani, W.K.Z.W. Impact of low oxygen tension on stemness, proliferation and differentiation potential of human adipose-derived stem cells. Biochem. Biophys. Res. Commun. 2014, 448, 218–224. [Google Scholar] [CrossRef] [PubMed]
  144. Yamamoto, Y.; Fujita, M.; Tanaka, Y.; Kojima, I.; Kanatani, Y.; Ishihara, M.; Tachibana, S. Low Oxygen Tension Enhances Proliferation and Maintains Stemness of Adipose Tissue–Derived Stromal Cells. BioRes. Open Access 2013, 2, 199–205. [Google Scholar] [CrossRef] [PubMed]
  145. Werle, S.B.; Chagastelles, P.; Pranke, P.; Casagrande, L. The effects of hypoxia on in vitro culture of dental-derived stem cells. Arch. Oral Biol. 2016, 68, 13–20. [Google Scholar] [CrossRef] [PubMed]
  146. Choi, J.R.; Yong, K.W.; Safwani, W.K.Z.W. Effect of hypoxia on human adipose-derived mesenchymal stem cells and its potential clinical applications. Cell. Mol. Life Sci. 2017, 74, 2587–2600. [Google Scholar] [CrossRef]
  147. Gnecchi, M.; He, H.; Noiseux, N.; Liang, O.D.; Zhang, L.; Morello, F.; Mu, H.; Melo, L.G.; Pratt, R.E.; Ingwall, J.S.; et al. Evidence supporting paracrine hypothesis for Akt-modified mesenchymal stem cell-mediated cardiac protection and functional improvement. FASEB J. 2006, 20, 661–669. [Google Scholar] [CrossRef]
  148. Hu, X.; Yu, S.P.; Fraser, J.L.; Lu, Z.; Ogle, M.E.; Wang, J.-A.; Wei, L. Transplantation of hypoxia-preconditioned mesenchymal stem cells improves infarcted heart function via enhanced survival of implanted cells and angiogenesis. J. Thorac. Cardiovasc. Surg. 2008, 135, 799–808. [Google Scholar] [CrossRef] [Green Version]
  149. Frobel, J.; Hemeda, H.; Lenz, M.; Abagnale, G.; Joussen, S.; Denecke, B.; Šarić, T.; Zenke, M.; Wagner, W. Epigenetic Rejuvenation of Mesenchymal Stromal Cells Derived from Induced Pluripotent Stem Cells. Stem Cell Rep. 2014, 3, 414–422. [Google Scholar] [CrossRef] [Green Version]
  150. de Peppo, G.M.; IMarcos-Campos, Á.; Kahler, D.J.; Alsalman, D.; Shang, L.; Vunjak-Novakovic, G.; Marolt, D. Engineering bone tissue substitutes from human induced pluripotent stem cells. Proc. Natl. Acad. Sci. USA 2013, 110, 8680–8685. [Google Scholar] [CrossRef]
  151. Sheyn, D.; Ben-David, S.; Shapiro, G.; De Mel, S.; Bez, M.; Ornelas, L.; Sahabian, A.; Sareen, D.; Da, X.; Pelled, G.; et al. Human Induced Pluripotent Stem Cells Differentiate Into Functional Mesenchymal Stem Cells and Repair Bone Defects. Stem Cells Transl. Med. 2016, 5, 1447–1460. [Google Scholar] [CrossRef]
  152. Jungbluth, P.; Spitzhorn, L.-S.; Grassmann, J.; Tanner, S.; Latz, D.; Rahman, M.S.; Bohndorf, M.; Wruck, W.; Sager, M.; Grotheer, V.; et al. Human iPSC-derived iMSCs improve bone regeneration in mini-pigs. Bone Res. 2019, 7, 32. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  153. Kamiya, D.; Takenaka-Ninagawa, N.; Motoike, S.; Kajiya, M.; Akaboshi, T.; Zhao, C.; Shibata, M.; Senda, S.; Toyooka, Y.; Sakurai, H.; et al. Induction of functional xeno-free MSCs from human iPSCs via a neural crest cell lineage. NPJ Regen. Med. 2022, 7, 47. [Google Scholar] [CrossRef]
  154. Yang, H.; Feng, R.; Fu, Q.; Xu, S.; Hao, X.; Qiu, Y.; Feng, T.; Zeng, Z.; Chen, M.; Zhang, S. Human induced pluripotent stem cell-derived mesenchymal stem cells promote healing via TNF-α-stimulated gene-6 in inflammatory bowel disease models. Cell Death Dis. 2019, 10, 718. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  155. Eto, S.; Goto, M.; Soga, M.; Kaneko, Y.; Uehara, Y.; Mizuta, H.; Era, T. Mesenchymal stem cells derived from human iPS cells via mesoderm and neuroepithelium have different features and therapeutic potentials. PLoS ONE 2018, 13, e0200790. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  156. Zhou, Y.; Liao, J.; Fang, C.; Mo, C.; Zhou, G.; Luo, Y. One-step Derivation of Functional Mesenchymal Stem Cells from Human Pluripotent Stem Cells. Bio-Protoc. 2018, 8, e3080. [Google Scholar] [CrossRef] [Green Version]
  157. Ozay, E.I.; Vijayaraghavan, J.; Gonzalez-Perez, G.; Shanthalingam, S.; Sherman, H.L.; Garrigan, D.T., Jr.; Chandiran, K.; Torres, J.A.; Osborne, B.A.; Tew, G.N.; et al. Cymerus™ iPSC-MSCs significantly prolong survival in a pre-clinical, humanized mouse model of Graft-vs-host disease. Stem Cell Res. 2019, 35, 101401. [Google Scholar] [CrossRef]
  158. Bloor, A.J.C.; Patel, A.; Griffin, J.E.; Gilleece, M.H.; Radia, R.; Yeung, D.T.; Drier, D.; Larson, L.S.; Uenishi, G.I.; Hei, D.; et al. Production, safety and efficacy of iPSC-derived mesenchymal stromal cells in acute steroid-resistant graft versus host disease: A phase I, multicenter, open-label, dose-escalation study. Nat. Med. 2020, 26, 1720–1725. [Google Scholar]
Figure 1. In vitro differentiation of hBM-MSCs. (A,B) Safranin O staining of a hBM-MSC chondrogenic pellet at day 21 of in vitro differentiation; (C) In vitro osteogenic differentiation of hBM-MSCs; (D) Alizarin Red S staining of hBM-MSCs at day 14 of in vitro osteogenic differentiation; (E) In vitro adipogenic differentiation of human hBM-MSCs; (F) Oil Red O staining of hBM-MSCs at day 21 of in vitro adipogenic differentiation. hBM-MSCs: Human bone marrow-derived mesenchymal stromal cells.
Figure 1. In vitro differentiation of hBM-MSCs. (A,B) Safranin O staining of a hBM-MSC chondrogenic pellet at day 21 of in vitro differentiation; (C) In vitro osteogenic differentiation of hBM-MSCs; (D) Alizarin Red S staining of hBM-MSCs at day 14 of in vitro osteogenic differentiation; (E) In vitro adipogenic differentiation of human hBM-MSCs; (F) Oil Red O staining of hBM-MSCs at day 21 of in vitro adipogenic differentiation. hBM-MSCs: Human bone marrow-derived mesenchymal stromal cells.
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Table 1. Positive and negative markers of MSCs.
Table 1. Positive and negative markers of MSCs.
Positive MarkersPhysiological Function
CD44Hyaluronic receptor, surface adhesion, migration
CD73Lymphocyte-vascular adhesion protein 2 (Ecto-5’-nucleotidase)
CD90Cell adhesion, migration, apoptosis, fibrosis, T cell activation
CD105Activation and proliferation of endothelial cells
CD106Vascular cell adhesion molecule-1 (VCAM-1)
CD146Melanoma cell adhesion molecule (MCAM)
Negative MarkersPhysiological Function
CD11bIntegrin αM subunit, NK Cells, neutrophils, monocytes, macrophages
CD14Lipopolysaccharide receptor, macrophages, monocytes
CD19B cell lymphocytes
CD34Adhesion molecule, hematopoietic stem cell
CD45B cell lymphocyte receptor complex
CD79B cell lymphocyte and B cell neoplasms
HLA-DRMHC class II cell surface receptor
Table 2. List of the main sources for isolation of MSCs, the respective isolation technique, and culture conditions. Yellow: adult tissues. Red: fetal/perinatal tissues.
Table 2. List of the main sources for isolation of MSCs, the respective isolation technique, and culture conditions. Yellow: adult tissues. Red: fetal/perinatal tissues.
MSC Source Isolation Technique
Bone marrowDensity gradient centrifugation, Ficoll gradient or red blood cell lysis of bone marrow aspirate
Adipose tissue Enzymatic or non-enzymatic digestion after liposuction or lipectomy
EndometriumEnzymatic digestion after scraping the myometrium of hysterectomy samples
Synovial membraneEnzymatic digestion of synovium harvested from the inner joint side
Dental tissueExtirpation of dental pulps after decoronation
Cord bloodDirect expansion
Umbilical cordEnzymatic digestion or direct expansion of umbilical cord tissue
Wharton’s jellyVein removal, scraping and enzymatic digestion
PlacentaEnzymatic digestion
Amniotic fluidAmniotic membrane perforation and tubing for fluid collection followed by density gradient centrifugation
Table 3. Examples of clinical trials of BM-MSCs for treatment of various conditions.
Table 3. Examples of clinical trials of BM-MSCs for treatment of various conditions.
Condition MSCPhase Clinical TrialStatusReferences
Multiple SclerosisAutologous BM-MSCPhase II NCT02166021Completed[62]
Autologous BM-MSCPhase II NCT02239393Completed[63,64]
Post-traumatic Pulp NecrosisAllogeneic BM-MSCPhase II/IIINCT04545307Completed-
Anthracycline-induced cardiomyopathy Allogeneic BM-MSCPhase I NCT02509156Completed[60]
SR-aGvHDBM-MSCPhase IIINCT02336230Completed[65]
Liver CirrhosisAutologous BM-MSCPhase IIINCT05080465Completed-
Covid-19 InfectionAllogeneic BM-MSCPhase INCT04397796Active, not recruiting-
Chronic Myocardial IschemiaAutologous BM-MSCPhase II NCT02462330Completed-
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Ouzin, M.; Kogler, G. Mesenchymal Stromal Cells: Heterogeneity and Therapeutical Applications. Cells 2023, 12, 2039. https://doi.org/10.3390/cells12162039

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Ouzin M, Kogler G. Mesenchymal Stromal Cells: Heterogeneity and Therapeutical Applications. Cells. 2023; 12(16):2039. https://doi.org/10.3390/cells12162039

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Ouzin, Meryem, and Gesine Kogler. 2023. "Mesenchymal Stromal Cells: Heterogeneity and Therapeutical Applications" Cells 12, no. 16: 2039. https://doi.org/10.3390/cells12162039

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