Search Results (247)

Background: Diabetic foot ulcers (DFUs) are a serious complication of diabetes and are often difficult to treat. Hyperbaric oxygen therapy (HBOT) has been proposed as an adjunctive treatment to promote healing, but its long-term clinical and biological effects remain insufficiently characterized. This study aimed to evaluate the impact of HBOT on systemic biomarkers, local microvasculature, and clinical outcomes in patients with DFUs. Methods: In this non-randomized prospective study, 20 patients with ischemic DFUs were followed over a 36-month period. Fourteen received HBOT in addition to standard care, while six received standard care alone. Clinical outcomes—including DFU resolution, recurrence, lower extremity amputation (LEA), and mortality—were assessed alongside systemic inflammatory and angiogenic biomarkers and wound characteristics at baseline and at 3, 6, 12, and 36 months. CD31 immunostaining was performed on available tissue samples. Results: The two groups were comparable at baseline (mean age 62 ± 12 years; diabetes duration 18 ± 9 years). At 3 months, the HBOT group showed significant reductions in erythrocyte sedimentation rate and DFU size (p < 0.05), with downward trends observed in C-reactive protein (CRP), vascular endothelial growth factor (VEGF), and placental growth factor (PlGF), and an increase in stromal-derived factor-1 alpha (SDF1-α). No significant changes were observed in the control group. CD31+ microvessel density appeared to increase in HBOT-treated DFU tissue after one month, although the sample size was limited. Patients receiving HBOT had lower rates of LEA and mortality, improved wound healing, and sustained outcomes over three years. DFU recurrence rates were similar between groups. Conclusions: HBOT was associated with improved wound healing and favorable biomarker profiles in patients with treatment-resistant ischemic DFUs. While these findings are encouraging, the small sample size and non-randomized design limit their generalizability, highlighting the need for larger, controlled studies. Full article

Titanium–aluminum–vanadium (Ti6Al4V) is a material chosen for spine, orthopedic, and dental implants due to its combination of desirable mechanical and biological properties. Lasers have been used to modify metal surfaces, enabling the generation of a surface on Ti6Al4V with distinct micro- and nano-scale structures. Studies indicate that topography with micro/nano features of osteoclast resorption pits causes bone marrow stromal cells (MSCs) and osteoprogenitor cells to favor differentiation into an osteoblastic phenotype. This study examined whether the biological response of human MSCs to Ti6Al4V surfaces is sensitive to laser treatment-controlled micro/nano-topography. First, 15 mm diameter Ti6Al4V discs (Spine Wave Inc., Shelton, CT, USA) were either machined (M) or additively manufactured (AM). Surface treatments included no laser treatment (NT), nanosecond laser (Ns), femtosecond laser (Fs), or nanosecond followed by femtosecond laser (Ns+Fs). Surface wettability, roughness, and surface chemistry were determined using sessile drop contact angle, laser confocal microscopy, X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM). Human MSCs were cultured in growth media on tissue culture polystyrene (TCPS) or test surfaces. On day 7, the levels of osteocalcin (OCN), osteopontin (OPN), osteoprotegerin (OPG), and vascular endothelial growth factor 165 (VEGF) in the conditioned media were measured. M NT, Fs, and Ns+Fs surfaces were hydrophilic; Ns was hydrophobic. AM NT and Fs surfaces were hydrophilic; AM Ns and Ns+Fs were hydrophobic. Roughness (Sa and Sz) increased after Ns and Ns+Fs treatment for both M and AM disks. All surfaces primarily consisted of oxygen, titanium, and carbon; Fs had increased levels of aluminum for both M and AM. SEM images showed that M NT discs had a smooth surface, whereas AM surfaces appeared rough at a higher magnification. Fs surfaces had a similar morphology to their respective NT disc at low magnification, but higher magnification revealed nano-scale bumps not seen on NT surfaces. AM Fs surfaces also had regular interval ridges that were not seen on non-femto laser-ablated surfaces. Surface roughness was increased on M and AM Ns and Ns+Fs disks compared to NT and Fs disks. OCN was enhanced, and DNA was reduced on Ns and Ns+Fs, with no difference between them. OPN, OPG, and VEGF levels for laser-treated M surfaces were unchanged compared to NT, apart from an increase in OPG on Fs. MSCs grown on AM Ns and Ns+Fs surfaces had increased levels of OCN per DNA. These results indicate that MSCs cultured on AM Ns and AM Ns+Fs surfaces, which exhibited unique roughness at the microscale and nanoscale, had enhanced differentiation to an osteoblastic phenotype. The laser treatments of the surface mediated this enhancement of MSC differentiation and warrant further clinical investigation. Full article

Cardiac tissue engineering is a promising strategy to restore cardiac function in heart failure patients. Understanding the cardiac tissue architecture including the cardiac stroma is essential for developing not only advanced cardiac tissue engineering but also novel therapeutic strategies. One of the crucial components of the cardiac stroma is the myocardial vasculature. To enhance the spatial visualization of the cardiac stromal cytoarchitecture with a particular focus on myocardial vasculature, we performed 3D reconstructions of the murine cardiac micro vessels using Serial Block-Face Scanning Electron Microscopy (SBF-SEM). These analyses revealed that pericyte cell bodies were primarily oriented lengthwise and extended several cellular protrusions towards the endothelium. At capillary branching points, some pericytes made contact with both capillaries emerging from branching. In addition to pericytes that are completely encapsulated by the common basal lamina together with capillary endothelial cells, we identified other vascular-associated cells located outside this sheath. Based on marker expression, these cells were distinguished from fibroblasts and suggested to be telocytes. The vascular-associated cells formed electron-dense contact zones with endothelial cells, suggesting functional coupling between these both cell types. In conclusion, this study provides detailed three-dimensional visualizations of the cardiac stroma with a particular focus on cardiac microvasculature, offering enhanced insight into the cardiac stromal cytoarchitecture. Full article

Micro-fragmented adipose tissue (MFAT) is a promising autologous therapy for knee osteoarthritis. To avoid repeated liposuction procedures for its clinical application, MFAT obtained from patients with knee osteoarthritis was stored at −80 °C in a tissue bank. This study describes the preparation, cryopreservation, thawing, and washing, as well as comprehensive analysis of cell populations in fresh and MFAT thawed after two years. Immunophenotyping of both fresh and thawed MFAT showed a significant presence of endothelial progenitors and pericytes in the stromal vascular fraction. Viability before (59.75%) and after freezing (55.73%) showed no significant difference. However, the average cell count per gram of MFAT was significantly reduced in thawed samples (3.00 × 10⁵) compared to fresh ones (5.64 × 10⁵), likely due to processing steps. Thawed MFAT samples showed increased CD73 expression on the CD31^highCD34^high subset of EP and SA-ASC, as well as increased expression of CD105 on EP, the CD31^lowCD34^low subset of EP, pericytes, and SA-ASC. Microbiological testing confirmed 100% sterility, and double washing efficiently removed DMSO, confirming sample safety. Histological analysis revealed healthy, uniformly shaped adipocytes with intact membranes. This approach allows accurate estimation of cell yield for intra-articular injection, ensuring delivery of the target cell number into the knee. Quality control analysis confirms that cryopreserved MFAT retains high cellular and structural integrity, supporting its safety and suitability for clinical application. Full article

Current treatment strategies for partial tendon tears often lack the capacity to promote true tissue regeneration and improve long-term clinical outcomes. This study tested the hypothesis that treatment of a partial defect in the rabbit common calcaneus tendon (CCT) with uncultured, unmodified, autologous, adipose-derived regenerative cells (UA-ADRCs) enables regenerative healing without scar formation. A full-thickness, 3 mm defect was produced in the midsubstance of the right gastrocnemius tendon, a component of the CCT, in adult female New Zealand white rabbits. Animals received either an injection of 28.3 × 10⁶ UA-ADRCs in 0.5 mL Ringer’s lactated solution (RLS) or saline, or RLS or saline alone as sham treatment. Tendons were analyzed 4 or 12 weeks post-treatment using histology, immunohistochemistry and non-destructive biomechanical testing. UA-ADRC-treated tendons showed newly formed connective tissue consistent with tendon regeneration, whereas sham-treated tendons developed scar tissue. Biomechanical testing showed significantly higher percent relaxation in UA-ADRC-treated tendons compared to sham controls (p < 0.05), indicating greater viscoelasticity characteristic of healthy or well-integrated tissue. Together, these findings suggest that UA-ADRC therapy may provide a regenerative, structure-modifying treatment for partial tendon tears. Full article

Tissue-engineered artificial skin has the potential to enhance wound healing without necessitating extensive surgical procedures or causing donor-site morbidity. The purpose of this study was to examine the possibility of developing tri-layered tissue-engineered full-thickness artificial skin with a basement membrane for clinical use to accelerate wound healing. We engineered full-thickness artificial skin with a basement membrane for wound healing by employing stromal vascular fraction (SVF) cells for the dermal layer and autologous keratinocytes for the epidermal layer. The fabrication of a basement membrane involved the use of 100% bovine collagen and 4% elastin produced through a low-temperature three-dimensional printer. Scaffolds for cells were printed with 100% bovine collagen. The basement membrane underwent evaluations for collagenase degradation, tensile strength, and structural characteristics using scanning electron microscopy. The final tri-layered full-thickness artificial skin included two cell scaffolds with a basement membrane between them. The basement membrane may support cellular attachment without inducing significant cytotoxic effects. This study presents a novel strategy for full-thickness artificial skin development, combining SVF and keratinocytes with an optimized collagen-elastin basement membrane. This method may overcome the significant limitations of current artificial skin, thereby contributing to the advancement of tissue-engineering in wound healing for clinical use. Full article

Background: The traditional management of acute burn wounds using eschar debridement followed by split-thickness skin grafting has notable drawbacks. Stromal vascular fraction (SVF), derived from autologous adipose tissue, promotes epithelialization and angiogenesis, while platelet-rich fibrin (PRF), obtained via centrifugation of patient blood, enhances wound healing. This study retrospectively analyzes the outcomes of patients with thermal injuries treated with a combination of topical SVF and PRF at the University Hospital Zurich Burn Center. Methods: From 2018 to 2020, 13 patients with deep partial-thickness burns (DPTBs) or mixed-pattern burns (MPBs) received combined topical SVF and PRF treatment. Eschar removal was performed enzymatically or surgically following hydrotherapy. SVF was collected via liposuction, and PRF from centrifuged blood. Healing progress, additional surgeries, and scar outcomes (assessed by the Manchester Scar Scale, MSS) were evaluated retrospectively. Results: The mean total body surface area burned was 29.6%, with 6.3% treated using SVF and PRF. Five patients required further surgical intervention for residual defects. Complete healing occurred within 20 days in patients without residual defects and within 51 days in those with defects. Higher MSS scores were observed in patients requiring additional surgery. No adverse effects were noted. Conclusions: Topical SVF and PRF offer a potentially less-invasive treatment for MPB and DPTB. However, due to frequent residual defects and regulatory concerns around SVF use, this approach cannot yet be considered a standard treatment. Full article

Plantar fasciitis is a common condition characterized by inflammation and degeneration of the plantar fascia, leading to heel pain and reduced mobility. Affecting both athletic and non-athletic populations, it is a leading cause of foot-related medical visits. Conservative treatments, including rest, physical therapy, and corticosteroid injections, provide relief for most patients, but a subset experiences persistent symptoms requiring advanced therapies. Emerging biologic treatments, such as platelet-rich plasma (PRP) and mesenchymal stem/stromal cell (MSC) therapy, have demonstrated potential in promoting tissue regeneration and reducing inflammation. Recently, MSC-derived extracellular vesicles (MSC-EVs) have gained attention for their regenerative properties, offering a promising, cell-free therapeutic approach. EVs mediate tissue repair through immunomodulation, anti-inflammatory signaling, and extracellular matrix stabilization. Preclinical studies suggest that EV therapy may improve tendon and ligament healing by promoting M2 macrophage polarization, inhibiting excessive metalloproteinase activity, and enhancing vascular remodeling. This review explores the potential of MSC-EVs as an innovative, non-surgical treatment for plantar fasciitis, addressing their mechanisms of action and current evidence in musculoskeletal regeneration. Full article

Cartilage and bone defects as well as osteoarthritis are prevalent worldwide, affecting individuals across all age groups, from young, active populations to older adults. The standard protocol in cartilage regeneration involves knee replacement surgery through the implantation of an endoprosthesis. Current clinical protocols involving cell-based therapies are associated with limitations, including the lack of functional cartilage-like tissue and dedifferentiation of chondrocyte, particularly during monoculture. Similarly, in bone regeneration, the “gold standard” is the use of bone auto- or allografts, which are associated with immunological rejection, inadequate vascularization, and limited osteogenesis. To overcome these limitations, various co-culture techniques have been introduced as promising strategies for cartilage and bone tissue regeneration. These systems aim to mimic native microenvironments by promoting interactions between chondrocytes and mesenchymal stromal cells (MSCs) in cartilage repair and between osteogenic and angiogenic cells in bone regeneration. This paper introduces different co-culture systems focusing on in vitro crosstalk between MSCs derived from various sources and other somatic cell populations in cartilage and bone regeneration. Full article

Background: Histological and immunohistochemical analyses of adipose tissue are essential for evaluating the quality and functionality of lipoaspirates in regenerative medicine and fat grafting procedures. These methods provide insights into tissue viability, cellular subtypes, and extracellular matrix (ECM) composition—all factors influencing graft retention and clinical outcomes. Purpose: This scoping review aims to summarize the most commonly used staining methods and their applications in the histology and immunohistochemistry of adipose tissue. By exploring qualitative and quantitative markers, we seek to guide researchers in selecting the appropriate methodologies for addressing experimental and translational research. Methods: A systematic search was conducted using PubMed, Ovid, and the Cochrane Library databases from inception to 2024, employing Boolean operators (“lipoaspirate” OR “fat graft” OR “gauze rolling” OR “decantation” OR “coleman fat” OR “celt” OR “nanofat” OR “lipofilling” OR “human fat” AND “histol*”). Studies were included if they utilized histology or immunohistochemistry on undigested human adipose tissue or its derivatives. The inclusion criteria focused on peer-reviewed, English-language studies reporting quantitative and qualitative data on adipose tissue markers. Results: Out of 166 studies analyzed, hematoxylin–eosin (H&E) was the most frequently employed histological stain (152 studies), followed by Masson Trichrome and Sudan III. Immunohistochemical markers such as CD31, CD34, and perilipin were extensively used to distinguish stromal vascular fraction (SVF) cells, adipocytes, and inflammatory processes. Studies employing semiquantitative scoring demonstrated enhanced comparability, particularly for fibrosis, necrosis, and oil cyst evaluation. Quantitative analyses focused on SVF cell density, mature adipocyte integrity, and ECM composition. Methodological inconsistencies, particularly in preparation protocols, were observed in 25 studies. Conclusions: This review highlights the critical role of histological and immunohistochemical methods in adipose tissue research. H&E staining remains the cornerstone for general tissue evaluation in the clinical context, while specialized stains and immunohistochemical markers allow for detailed analyses of specific cellular and ECM components in experimental research. Standardizing preparation and evaluation protocols will enhance interstudy comparability and support advancements in adipose tissue-based therapies. Full article

Obesity is a growing global health concern, contributing to diseases such as cancer, autoimmune disorders, and neurodegenerative conditions. Adipose tissue dysfunction, characterized by abnormal adipokine secretion and chronic inflammation, plays a key role in these conditions. Adipose-derived extracellular vesicles (ADEVs) have emerged as critical mediators in obesity-related diseases. However, the study of mature adipocyte-derived EVs (mAdipo-EVs) is limited due to the short lifespan of mature adipocytes in culture, low EV yields, and the low abundance of these EV subpopulations in the circulation. Additionally, most studies rely on rodent models, which have differences in adipose tissue biology compared to humans. To overcome these challenges, we developed a standardized approach for differentiating human preadipocytes (preAdipos) into mature differentiated adipocytes (difAdipos), which produce high-yield, human adipocyte EVs (Adipo-EVs). Using visceral adipose tissue from bariatric surgical patients, we isolated the stromal vascular fraction (SVF) and differentiated preAdipos into difAdipos. Brightfield microscopy revealed that difAdipos exhibited morphological characteristics comparable to mature adipocytes (mAdipos) directly isolated from visceral adipose tissue, confirming their structural similarity. Additionally, qPCR analysis demonstrated decreased preadipocyte markers and increased mature adipocyte markers, further validating successful differentiation. Functionally, difAdipos exhibited lipolytic activity comparable to mAdipos, supporting their functional resemblance to native adipocytes. We then isolated preAdipo-EVs and difAdipo-EVs using tangential flow filtration and characterized them using bulk and single EV analysis. DifAdipo-EVs displayed classical EV and adipocyte-specific markers, with significant differences in biomarker expression compared to preAdipo-EVs. These findings demonstrate that difAdipos serve as a reliable surrogate for mature adipocytes, offering a consistent and scalable source of adipocyte-derived EVs for studying obesity and its associated disorders. Full article

Papillary thyroid cancer (PTC) contains mesenchymal stem/stromal cells (MSCs), but their contribution to PTC progression is not clear. In this study, we compared the transcriptional signatures of normal thyroid (NT) and PTC-derived MSCs with the aim of determining if these have distinct transcriptomes that might influence PTC progression. We used flow cytometry in combination with a panel of MSC clusters of differentiation (CD) markers and showed that both thyroid MSC populations expressed MSC markers and lacked expression of markers not normally expressed by MSCs. In addition, we determined that both MSC populations could differentiate to adipocytes and osteocytes. Analysis of single cell RNA sequencing data from both MSC populations revealed, regardless of tissue of origin, that both contained similar numbers of subpopulations. Cluster analysis revealed similarity in expression of both MSC populations for stromal markers, the vascular marker VEGFA and the smooth muscle marker CALD1, while smaller subpopulations expressed markers of more lineage-committed thyroid cells. PTC MSCs also showed upregulated expression of 28 genes, many of which are known to be involved in epithelial–mesenchymal transition (EMT) and/or disease progression in several types of cancers, including but not limited to breast cancer, gastric cancer, cervical carcinoma, bladder cancer and thyroid cancer. This included several members of the S100 and IGFBP gene families. Taken together, these data support a role for PTC MSCs in PTC progression. Full article

Background: Von Hippel-Lindau (VHL) disease, a hereditary cancer syndrome, is characterized by mutations in the VHL gene, which result in the stabilization of hypoxia-inducible factors (HIF)-1α and -2α, ultimately leading to the development of highly vascularized tumors, such as hemangioblastomas of the central nervous system (CNS-HBs). The standard treatment for these brain tumors is neurosurgical resection. However, multiple surgeries are often necessary due to tumor recurrence, which increases the risk of neurological sequelae. Thus, elucidation of the proliferative behavior of hemangioblastomas (with the aim of identifying biomarkers associated with tumor progression) and the development of pharmacological therapies could reduce the need for repeated surgical interventions and provide alternative treatment options for unresectable CNS-HBs. Belzutifan (Welireg™), a selective HIF-2α inhibitor and the only FDA-approved non-surgical option, has shown limited efficacy in CNS-HBs, highlighting the need for alternative therapeutic strategies. Results: In this study, primary cell cultures were successfully established from CNS-HB tissue samples of VHL patients, achieving a 75% success rate. These cultures were predominantly composed of stromal cells and pericytes. The proliferative patterns of patient-derived HB cell cultures significantly correlated with tumor burden and recurrence in VHL patients. Furthermore, flow cytometry, reverse transcription-PCR, and Western blot analyses revealed marked overexpression of both HIF-1α and HIF-2α isoforms in primary HB cells. In addition, evaluation of the therapeutic potential of acriflavine, a dual HIF-1α/HIF-2α inhibitor, demonstrated reduced HB cells viability, induced G2/M cell cycle arrest, and predominantly triggered necrotic cell death in patient-derived HB cultures. Conclusions: These results suggest that the in vitro proliferative dynamics of HB cell cultures may reflect clinical characteristics associated with CNS-HB progression, potentially serving as indicators to predict tumor development in patients with VHL. Furthermore, our findings support the simultaneous targeting of both HIF-1α and HIF-2α isoforms as a promising non-invasive therapeutic strategy. Full article

Background: Adipose tissue growth follows a biphasic process involving both cellular hyperplasia (an increase in adipocyte number) and hypertrophy (an increase in adipocyte size). Rumen-protected fatty acid supplements have been utilized to alter fat deposition, modify the fatty acid composition of meat, and reduce methane emissions. However, limited research has explored how different fatty acid mixtures influence adipose tissue’s biphasic growth phases. Methods: The objectives of this study are to investigate the effects of fatty acid mixtures (seven different mixtures) on: (1) hyperplasia of undifferentiated stromal vascular fraction (SVF) cells, or (2) hypertrophy of chemically differentiated SVF cells isolated from subcutaneous adipocytes of finished steers. Results: Mixtures containing palmitic and linoleic acids stimulated hyperplasia, enhancing the proliferation of undifferentiated SVF cells, while mixtures with oleic acid (50%) predominantly promoted hypertrophy, driving lipid accumulation and adipocyte maturation. Conversely, mixtures composed solely of saturated fatty acids (50% palmitic and 50% stearic acids) exhibited a profound inhibitory effect on both hyperplasia and hypertrophy, underscoring the importance of fatty acid composition in regulating adipogenesis. Conclusions: These findings demonstrate that the composition of fatty acid mixtures directly influences adipogenesis and lipogenesis in vitro, highlighting their potential role in designing tailored rumen-protected supplements for modifying fat deposition in livestock. Full article

The use of autologous biological preparations (ABPs) and their combinations fills the void in healthcare treatment options that exists between surgical procedures, like plastic reconstructive, cosmetic, and orthopedic surgeries; non-surgical musculoskeletal biological procedures; and current pharmaceutical treatments. ABPs, including high-density platelet-rich plasma (HD-PRP), bone marrow aspirate concentrates (BMACs), and adipose tissue preparations, with their unique stromal vascular fractions (SVFs), can play important roles in tissue regeneration and repair processes. They can be easily and safely prepared at the point of care. Healthcare professionals can employ ABPs to mimic the classical wound healing cascade, initiate the angiogenesis cascade, and induce tissue regenerative pathways, aiming to restore the integrity and function of damaged tissues. In this review, we will address combining autologous HD-PRP with adipose tissue, in particular the tissue stromal vascular fraction (t-SVF), as we believe that this biocellular combination demonstrates a synergistic effect, where the HD-PRP constituents enhance the regenerative potential of t-SVF and its adipose-derived mesenchymal stem cells (AD-MSCs) and pericytes, leading to improved functional tissue repair, tissue regeneration, and wound healing in variety of clinical applications. We will address some relevant platelet bio-physiological aspects, since these properties contribute to the synergistic effects of combining HD-PRP with t-SVF, promoting overall better outcomes in chronic inflammatory conditions, soft tissue repair, and tissue rejuvenation. Full article