Search Results (2,075)

Background/Objectives: Mesenchymal stem cells (MSCs) are deemed to be a highly safe model for autologous and allogeneic cellular therapy, owing to their inherent lack of HLA-DR expression, immunomodulatory properties, homing ability, and plasticity allowing differentiation into different cell types. The interest in activating autophagic signaling in MSCs has recently grown due to its significant potential in maintaining stemness, enhancing paracrine signaling, and providing therapeutic benefits for cancer and neurodegenerative diseases. This study aimed to explore the impact of autophagy induction on enhancing the therapeutic potential of MSCs by maintaining their plasticity and to assess different induction agents. Methods: In this study, MSCs were first extracted from the fat tissue of Sprague–Dawley (SD) rats and characterized phenotypically and molecularly by their positive expression of stemness markers CD29, CD106, and CD44, and their negative expression of hematopoietic surface markers CD14, CD34, and CD45, using a flow cytometry approach. Isolated MSCs were then treated separately with two FDA-approved autophagy inducers: Lithium Chloride and Trehalose, following assessment of autophagy activity. Results: Treated MSCs showed significant increases in autophagic activity at both the transcriptional and translational levels. The successful induction of autophagy in MSCs was confirmed through the elevated expression of autophagy-related genes such as ATG3, ATG13, ATG14, P62, and ULK1. These data were confirmed by the significant upregulation in LC3 protein expression and the formation of autophagosomes, which was detected using a transmission electron microscope. Furthermore, the expression of Oct4, Sox2, and Nanog genes was significantly enhanced after treatment with Trehalose and Lithium Chloride compared with untreated control MSCs which may indicate an upregulation of pluripotency. Meanwhile, Lithium Chloride and Trehalose did not significantly induce cellular apoptosis, indicated by the Bax/Bcl-2 expression ratio, and significantly decreased the expression of the antioxidant markers SOD and GPx. Conclusions: Treatment of MSCs with Trehalose and, in particular, Lithium Chloride significantly activated autophagic signaling, which showed a profound effect in enhancing cells’ pluripotency, reinforcing the usage of treated MSCs for autologous and/or allogenic cellular therapy. However, further in vivo studies for activating autophagy in cellular grafts should be conducted before their use in clinical trials. Full article

Background: Paroxysmal nocturnal hemoglobinuria (PNH) is a clonal hematopoietic stem cell disease characterized primarily by intravascular hemolysis, thrombosis, and bone marrow failure. Complement inhibitors are commonly used in clinical treatment and show limited efficacy, highlighting the urgent need to identify new therapeutic targets and explore alternative treatment strategies to provide theoretical guidance for clinical practice. Methods: We established a PNH cell model and constructed an miRNA–mRNA regulatory network to identify key miRNAs and core target genes. Single-cell sequencing data were analyzed to further clarify the critical genes. Finally, integrated drug database analysis identified potential therapeutic agents for PNH, which were validated by molecular docking and molecular dynamics simulations. Results: Using CRISPR/RNP technology, we successfully constructed a PIGA-knockout (PIGA-KO) THP-1 cell model. Differential expression analysis identified 1979 differentially expressed mRNAs (DEmRNAs) and 97 differentially expressed miRNAs (DEmiRNAs). The multiMiR package in R was used to predict the target genes of DEmiRNAs, from which those experimentally validated through dual-luciferase reporter assays were selected. After integration with the DEmRNAs, an miRNA–mRNA regulatory network was constructed, comprising 26 miRNAs and 38 mRNAs. Subsequent miRNA pathway enrichment analysis identified hsa-miR-23a-3p as a key miRNA, with CXCL12, CXCL8, HES1, and TRAF5 serving as core target genes. The integration of single-cell sequencing datasets (PRJNA1061334 and GSE157344) was performed, followed by cell communication and enrichment analysis. This approach, combined with clinical relevance, identified the neutrophil cluster as the key cluster. Intersection analysis of neutrophil cluster differential analysis results with key modules from hdWGCNA further clarified the critical genes. Drug prediction using EpiMed, CMap, and DGIdb identified Leflunomide, Dipyridamole, and Pentoxifylline as potential therapeutic agents. Molecular docking and molecular dynamics simulations showed stable binding of these potential drugs to the critical molecules, indicating a viable molecular interaction foundation. Conclusions: Leflunomide, Dipyridamole, and Pentoxifylline may serve as promising therapeutic agents for PNH, and the hsa-miR-23a-3p/CXCL8 regulatory axis could play a pivotal role in the pathogenesis and progression of PNH. Full article

Mesenchymal stem/stromal cells (MSCs) exhibit broad differentiation capability and strong immunoregulatory potential mediated through intercellular communication and the release of diverse paracrine mediators. They represent a promising but still investigational therapeutic approach for managing complications associated with allogeneic hematopoietic stem cell transplantation (allo-HSCT). This review provides an updated synthesis of MSC biology, their bidirectional interaction with immune cells, and their functional contribution to the hematopoietic niche. It also evaluates current clinical evidence regarding the therapeutic roles of MSCs and MSC-derived extracellular vesicles (EVs) in acute and chronic graft-versus-host disease (aGVHD/cGVHD), as well as in poor graft function. Mechanistic insights encompass macrophage polarization toward an anti-inflammatory phenotype, inhibition of dendritic cell maturation, enhancement of regulatory T-cell expansion, and modulation of cytokine signaling pathways. Within the bone marrow milieu, MSCs contribute to stromal restoration and angiogenic repair. Recent phase II/III trials in steroid-refractory (SR)-aGVHD have demonstrated overall response rates ranging from 48 to 71%. Efficacy appears particularly enhanced in pediatric patients and with early MSC administration. Across studies, MSC therapy shows a favorable safety profile; however, heterogeneity in response and inconsistent survival outcomes remain notable limitations. For poor graft function, limited prospective studies indicate hematopoietic recovery following third-party MSC infusions, and combination approaches such as co-administration with thrombopoietin receptor agonists are under investigation. MSC-derived EVs emulate many immunomodulatory effects of their parental cells with a potentially safer profile, though clinical validation remains in its infancy. MSC-oriented interventions hold substantial biological and therapeutic promise, offering a favorable safety margin; however, clinical translation is hindered by product variability, suboptimal engraftment and persistence, and inconsistent efficacy across studies. Future directions should emphasize standardized manufacturing and potency assays, biomarker-driven patient and timing selection, optimized conditioning and dosing strategies, and the systematic appraisal of EV-based or genetically modified MSC products through controlled trials. Full article

Myeloid neoplasms (MNs) with germline predisposition represent a distinct, increasingly recognized category in the WHO classification, encompassing myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML) arising in the context of an inherited genetic alteration or mutation. While often presenting at a younger age or with characteristic cytopenias with or without organ dysfunction, some can manifest in adulthood, highlighting the need for vigilance regardless of age or family history. Key predisposing genes include transcription factors (e.g., RUNX1, CEBPA) and genes involved in RNA splicing and telomere biology disorders. Identification of these germline mutations is critical as MNs with germline predisposition dictate specific therapeutic strategies—particularly for hematopoietic stem cell transplantation (HSCT)—and require genetic counseling and surveillance for at-risk relatives. Accurate diagnosis often requires non-hematopoietic germline DNA testing, which provides important biological insights into the development of different myeloid neoplasms and directs personalized patient care. Full article

Bone metastases mark a critical and often terminal phase in cancer progression, where disseminated tumor cells (DTCs) manage to infiltrate and exploit the complex microenvironments of the bone marrow. While most current therapies focus on the well-known late-stage “vicious cycle” of osteolysis, they often overlook the earlier stages, namely, tumor cell colonization and dormancy. During these early phases, cancer cells co-opt hematopoietic stem cell (HSC) niches, using them as sanctuaries for long-term survival. In this review, we bring together emerging insights that highlight a trio of underappreciated cellular players in this metastatic takeover: megakaryocytes, erythroid lineage cells, and perivascular stromal subsets. Far from being passive bystanders, these cells actively shape the metastatic niche. For instance, megakaryocytes and platelets go beyond their role in transport; they orchestrate immune evasion and dormancy through mechanisms such as transforming growth factor-β1 (TGF-β1) signaling and the physical shielding of tumor cells. In parallel, we uncover a distinct “erythroid-immune” axis: here, stress-induced CD71⁺ erythroid progenitors suppress T-cell responses via arginase-mediated nutrient depletion and checkpoint engagement, forming a potent metabolic barrier against immune attack. Furthermore, leptin receptor–positive (LepR⁺) perivascular stromal cells emerge as key structural players. These stromal subsets not only act as anchoring points for DTCs but also maintain them in protective vascular zones via CXCL12 chemokine gradients. Altogether, these findings reveal that the metastatic bone marrow niche is not static; it is a highly dynamic, multi-lineage ecosystem. By mapping these intricate cellular interactions, we argue for a paradigm shift: targeting these early and cooperative crosstalk, whether through glycoprotein-A repetitions predominant (GARP) blockade, metabolic reprogramming, or other niche-disruptive strategies, could unlock new therapeutic avenues and prevent metastatic relapse at its root. Full article

Systemic sclerosis (SSc) is a disease in which malfunctioning immune cells lead to the formation of autoantibodies that damage blood vessels and body tissues. Fibrosis then develops in the affected organs. Its complex pathogenesis involves multiple immune and stromal cell types, soluble mediators, and dysregulated tissue repair, resulting in heterogeneous clinical manifestations and poor prognosis. Current disease-modifying therapies provide only modest benefits, often slowing but rarely reversing disease progression, and are associated with considerable adverse effects. These limitations have spurred the development of cell-based therapeutic strategies aimed at restoring immune tolerance and promoting tissue repair. In this review, we summarize recent advances in hematopoietic stem cell transplantation, mesenchymal stem cell therapy, and adoptive regulatory T cell transfer and highlight the emerging role of chimeric antigen receptor (CAR)-T cell therapy as a transformative approach for SSc. Collectively, these evolving strategies hold the potential to improve survival, achieve durable remissions, and significantly enhance quality of life for patients with SSc. Full article

Germline genetic testing plays a critical role in diagnosing inherited predispositions and increasingly guides therapeutic and surveillance choices—but becomes technically challenging after allogeneic hematopoietic stem cell transplantation (HSCT), when donor-derived DNA contaminates host tissues. To address this, we compared donor-derived DNA across three accessible tissues—buccal swab, nail, and eyebrow follicles—in recipients after hematopoietic stem cell transplantation using two orthogonal assays (34-SNP next-generation sequencing and a 27-marker short tandem repeat panel) and modeled clinical covariates that influence chimerism. Eyebrow follicles showed consistently low donor DNA (median 1% by NGS; 3% by STR) whereas buccal swabs and nails carried substantially higher donor fractions (+25 and +22 percentage points versus eyebrow, respectively; both p < 0.01). Across methods, STR yielded on average ≈6 percentage points higher donor fractions than NGS at low-level chimerism. Several transplant covariates correlated with chimerism: matched-related donors and a perfect HLA match (10/10) were each associated with lower donor DNA (≈12–14 and 15–20 percentage points, respectively); longer times since hematopoietic stem cell transplantation correlated with lower levels for nail samples, and donor–recipient sex match correlated with higher donor DNA (~7–8 percentage points). Even low-level chimerism can distort germline variant interpretation. We propose a pragmatic protocol for post-hematopoietic stem cell transplantation germline testing that prioritizes eyebrow follicles as the default tissue. An SNP-based quality control assay is used to flag unsafe donor fractions (≥ 5–10%) before comprehensive germline analysis, reducing the risk that chimeric donor DNA distorts germline variant interpretation. Full article

Background: Three-dimensional (3D) culture systems use polymer particles with a bone marrow stroma cell feeder layer to reproduce a biostructural hematopoiesis state more effectively than in conventional two-dimensional (2D) culture methods. The 3D culture maintains normal hematopoiesis, resulting in prolongation of hematopoietic stem cell proliferation and differentiation, while the bone marrow stromal cells in the culture alter the growth of leukemic cells and protect them from anticancer agents. However, the effect of stromal cells on hematopoietic stem cell proliferation and differentiation and neoplastic cells, including leukemia, in 3D culture is still a point of contention. Methods: We assessed the mechanism of two different bone-marrow-derived stromal cells (i.e., MS-5 and Tst-4) with different characteristics by using a feeder layer in the 3D culture to compare their supportive action on leukemic cells, focusing on the role of 3D cultures constructed with bone marrow stromal cells in leukemic cell growth. Multiple myeloma cells are strongly related to stromal cells in their proliferation; hence, cloned MM1.S cells derived from multiple myeloma were cocultured in 3D, and their cell growth was examined. We also examined the effect of the antineoplastic agent bortezomib, a proteasome inhibitor, in the 3D culture system with a different stromal cell feeder. Results and Conclusions: When MM1.S myeloma cells were cultured with MS-5 stroma in 3D conditions, cell growth was found to be slow compared with that in 2D culture, as well as with those in both the 2D and 3D cocultures with Tst-4 stroma. Additionally, the MS-5 cells in the 3D culture protected the MM1.S cells from the cytocidal effect of the bortezomib treatment. Different MM1.S cell kinetics were observed depending on the stromal cells used, suggesting their inherent and complicated characteristics. Full article

Adult T-cell leukemia/lymphoma (ATLL) is an aggressive T-cell malignancy caused by persistent infection with human T-cell leukemia virus type 1 (HTLV-1). ATLL remains difficult to treat despite intensive chemotherapy, antiviral therapy, and hematopoietic stem cell transplantation. The limited durability of current treatment strategies highlights the need for mechanism-based therapeutic approaches. Protein arginine methyltransferase 5 (PRMT5) is a type II arginine methyltransferase that regulates transcription, RNA splicing, DNA damage responses, and immune signaling through symmetric dimethylation of histone and non-histone substrates. PRMT5 is frequently overexpressed across hematologic and solid tumors. Preclinical studies indicate that PRMT5 expression is elevated during HTLV-1-mediated T-cell transformation and that pharmacologic inhibition of PRMT5 selectively impairs the survival and transformation of infected T cells in vitro and in vivo. In this review, we highlight the current understanding of PRMT5 biology in cancer, summarize preclinical studies supporting PRMT5 as a therapeutic target in ATLL, and discuss key challenges to future clinical translation. We also discuss emerging approaches such as rational combination therapies and tumor-selective PRMT5 inhibitors as potential paths toward treatment for ATLL. Full article

Background/Objectives: Ocular graft-versus-host disease (oGVHD) is a chronic, immune-mediated complication of allogeneic hematopoietic stem cell transplantation that can progress to corneal ulceration or perforation. These cases are often refractory to standard therapy and present a high risk of graft failure after keratoplasty. We report a case of oGVHD-related corneal perforation successfully managed with a novel amniotic membrane-assisted “envelope” technique during corneal transplantation. Case Report: A 42-year-old man with chronic oGVHD and a full-thickness corneal perforation underwent urgent repair with a lamellar patch graft completely wrapped in cryopreserved amniotic membrane, followed by penetrating keratoplasty (PKP) using an amniotic membrane envelope surrounding the donor lenticule. Results: The amniotic membrane provided a 360° biological barrier that isolated graft antigens from the inflammatory environment while supporting epithelial healing and stromal remodeling. Despite recurrent inflammatory episodes and multiple procedures—including cataract extraction, pars plana vitrectomy, and multilayer amniotic membrane transplantation—the graft remained clear and stable at 12-month follow-up, achieving a best-corrected visual acuity of 20/40. Conclusions: The amniotic membrane envelope technique may represent a valuable adjunct in managing high-risk corneal perforations secondary to oGVHD. By combining immune modulation and regenerative support, this approach can enhance tectonic stability, reduce rejection risk, and promote durable surface recovery, potentially delaying or avoiding keratoprosthesis in refractory cases. Full article

Myeloproliferative neoplasms (MPNs) are a heterogeneous group of diseases originating from hematopoietic stem cell transformation, characterized by the clonal proliferation of hematopoietic progenitors. A specific subset includes myeloid/lymphoid neoplasms with eosinophilia and tyrosine kinase (TK) gene fusions, particularly involving PDGFR A or B, which are sensitive to TK inhibitor treatment. We report a case of a 21-year-old patient with a myeloproliferative/myelodysplastic neoplasm, presenting with hyperleukocytosis, anemia, thrombocytopenia, and elevated LDH. The peripheral blood smear showed hypogranular neutrophils, eosinophils, basophils, and myeloid precursors. The absence of BCR::ABL1 and mutations in JAK2, CALR, and MPL excluded common MPNs. Cytogenetic analysis revealed a rearrangement between chromosomes 5 and 14. FISH analysis confirmed an inverted insertion from chromosome 5 to chromosome 14, involving the PDGFRB gene. WGS and RNAseq identified a fusion between PDGFRB and CCDC88C, causing the constitutive activation of PDGFRB. The fusion gene was confirmed by sequencing. This allowed for targeted therapy with a tyrosine kinase inhibitor (TKI), leading to molecular remission monitored by RT-qPCR. This case highlights how a multidisciplinary approach can identify atypical transcripts in MPN, guiding targeted therapy with TK inhibitors, thus resulting in effective treatment and molecular remission. Full article

Human cytomegalovirus (HCMV) infection is a significant complication in transplant recipients. Following HCMV reactivation, the recovery of T-cell responses serves as a key indicator of protection from HCMV disease. This study aimed to assess the HCMV-specific CD4⁺ and CD8⁺ T-cell responses and their cytokine production (IFNγ, TNFα, IL2) against various HCMV proteins (IE-1, pp65, gB, gH/gL/pUL128L) in solid organ transplant recipients (SOTRs) and hematopoietic stem cell transplant recipients (HSCTRs) with active HCMV infection. The cohort consisted of 16 SOTR and 16 HSCTR categorized into two groups: (i) Controllers, who spontaneously controlled the infection, and (ii) Non-Controllers, who required antiviral treatment. T-cell responses were analyzed following stimulation with peptide pools and intracellular cytokine staining. Prior to transplantation, all patients exhibited a significantly higher frequency of CD4⁺ T cells specific to pp65 compared to gH and gL/pUL128L. During the peak of infection, T-cell frequencies across all peptides were similar, but at infection resolution, the frequency of pp65 and gB-specific CD4⁺IFNγ⁺ T cells was significantly higher than gL/pUL128L. Additionally, pp65 and IE-1-specific CD8⁺IFNγ⁺ T-cell responses were significantly greater than those against gH and gL/pUL128L at the resolution of infection. Notably, Controllers exhibited significantly higher frequencies of monofunctional pp65-specific T cells, particularly in CD8⁺ T cells producing IFNγ and TNFα. The response to pp65, especially IFNγ production, may serve as a key marker for identifying patients capable of controlling HCMV infection. Full article

Multiple sclerosis (MS) is a heterogeneous autoimmune disease driven by peripheral immune dysregulation and compartmentalized central nervous system (CNS) inflammation. Despite more than 20 approved disease-modifying therapies, disability accrual remains common, particularly in patients with highly active relapsing disease and progressive phenotypes characterized by silent progression and smoldering neuroinflammation. Two emerging therapeutic strategies address these unmet needs: Bruton’s tyrosine kinase (BTK) inhibitors and autologous haematopoietic stem cell transplantation (HSCT). Although mechanistically distinct, both aim to overcome limitations of conventional immunosuppression by intervening more deeply in the autoimmune cascade. This narrative review synthesized mechanistic, clinical, and translational evidence identified through a comprehensive search of PubMed, Scopus, Web of Science, and ClinicalTrials.gov from January 2010 to August 2025. BTK inhibitors are oral, CNS-penetrant therapies that selectively modulate B-cell signaling and CNS-resident myeloid cells without broad lymphocyte depletion, enabling continuous immunomodulation. Phase II–III trials of evobrutinib, tolebrutinib, and fenebrutinib show consistent MRI activity suppression but variable effects on relapses and disability, suggesting relevance in microglial-driven, relapse-independent disease. HSCT is a one-time immune reconstitution therapy that eradicates autoreactive immune clones and restores immune tolerance. Randomized and real-world studies demonstrate profound suppression of inflammatory activity, stabilization or improvement of disability, and durable treatment-free remission in selected patients with highly active relapsing–remitting MS, although procedure-related risks require strict eligibility criteria and experienced centers. Together with BTK inhibitors, HSCT represents a complementary strategy within an increasingly personalized MS treatment paradigm, emphasizing biomarker-guided patient selection and optimized therapeutic sequencing. Full article

Recent studies support that hematopoietic stem cell (HSC)-derived myeloid dendritic cells, monocytes/macrophages (Mo/Mϕ), and osteoclast precursors (OCps) share common progenitor(s) during development. This occurs mainly through receptor activator of NF-κB ligand (RANKL) signaling via its cytoplasmic adaptor protein complex (TRAF6) to subsequent osteoclastogenesis for bone loss and/or remodeling. Presently, mounting new evidence suggests that erythro-myeloid progenitor (EMP)-derived macrophages (Mϕ) and HSC-derived monocytes (Mo) produce embryonic, fetal, and postnatal OCp pools (i.e., primitive OCp), pinpointing a complex network of multiple OCp developmental origins. However, their ontogenic developments, lineage interactions, and contributions to the alternative osteoclastogenesis—in contrast to overall bone remodeling or loss—remain elusive. Interestingly, studies have also elucidated the contributions of immature CD11c⁺ myeloid DC-like OCps to osteoclastogenesis, with or without the classical so-called Mo/Mϕ-derived OCp subsets, and described that CD11c⁺ myeloid DCs (mDCs) develop into functionally active OCs; meanwhile, the cytokine TGF-β mediates a stepwise regulation of de novo immature mDCs/OCps through distinct crosstalk(s) with IL-17, an unrecognized interaction featuring TRAF6^(−/−)CD11c⁺ mDDOCps that coexist and proficiently colocalize in the local environment to drive a bona fide route for alternative osteoclastogenesis in vivo. Collectively, new findings—critically hinged on progenitor osteoclastogenic pathways (primitive OCps, mDCs/OCps, osteomorphs, etc.) and involving classical and/or alternative routes to inflammation-induced bone loss—are discussed via the illustrated schemes. This review highlights plausible ontogenic vs. principal or alternative developmental paths and their consequential downstream effects. Full article

Background: Higher-risk myelodysplastic syndromes (HR-MDS) carry a high risk of progression to acute myeloid leukemia and poor overall survival. Hypomethylating agents (HMAs), such as azacitidine, remain the standard of care but have limited efficacy. A 15-day venetoclax-azacitidine regimen has shown promising objective response rates (ORR) and potential as a bridge to allogeneic hematopoietic stem cell transplantation (HSCT) in relapsed/refractory HR-MDS. We conducted a prospective multicenter trial to evaluate its efficacy and safety in previously untreated patients. Methods: This multicenter prospective study enrolled treatment-naïve HR-MDS patients (IPSS-R > 3.5). Venetoclax was administered on days 1–15 (escalated from 100 to 400 mg), combined with azacitidine (75 mg/m²) on days 1–7 of each 28-day cycle. The primary endpoint was ORR (2006 IWG criteria); secondary endpoints included complete remission (CR), overall survival (OS), and AML progression. Results: Twenty-eight patients (median age: 63 years) were enrolled, with a median follow-up of 8.5 months. ORR was 85.7% per 2006 IWG (CR: 35.7%, marrow CR: 50.0%), and 78.6% per 2023 IWG (CR: 35.7%). Responses were consistent across molecular and IPSS-R subgroups. Median OS was not reached. High neutrophil count and high cytogenetic risk were favorable factors; TP53 mutation/deletion was an adverse prognostic marker. Grade 3–4 hematologic toxicities included neutropenia (96.4%), anemia (71.4%), and thrombocytopenia (64.3%). Serious adverse events (35.7%) were mainly infections. No dose-limiting or unexpected toxicities were observed. Conclusions: The 15-day venetoclax plus azacitidine regimen demonstrated high efficacy and manageable toxicity in treatment-naïve HR-MDS. It may be particularly beneficial for patients with high neutrophil counts, adverse cytogenetics, or those eligible for HSCT, supporting further investigation in larger trials. Full article