Biological functions of mesenchymal stem cells and clinical implications

CD34+CD45+ cells promote alveolar macrophage efferocytosis to alleviate phosgene-induced acute lung injury in rats

Phosgene is still widely used in industrial production nowadays. However, as a toxic gas, accidental exposure to phosgene can lead to acute lung injury (ALI). Our team previously identified a cell subpopulation as CD34+CD45+ cells in the bronchoalveolar lavage fluid (BALF) of rats. CD34+CD45+ cells were demonstrated to possess stem cell properties and alleviate pulmonary inflammation during phosgene-induced acute lung injury (P-ALI). However, how CD34+CD45+ cells contribute to the anti-inflammatory process remains unexplored. Rats with P-ALI were intratracheally administered with CD34+CD45+ cells, and it was found that both the infiltration of macrophages and apoptotic cells were reduced in the lung tissues. The macrophages were polarized to an anti-inflammatory CD45+CD3-CD163+MHC-IIlo phenotype and restored efferocytosis efficiency, with a decreased level of inflammatory cytokines in the BALF. Moreover, it was observed that CD34+CD45+ cells promoted macrophage efferocytosis ex vivo and in vitro. Exosomes derived from CD34+CD45+ cells were further demonstrated to mediate the enhancement of macrophage efferocytosis. The small RNA sequencing analysis suggested that exosomal rno-miR-149-5p contributed to the effect. The transfection of rno-miR-149-5p mimic induced the enhancement of efferocytosis in macrophages as the exosomes did, while rno-miR-149-5p inhibitor attenuated the effect by exosomes. Our findings provide convincing evidence that CD34+CD45+ cells can alleviate ALI by enhancing macrophage efferocytosis, offering valuable insights into their therapeutic potential in managing chemical-induced acute lung injuries.

Melatonin Promotes Osteogenic Differentiation of Rat Adipose-Derived Stem Cells via the p38/MAPK Signaling Pathway

While adipose-derived stem cells (ADSCs) transplantation represents an appealing therapeutic strategy for bone defect repair, the osteogenic capacity of ADSCs is largely limited. Melatonin has been demonstrated to contribute to the bone marrow stem cell (BMSC) osteogenesis. However, its effect on the osteogenic differentiation of ADSCs has not yet been determined. This study aims to identify whether melatonin exerts influences on the osteogenic differentiation in rat ADSCs. Rat ADSCs were isolated and identified. Subsequently, the impact of melatonin on the proliferation of rat ADSCs was examined. The effects of melatonin on the phenotypic features as well as marker genes and proteins of osteogenic differentiation were determined through the use of alkaline phosphatase (ALP) staining, ALP activity assay, alizarin red staining (ARS), RT-qPCR, western blot assay, and cellular immunofluorescence assay. To investigate the potential molecular mechanism through which melatonin promotes osteogenic differentiation of rat ADSCs, RNA sequencing, MAPK signaling pathway blocking assay and p38 mRNA interference assay were carried out. The results showed that melatonin at concentrations of 0-100 μM was safe and nontoxic for the proliferation of rat ADSCs, with the concentration at 100 μM exhibiting the most pronounced osteogenesis. Additionally, melatonin was observed to activate the p38/MAPK signaling pathway in rat ADSCs. Moreover, the p38/MAPK pathway inhibitor (SB203580) and siRNA targeting p38 mRNA (p38 siRNA) were found to inhibit the melatonin-promoted osteogenic differentiation of rat ADSCs. In conclusion, the results of this study indicate that melatonin promotes osteogenic differentiation of rat ADSCs through the activation of the p38/MAPK signaling pathway. In light of these findings, melatonin treatment represents an effective strategy for promoting osteogenic differentiation of ADSCs.

ROS-Responsive Hydrogel Delivering METRNL Enhances Bone Regeneration via Dual Stem Cell Homing and Vasculogenesis Activation

Critical-sized bone defects arising from bone-related diseases pose a clinical challenge, exceeding the body's natural healing capacity. Evidence has shown that a disordered microenvironment characterized by reactive oxygen species (ROS) overproduction, vascular damage, and osteoblast deficiency severely hinders bone repair. Therefore, the reconstruction of microenvironmental homeostasis post-injury is of utmost importance. Herein, a ROS-responsive scavenging GelMA loaded with METRNL (RRG-MRL) is developed, serving as a "bone microenvironment-modulating system" for targeted delivery of METRNL, which stimulates bone marrow mesenchymal stem cells (BMSCs) homing and angiogenic sprouting. Upon exposure to elevated levels of ROS within the defect region, ROS-cleavable NHS-TK-NHS linkers are disrupted, triggering responsive degradation and METRNL release. This treatment significantly reduced ROS levels and alleviated inflammation, along with increasing the levels of anti-apoptotic factors. Meanwhile, released METRNL induced endothelial cell angiogenesis by activating the c-Kit/PI3K/Akt pathway and increased secretion of SDF-1α (CXCL12) to promote BMSCs recruitment. Rat models of cranial bone defects treated with RRG-MRL demonstrated reduced ROS signal intensity in situ, increased endogenous BMSCs count, and enhanced neovascularization, resulting in accelerated bone regeneration. The proposed platform offers a multistage therapeutic approach facilitating rapid reconstruction of microenvironment homeostasis to promote bone regeneration, indicating significant clinical potential.

A meta-analysis on application and prospect of cell therapy in the treatment of diabetes mellitus

OBJECTIVE

Diabetes mellitus (DM) is a grave autoimmune disorder because of no insulin self-generation. Currently, mainly clinical methods exist, serious adverse effects leading to stem cell therapy are considered. The mesenchymal stem cells (MSCs), require high differentiation capacity and are judged as crucial in DM treatment. The meta-analysis aimed to systemically analyze the particular types of MSCs which play a more important role in DM and which DM is treated more effectively.

METHOD

A systematic review was conducted on the published literature, clinical trials and observational studies, utilizing databases such as PubMed, Embase, Cochrane and clinicaltrial.gov. RevMan software was adopted to draw Forest Plot and Funnel Plot, and subgroup analysis were employed to evaluate heterogeneity between different groups.

RESULTS

We identified the meta-analyses of 34 unique random controlled trials and divided our own systematic reviews into 8 groups. The MSCs were associated with placebo (OR = 2.79, 95% CI [1.63, 4.75]), Standard Clinical Treatment (SCT) (OR = 4.12, 95% CI [2.76, 6.14]), and monocyte (OR = 6.52, 95% CI [3.56, 9.48]). The comparison between Autologous MSCs and Allogenic MSCs (OR = 4.64, 95% CI [3.42, 6.31]), Autologous BMMSCs and other MSCs (OR = 5.28, 95% CI [3.64, 7.66]), Allogenic ASCs and UCMSCs (OR = 3.54, 95% CI [1.83, 6.86]), Type I DM and Type II DM (OR = 3.10, 95% CI [1.79, 5.38]), intravenous injection and other injections (OR = 4.81, 95% CI [3.34, 6.94]), diabetic foot ulcers and diabetic neurological disease (OR = 3.88,,95% CI [2.53,5.95]).

CONCLUSION

Current evidence suggests that MSCs hold significant potential for treating DM, demonstrating considerably high safety and efficacy. MSCs exhibit higher therapeutic benefits compared to monocytes, with autologous MSCs offering better clinical outcomes than allogenic sources. MSCs (BMMSCs) proved more effective than other types of MSCs. However, no significant differences were observed between adipose-derived MSCs (ASCs) and umbilical cord-derived MSCs (UCMSCs) in the allogeneic setting. Moreover, MSCs show more pronounced therapeutic effects in Type II DM, and the difference among the injection methods is minimally observed. In conclusion, the research scope on DM is relatively limited in this study and further research is necessary to improve the reliability of the estimates.

"Remodeling the intestinal immune microenvironment": immune regulation and tissue regeneration by mesenchymal stem/stromal cells in the repair microenvironment of inflammatory bowel disease

The global prevalence of inflammatory bowel disease (IBD) has significantly increased in recent decades. IBD is a long-term, recurring, gastrointestinal inflammatory condition that mainly comprises two primary clinical types: ulcerative colitis and Crohn's disease. The current treatment paradigm for IBD primarily focuses on symptom management. However, this approach does not support mucosal epithelial repair, maintenance of barrier homeostasis, or regulation of biological functions in the gut. Conventional therapies rely on the frequent use of high-dose medications, including antibiotics, nonsteroidal anti-inflammatory drugs, biological agents, and immunomodulators. Recently, mesenchymal stem/stromal cells (MSCs) have gained interest in tissue regeneration owing to their unique ability to differentiate and secrete regulatory factors, including extracellular vesicles (EVs), which play crucial roles in abnormal organization. Various routes of administration have been explored in preclinical and clinical studies to deliver MSCs from diverse tissue sources. The routes include intraperitoneal, intravenous, and local (intracolonic or rectal) delivery. The MSCs employed were obtained from various tissues, including bone marrow, umbilical cord, and adipose tissue. This article reviews the research framework for the application of MSCs and EVs secretion in the treatment of IBD, emphasizing key immunological effects, such as immune microenvironment regulation, intestinal barrier stabilization, and therapeutic approaches targeting intestinal barrier disorders. The discussion primarily focuses on the advantages of MSCs over other biologics, impairment of gut mucosal tissue-resident mesenchymal stem cells in IBD development, immune targets (at the cellular and molecular levels) within the framework of IBD, and the reparative effects of MSCs in the microenvironment of IBD. We aimed to present an overview of the current trends in MSC research and therapy, as well as to identify the challenges and future directions that must be addressed to advance research on MSC-mediated therapeutic strategies for IBD.

Mesenchymal Stem Cell-Derived Exosomes Hold Promise in the Treatment of Diabetic Foot Ulcers

Diabetic foot ulcers (DFU) represent one of the most common side effects of diabetes, significantly impacting patients' quality of life and imposing considerable financial burdens on families and society at large. Despite advancements in therapies targeting lower limb revascularization and various medications and dressings, outcomes for patients with severe lesions remain limited. A recent breakthrough in DFU treatment stems from the development of mesenchymal stem cells (MSCs). MSCs have shown promising results in treating various diseases and skin wounds due to their ability for multidirectional differentiation and immunomodulation. Recent studies highlight that MSCs primarily repair tissue through their paracrine activities, with exosomes playing a crucial role as the main biologically active components. These exosomes transport proteins, mRNA, DNA, and other substances, facilitating DFU treatment through immunomodulation, antioxidant effects, angiogenesis promotion, endothelial cell migration and proliferation, and collagen remodeling. Mesenchymal stem cell-derived exosomes (MSC-Exo) not only deliver comparable therapeutic effects to MSCs but also mitigate adverse reactions like immune rejection associated with MSCs transplantation. This article provides an overview of DFU pathophysiology and explores the mechanisms and research progress of MSC-Exo in DFU therapy.

Identification of the crucial roles of BAXhigh NK cells in human derived mesenchymal stem cell therapy for chronic heart failure patients

Mesenchymal stem cells (MSCs) have demonstrated significant potential in heart failure (HF) treatment, but the exact mechanisms are still not fully understood. This research utilized single-cell RNA sequencing to examine alterations in peripheral blood mononuclear cells from heart failure patients pre- and post-MSC therapy. Moreover, we utilized Mendelian randomization (MR) analysis to identify causal genes linked to HF. Specifically, through scRNA-seq, we observed a progressive increase in Natural Killer (NK) cells within peripheral blood mononuclear cells (PBMCs) following MSC treatment. Furthermore, MR analysis identified the differentially expressed gene (DEG) BAX as a potential target gene for HF. Notably, the expression of BAX was significantly downregulated after MSC treatment, suggesting its potential as a therapeutic response biomarker. Cell-cell communication analysis revealed that BAXhigh NK cells displayed reduced cell-cell communication and increased apoptotic activity. Enrichment analysis indicated an association between BAXhigh NK cells and the "coagulant" pathway. Taken together, our findings suggest that BAX may contribute to the pathogenesis of HF by promoting coagulation and apoptotic pathways. In contrast, MSCs appear to suppress BAX expression, thereby inhibiting these pathways. MSC treatment increases the proportion of NK cells and reduces BAXhigh NK cells, ultimately improving NK cell function, and ameliorating HF.

Protective Effects of Rat Bone Marrow Mesenchymal Stem Cells-Derived Fusogenic Plasma Membrane Vesicles Containing VSVG Protein Mediated Mitochondrial Transfer on Myocardial Injury In Vitro

Overexpression of spike glycoprotein G of vesicular stomatitis virus (VSVG) can induce the release of fusogenic plasma membrane vesicles (fPMVs), which can transport cytoplasmic, nuclear, and surface proteins directly to target cells. This study aimed to investigate the roles of rat bone marrow mesenchymal stem cells (rBMSCs)-derived fPMVs containing VSVG protein in myocardial injury and their related mechanisms. The plasmids of pLP-VSVG were used to transfect rBMSCs, and then fPMVs were obtained by mechanical extrusion. After that, H9c2 cells were first treated with hypoxia reoxygenation (HR) to establish a cardiomyocyte injury model, and then were treated with fPMVs to evaluate the rescue of rBMSCs-derived fPMVs on HR-induced cardiomyocyte injury. FPMVs containing VSVG protein were successfully prepared from rBMSCs with VSVG overexpression. Compared with control fPMVs, ACTB, HDAC1, VSVG, CD81, MTCO1, and TOMM20 were significantly up-regulated (p < 0.05), while eEF2 was significantly down-regulated (p < 0.05) in the fPMVs containing VSVG protein. Additionally, it was obvious fPMVs could carry mitochondria into H9c2 cells, and HR treatment significantly inhibited viability and induced apoptosis of H9c2 cells, as well as significantly increased the contents of TNF-α and IL-1β, and ROS levels both in cells and cellular mitochondria, while evidently reducing the levels of ATP, MRCC IV, and MT-ND1 (p < 0.05). However, fPVMs could remarkably reverse the changes in these indexes caused by HR (p < 0.05). RBMSCs-derived fPMVs containing VSVG protein may have protective effects on myocardial injury by mediating mitochondrial transfer and regulating mitochondrial functions.

NGF regulates survival and differentiation of umbilical mesenchymal stem/stromal cells into GABAergic, dopaminergic and cholinergic lineages

Mesenchymal stem cells advantageous properties have led scientists to conduct trials on a range of medical conditions, including incurable neurodegenerative diseases. Wharton-Jelly derived mesenchymal stem cells, given their ease of collection, are frequently selected for these studies. This research aimed to investigate the effects of nerve growth factor (NGF) gene overexpression on the neural differentiation, survivability, and gene and protein expression of these cells. The level of gene expression was tested using the ddPCR method. Six umbilical cords from donors were collected, and three randomly chosen primary cultures of Wharton-Jelly derived mesenchymal stem cells were used in experiment. Cells were transduced with lentiviral vectors and underwent a 12-day differentiation process. The results revealed neuron-like cells with significantly high expression of CHAT, GAD2 and TH genes. A corresponding increase in protein expression was also observed. Immunostaining demonstrated notable differences in neuron-like phenotypes, contingent on the environmental conditions of the research groups. Throughout the experiment, samples with transduced mesenchymal stem cells overexpressing the NGF gene showed the highest expression levels from almost all of studied genes and proteins, and were also the most phenotypically similar to neuron-like cells. The study concluded that sustained overexpression of NGF: guides mesenchymal stem cells towards the neural pathway, facilitates the differentiation of modified mesenchymal stem cells into GABAergic, dopaminergic, and cholinergic neuron-like cells, suggests that GABAergic neurons' marker predominantly co-expresses with other neurons' markers, such as cholinergic or dopaminergic ones, increases survivability of modified mesenchymal stem cells in toxic conditions; The limitations of the study is that we merely know that cells have begun to express neurogenic markers, but in the absence of standards for mature neuronal markers, we do not yet know how far they have progressed as differentiating cells.

Immunological Safety Evaluation of Exosomes Derived From Human Umbilical Cord Mesenchymal Stem Cells in Mice

Mounting evidence indicates that exosomes derived from human umbilical cord mesenchymal stem cells (hucMSCs-exosomes) combine the advantages of hucMSC pluripotency with their nanoscale dimensions, enhancing their clinical potential through prolonged circulation half-life. Despite these promising characteristics, research on their immunological toxicity remains insufficient. This study focuses on the impact of hucMSC-exosomes on the general toxicity and immunopathological indicators. When mice received tail vein injections of 6 × 1010 hucMSC-exosomes particles, we observed no significant changes in body weight, feed intake, blood composition, organ indices, or histopathological findings throughout the 14 days observation period. Similarly, blood levels of immunoglobulins, cytokines, and lymphocyte subpopulations remained stable. The hucMSC-exosomes produced no detectable negative effects on immune organs including the thymus, spleen, and bone marrow. These findings indicate that intravenous administration of 6 × 1010 particles of hucMSC-exosomes appears relatively safe at the murine level. This assessment of safety and immunological impact following intravenous hucMSC-exosomes infusion offers experimental support for potential clinical applications and future analyses in this field.

Rapamycin ameliorates senescence of periodontal ligament stem cells and promotes their osteogenesis via the PI3K/AKT pathway

Periodontal ligament stem cells (PDLSCs) have been regarded as ideal candidates for tissue regeneration due to their excellent self-renewal and multipotent differentiation ability. Rapamycin (RAPA) is reported to play an important role in the regulation of biological properties of stem cells and a variety of physiological processes. This study investigates whether RAPA could ameliorate the senescence and accelerate the osteogenic differentiation of PDLSCs, particularly the regenerative potential in a rat calvarial bone defect model, and the underlying mechanisms involved. β-galactosidase staining, quantitative real-time polymerase chain reaction, and western blot analysis were performed to assess the effects of RAPA on senescent PDLSCs. The osteogenic differentiation ability of PDLSCs was detected by alkaline phosphatase staining and activity, Alizarin Red S staining, and gene and protein levels of osteogenesis-related markers. The underlying signaling pathways were investigated via RNA transcriptome sequencing analysis and WB tests. Calvarial bone defects in rat were treated with PDLSCs pre-incubated with or without RAPA and/or H2O2. The results showed that RAPA could enhance the osteogenic potentials of PDLSCs via PI3K/AKT signaling pathway, and reversed H2O2-induced senescence and osteogenic differentiation inhibition of PDLSCs. Moreover, calvarial defects transplanted with RAPA-treated PDLSCs showed significantly greater new bone formation compared with other groups, and also improved the H2O2-induced impairment of bone formation, whether by micro-computed tomography examination or by histological analysis. Collectively, RAPA was capable of promoting osteogenic differentiation of PDLSCs via PI3K/AKT signaling pathway in vitro, facilitating calvarial bone regeneration and reversing H2O2-induced impairment of osteogenic differentiation and cell senescence in PDLSCs.

Zinc finger protein 750 is a novel regulator of osteoblast differentiation and bone homeostasis by transcriptionally deactivating SNAI1 signaling

Zinc finger protein 750 (ZNF750) has been identified as a potential tumor suppressor across multiple malignancies. Nevertheless, the specific involvement of ZNF750 in the regulation of mesenchymal cell differentiation and bone homeostasis has yet to be elucidated. In the current study, we observed a substantial presence of ZNF750 in bone tissue and noted alterations in its expression during osteogenic differentiation of mesenchymal progenitor cells. Functional experiments indicated that ZNF750 promoted osteogenic differentiation while impeding adipogenic differentiation from mesenchymal stem/progenitor cells. Further mechanistic investigations revealed that ZNF750 transcriptionally suppressed the expression of Snail family transcriptional repressor 1 (SNAI1) by binding to the proximal promoter region of Snai1 gene, thereby activating Wnt/β-catenin signaling. SNAI1 exerted opposing effects on cell differentiation towards osteoblasts and adipocytes in comparison to ZNF750. The overexpression of SNAI1 counteracted the dysregulated osteogenic and adipogenic differentiation induced by ZNF750. Furthermore, the transplantation of Znf750-silenced bone marrow stromal cells into the marrow of wild-type mice resulted in a reduction in cancellous and cortical bone mass, alongside a decrease in osteoblasts and an increase in marrow adipocytes, while the number of osteoclasts remained unchanged. This study presents the first demonstration that ZNF750 regulates the differentiation of osteoblasts and adipocytes from mesenchymal stem/progenitor cells by transcriptionally deactivating SNAI1 signaling, thereby contributing to the maintenance of bone homeostasis. It suggests that ZNF750 may represent a promising therapeutic target for metabolic bone disorders such as osteoporosis.

Review on Current Advancements in Facilitation of Burn Wound Healing

Burns are common injuries, but their treatment remains challenging due to the complex nature of the wound healing process. Burn wounds are classified into different categories based on their size and depth. Treatment modalities vary significantly across these categories, primarily focusing on the inflammation, proliferation, and remodeling phases of burn wound healing. This review summarizes current research on various approaches to enhance burn wound recovery, including advancements in wound dressings, the use of platelet-rich plasma, stem cells, their soluble factors primarily in the form of secretomes or extracellular vesicles, and nano-technologies. Additionally, advancements in modernized traditional medicine are discussed to give a new aspect for burn wound healing. This review also summarizes the barriers in translating bench research to clinical practice in burn wound treatment methods. For an effective translation, researchers and industrial partners should work more closely, while regulatory bodies should streamline the approval procedure.

Unleashing the Potential: Exploring the Application and Mechanism of Mesenchymal Stem Cells in Autoimmune Diseases

Autoimmune diseases (AIDs) occur when the immune system mistakenly attacks the body's own antigens. Traditionally, these conditions are treated with nonspecific immunosuppressive therapies, including corticosteroids, immunosuppressants, biological agents, and human immunoglobulins. However, these treatments often fail to achieve optimal outcomes, especially for patients with severe cases. Mesenchymal stem cells (MSCs) present a promising alternative due to their robust self-renewal capabilities and multidirectional differentiation potential. MSCs are easily accessible, exhibit low immunogenicity, and can help reduce graft rejection. MSCs can inhibit T cell proliferation, reduce proinflammatory T cells, inhibit B cell differentiation, induce macrophage polarization towards the anti-inflammatory M2 phenotype, and suppress activity of natural killer (NK) cells and dendritic cells (DCs). Additionally, MSCs can regulate T cells, macrophages, and fibroblast-like synoviocytes (FLS) by releasing microRNA (miRNA) through exosomes or extracellular vesicles (EVs), thus providing therapeutic benefits for various diseases. Numerous clinical trials have highlighted the therapeutic benefits of MSCs in treating various AIDs, leading to increased interest in MSC transplantation. This review summarizes the current applications and mechanisms of action of MSCs in the treatment of AIDs.

Engineered ATP-Loaded Extracellular Vesicles Derived from Mesenchymal Stromal Cells: A Novel Strategy to Counteract Cell ATP Depletion in an In Vitro Model

The use of adenosine triphosphate (ATP) has shown promising effects in alleviating ischemic damage across various tissues. However, the penetration of ATP into kidney tubular cells presents a challenge due to their unique anatomical and physiological properties. In this study, we introduce a novel bioinspired drug delivery system utilizing extracellular vesicles (EVs) derived from mesenchymal stromal cells (MSCs) and engineered to carry ATP. ATP-loaded liposomes (ATP-LPs) and ATP-loaded EVs (ATP-EVs) were prepared using microfluidic technology, followed by characterization of their morphology (DLS, NTA, SEM, TEM), ATP content, and release rate at 37 °C (pH 7.4). Additionally, the delivery efficacy of ATP-LPs and ATP-EVs was evaluated in vitro on renal cells (HK2 cells) under chemically induced ischemia. The results indicated successful ATP enrichment in EVs, with ATP-EVs showing no significant changes in morphology or size compared to naïve EVs. Notably, ATP-EVs demonstrated superior ATP retention compared to ATP-LPs, protecting the ATP from degradation in the extracellular environment. In an ATP-depleted HK2 cell model, only ATP-EVs effectively restored ATP levels, preserving cell viability and reducing apoptotic gene expression (BCL2-BAX). This study is the first to successfully demonstrate the direct delivery of ATP into renal tubular cells in vitro using EVs as carriers.

Immunomodulatory effects and clinical application of exosomes derived from mesenchymal stem cells

Exosomes (Exos) are extracellular vesicles secreted by cells and serve as crucial mediators of intercellular communication. They play a pivotal role in the pathogenesis and progression of various diseases and offer promising avenues for therapeutic interventions. Exos derived from mesenchymal stem cells (MSCs) have significant immunomodulatory properties. They effectively regulate immune responses by modulating both innate and adaptive immunity. These Exos can inhibit excessive inflammatory responses and promote tissue repair. Moreover, they participate in antigen presentation, which is essential for activating immune responses. The cargo of these Exos, including ligands, proteins, and microRNAs, can suppress T cell activity or enhance the population of immunosuppressive cells to dampen the immune response. By inhibiting lymphocyte proliferation, acting on macrophages, and increasing the population of regulatory T cells, these Exos contribute to maintaining immune and metabolic homeostasis. Furthermore, they can activate immune-related signaling pathways or serve as vehicles to deliver microRNAs and other bioactive substances to target tumor cells, which holds potential for immunotherapy applications. Given the immense therapeutic potential of MSC-derived Exos, this review comprehensively explores their mechanisms of immune regulation and therapeutic applications in areas such as infection control, tumor suppression, and autoimmune disease management. This article aims to provide valuable insights into the mechanisms behind the actions of MSC-derived Exos, offering theoretical references for their future clinical utilization as cell-free drug preparations.

Extracellular vesicles derived from mesenchymal stem cells ameliorate sulfur mustard-induced lung injury by regulating apoptosis via miR-146a-5p

Sulfur mustard (SM) is an extremely toxic chemical warfare agent. Although SM-induced toxicity has long been studied, due to its complexity, the characterization of the precise molecular pathway it targets has been remaining an ongoing area of research. Extracellular vesicles derived from human umbilical cord mesenchymal stem cells (hucMSC-EVs) are natural substances that participate in intercellular communication by delivering microRNA to target cells. Importantly, the microRNA content in EVs can be modified. MiR-146a-5p delivered by EVs were utilized and hucMSCs were further modified with miR-146a-5p mimics or inhibitors to collect EVs that over-(miR-146a-5p+-EVs) or underexpress (miR-146a-5p--EVs) miR-146a-5p. Transcriptome sequencing was used to identify potential mediators of the effects of miR-146a-5p delivered by hucMSC-EVs. Our results showed that hucMSC-EVs reduced SM-induced lung injury by mitigating apoptosis. These effects were enhanced by miR-146a-5p+-EVs and weakened by miR-146a-5p--EVs. Meanwhile, the relationship between apoptosis enhancing nuclease (AEN) and miR-146a-5p was discovered, a novel target of miR-146a-5p. Our study showed that hucMSC-EVs ameliorating sulfur mustard induced lung injury through miR-146a-5p, and AEN was one of the functional molecules in this process.

Therapeutic potential of total flavonoids of Rhizoma Drynariae: inhibiting adipogenesis and promoting osteogenesis via MAPK/HIF-1α pathway in primary osteoporosis

AIM

This study seeks to confirm the therapeutic effectiveness of TRFD in inhibiting adipogenesis and promoting osteogenesis in primary osteoporosis through the MAPK/HIF-1α signaling pathway. C57BL/6J mice underwent ovariectomy (OVX) to induce osteoporosis. Mice were administered TRFD (Low and high doses)estradiol for a duration of 12 weeks. Bone microarchitecture evaluated using Micro-CT, while serum biomarkers and protein expressions were analyzed through enzyme-linked immunosorbent assay, Western blotting, and immunohistochemistry. Furthermore, BMSC were isolated to show differentiation, Osteogenic and adipogenic induction were performed, including ALP activity and Oil Red O staining. Bioinformatics analysis of RNA sequencing data was conducted to identify differentially expressed genes.

RESULTS

Total flavonoids of Rhizoma Drynariae treatment significantly improved bone microarchitecture and reversed histopathological damage in OVX mice. It increased serum levels of osteogenesis markers (RUNX2, BMP-2) and enhanced MAPK and HIF-1α signaling pathways, The results also showed a significant dose, TFDR enhanced the osteogenic differentiation of BMSCs while suppressing adipogenic differentiation, as demonstrated by increased ALP activity and mineralization, alongside, the expression of lipid markers (PPAR-γ, C/EBPα) was inhibited. Furthermore, MAPK/HIF-1α pathway was confirmed be crucial in mediating these effects.

CONCLUSION

TRFD exhibits significant therapeutic potential in treating primary osteoporosis by promoting osteogenesis and inhibiting adipogenesis through the MAPK/HIF-1α pathway. These establish an investigation of TRFD as a natural treatment option for managing osteoporosis.

CLINICAL TRIAL NUMBER

Not applicable.

Human mesenchymal stem cell therapy: Potential advances for reducing cystic fibrosis infection and organ inflammation

Innovation in cystic fibrosis (CF) supportive care, including implementing new antimicrobial agents, improved physiotherapy, and highly effective modulators therapy, has advanced patient survival into the 4th and 5th decades of life. However, even with these remarkable improvements in therapy, CF patients continue to suffer from pulmonary infection and other visceral organ complications associated with long-term deficient cystic fibrosis transmembrane conductance regulator (CFTR) expression. Human mesenchymal stem cells (MSCs) have been utilized in tissue engineering based upon their capacity to provide structural components of mesenchymal tissues. An alternative role of MSCs, however is their versatile utilization as cell-based infusion powerhouses due to the unique capacity to deliver milieu specific soluble biologic factors, promoting immune supportive antimicrobial and anti-inflammatory potency. MSCs derived from umbilical cord blood, bone marrow, adipose and other tissues can be expanded in ex vivo using good manufacturing procedure facilities for a safe, unique therapeutic to reduce and limit CF infection and facilitate the resolution of multi-organ inflammation. In our efforts, we conducted extensive preclinical development and validation of an allogeneic derived bone marrow derived MSC product in preparation for a clinical trial in CF. In this process, potency models were developed to ensure the functional capacity of the MSC product to provide clinical benefit. In vitro, murine in vivo and patient tissue ex vivo potency models were utilized to follow MSC anti-infective and anti-inflammatory potency associated with the CFTR deficient environment. We showed in our "First in CF" clinical trial that the allogeneic MSCs obtained from healthy volunteer bone marrow samples were safe. The advent of improved CF care measures and exciting new small molecules has changed the survival and morbidity phenotype of patients with CF, however, there are CF patients who cannot tolerate or have genotypes that are non-responsive to modulators. Additionally, even with the small molecule therapy, CF patients are living longer, but without genetic correction, with the CF disease manifestation aggravated by the continuance of pre-existing CFTR-associated clinical issues such as ongoing inflammation. MSCs secrete bio-active factors that enhance and protect tissue function and can promote "self-immune" regulation. These properties can provide therapeutic support for the traditional and changing face of CF disease clinical complications. Further, MSC-derived bio-active factors can directly mitigate colonizing pathogens' survival by producing antimicrobial peptides (AMPs) which change the pathogen surface and increase host recognition, elimination, and sensitivity to antibiotics. Herein, we review the potential of MSC therapeutics for treating many facets of CF, emphasizing the potential for providing great additive therapeutics for managing morbidity and quality of life.

Exploring the ncRNA landscape in exosomes: Insights into wound healing mechanisms and therapeutic applications

Exosomal non-coding RNAs (ncRNAs), including miRNAs, lncRNAs, and circRNAs, have emerged as crucial modulators in cellular signaling, influencing wound healing processes. Stem cell-derived exosomes, which serve as vehicles for these ncRNAs, show remarkable therapeutic potential due to their ability to modulate wound healing stages, from initial inflammation to collagen formation. These ncRNAs act as molecular signals, regulating gene expression and protein synthesis necessary for cellular responses in healing. Wound healing is a complex, staged process involving inflammation, hemostasis, fibroblast proliferation, angiogenesis, and tissue remodeling. Stem cell-derived exosomal ncRNAs enhance these stages by reducing excessive inflammation, promoting anti-inflammatory responses, guiding fibroblast and keratinocyte maturation, enhancing vascularization, and ensuring organized collagen deposition. Their molecular cargo, particularly ncRNAs, specifically targets pathways to aid chronic wound repair and support scarless regeneration. This review delves into the unique composition and signaling roles of Stem cell-derived exosomes and ncRNAs, highlighting their impact across wound healing stages and their potential as innovative therapeutics. Understanding the interaction between exosomal ncRNAs and cellular signaling pathways opens new avenues in regenerative medicine, positioning Stem cell-derived exosomes and their ncRNAs as promising molecular-level interventions in wound healing.

Progress of mesenchymal stem cells affecting extracellular matrix metabolism in the treatment of female stress urinary incontinence

Stress urinary incontinence (SUI) is a prevalent pelvic floor dysfunction in women post-pregnancy. Currently, conservative treatment options have low success rates, while surgical interventions often result in multiple complications. The altered state of the extracellular matrix (ECM) is a pivotal factor in the onset of various diseases and likely plays a significant role in the pathogenesis of SUI, particularly through changes in collagen and elastin levels. Recent advances in mesenchymal stem cells (MSCs) therapy have shown considerable promise in treating SUI by modulating ECM remodeling, thereby enhancing the supportive tissues of the female pelvic floor. MSCs exhibit substantial potential in enhancing urethral sphincter function, modulating connective tissue architecture, and stimulating fibroblast activity. They play a pivotal role in the reconstruction and functional recovery of the ECM by influencing various signaling pathways, including TGF-β/SMAD, JAK/STAT, Wnt/β-catenin, PI3K/AKT, and ERK/MAPK. We have reviewed the advancements in MSC-mediated ECM metabolism in SUI and, by integrating the functions of ECM in other diseases and how MSCs can ameliorate conditions through their impact on ECM metabolism, we have projected the future trajectory of SUI treatment development.

Exosomes from adipose-derived stem cells accelerate wound healing by increasing the release of IL-33 from macrophages

BACKGROUND

Mesenchymal stem cell (MSC) -derived exosomes, especially adipose-derived mesenchymal stem cell exosomes (ADSC-Exos), have emerged as a promising alternative for skin damage repair with anti-inflammatory, angiogenic and cell proliferation effects while overcoming some of the limitations of MSC. However, the mechanism by which ADSC-Exos regulates inflammatory cells during wound healing remains unclear. This study investigated how ADSC-Exos regulate macrophages to promote wound healing.

METHODS

ADSC-Exos were isolated using ultracentrifugation, with subsequent quantification of exosomes particle number. To investigate their role in wound healing, the effects of ADSC-Exos on inflammation, angiogenesis, collagen deposition and macrophage polarization were evaluated through immunohistochemical staining, immunofluorescence and western blotting. Changes in gene expression associated with ADSC-Exos-induced macrophage polarization were analyzed using qPCR. RNA sequencing was performed to identify differentially expressed genes affected by ADSC-Exos. The critical role of IL-33 in the wound healing process was further confirmed using Il33-/- mice. Additionally, co-culture experiments were conducted to explore the effects of IL-33 on keratinocyte proliferation, collagen deposition and epithelialization.

RESULTS

ADSC-Exos inhibited the expression of TNF-α and IL-6, induced M2 macrophage polarization, promoted collagen deposition and angiogenesis, and accelerated wound healing. RNA sequencing identified IL-33 as a key mediator in this process. In Il33-/- mice, impaired wound healing and decreased M2 macrophage polarization were observed. The co-culture experiments showed that IL-33 enhanced keratinocyte function through activation of the Wnt/β-catenin signaling pathway. These findings highlight the therapeutic potential of ADSC-Exos in wound healing by modulating IL-33.

CONCLUSIONS

ADSC-Exos promote wound healing by regulating macrophage polarization and enhancing IL-33 release which drives keratinocyte proliferation, collagen deposition and epithelialization via the Wnt/β-catenin signaling pathway. These findings provide a mechanistic basis for the therapeutic potential of ADSC-Exos in tissue repair and regeneration.

Mesenchymal stem cells-derived exosomes attenuate mouse non-heart-beating liver transplantation through Mir-17-5p-regulated Kupffer cell pyroptosis

BACKGROUND

Liver transplantation is the most effective treatment for end-stage liver disease. However, the shortage of donor livers has become a significant obstacle to the advancement of liver transplantation. Mesenchymal stem cells-derived exosomes (MSCs-Exo) have been extensively investigated in liver diseases. However, the underlying mechanisms of how they can protect organ donation after cardiac death (DCD) livers remain unclear.

METHODS

In this study, an arterialized mouse non-heart-beating (NHB) liver transplantation model was used to investigate the effect of MSCs-Exo on NHB liver transplantation. The survival rates, histology, pro-inflammatory cytokine and chemokine expression, and underlying mechanisms were investigated.

RESULTS

The infusion of MSCs-Exo reduced the injury to DCD liver graft tissue. In vitro and in vivo experiments demonstrated that MSCs-Exo could inhibit hydrogen peroxide-induced pyroptosis of Kupffer cells. We found that miR-17-5p was significantly abundant in MSCs-Exo, targeting and regulating the TXNIP expression. This action inhibited NLRP3-mediated pyroptosis of Kupffer cells through the classical Caspase1-dependent pathway, alleviating DCD liver graft injury.

CONCLUSION

Our study elucidated a protective role for MSCs-Exo in a NHB liver transplantation model. This mechanism provides a theoretical basis and new strategies for the clinical application of MSCs-Exo to improve liver graft quality and alleviate the organ shortage in liver transplantation.

Nanoenzyme-Anchored Mitofactories Boost Mitochondrial Transplantation to Restore Locomotor Function after Paralysis Following Spinal Cord Injury

Mitochondrial transplantation is a significant therapeutic approach for addressing mitochondrial dysfunction in patients with spinal cord injury (SCI), yet it is limited by rapid mitochondrial deactivation and low transfer efficiency. Here, high-quality mitochondria microfactories (HQ-Mitofactories) were constructed by anchoring Prussian blue nanoenzymes onto mesenchymal stem cells for effective mitochondrial transplantation to treat paralysis from SCI. Notably, the results demonstrated that HQ-Mitofactories could continuously produce vitality-boosting mitochondria with highly interconnected and elongated network structures under oxidative stress by scavenging excessive ROS. Furthermore, HQ-Mitofactories enabled efficient transfer of therapeutic mitochondria to injured neurons primarily via gap junctions, resulting in the restoration of mitochondrial homeostasis and thereby suppressing intracellular ROS burst and facilitating neuronal repair. After i.v. administration, HQ-Mitofactories migrated to the injured spinal cords of SCI mice and subsequently promoted neuronal regeneration and remyelination. Consequently, HQ-Mitofactory-treated mice successfully recovered locomotor function within 4 weeks, with 40% of the mice fully restoring walking after hindlimb paralysis. Conversely, untreated SCI exhibited completely abolished hindlimb movements. In light of real-time generation of vitality-boosting mitochondria even under oxidative stress and enabling targeted mitochondrial transfer, HQ-Mitofactories have promising therapeutic potential in the context of mitochondrial transplantation to reduce SCI-related paralysis, and more broadly impact the field of neuroregenerative medicine.

Inhibition of Small Extracellular Vesicles by GW4869 Does not Disrupt the Paracrine Regulation of Adipose-Derived Mesenchymal Stem Cells Over Keloid Fibroblasts

BACKGROUND

Keloid, scar caused by atypical wound repair, represents a significant difficulty for specialists in plastic surgery and dermatology. Adipose-derived mesenchymal stem cells (ADSCs) can regulate fibrotic phenotypes of keloid fibroblasts (KFs) in a paracrine fashion, but whether small extracellular vesicles (SEVs) are the key functional carrier in ADSC paracrine regulation of KFs remains unknown. This study aims to explore whether the regulatory effects of conditioned medium (CM) obtained from ADSCs on KFs can be impaired by decreased SEV content in the ADSC-CM.

METHODS

Clinical specimens were utilized to extract keloid fibroblasts (KFs), normal fibroblasts (NFs), and adipose-derived stem cells (ADSCs). Fibroblasts were cultured with CM obtained from ADSCs untreated or treated with the sphingomyelinase inhibitor GW4869. The features of SEVs derived from ADSC-CM were characterized, and fibroblast proliferation, migration, apoptosis, and expression of ECM proteins were analyzed.

RESULTS

The sphingomyelinase inhibitor GW4869 successfully reduced the SEV content in ADSC-CM, and both control ADSC-CM and ADSC-CM with reduced SEV content significantly inhibited KF proliferation, migration, and α-SMA synthesis but not KF apoptosis, whereas only NF proliferation was inhibited by ADSC-CM. The reduced SEV content only affected the inhibition of KF proliferation induced by ADSC-CM.

CONCLUSION

ADSC-CM inhibits various fibrotic phenotypes of KFs, but decreasing the SEV content in ADSC-CM did not significantly alter the antifibrotic effects of ADSC-CM. Thus, SEVs may not be the key mediator of ADSCs paracrine regulation of KFs.

NO LEVEL ASSIGNED

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Human embryonic stem cell-derived immunity-and-matrix-regulatory cells on collagen scaffold effectively treat rat corneal alkali burn

Corneal alkali burns (CAB) are a severe form of ocular injury that often leads to significant vision loss, with limited effective treatment options available beyond corneal transplantation. Immunity and matrix-regulatory cells (IMRCs) have emerged as a promising alternative due to their ability to modulate immune responses and support tissue repair. This study investigates the efficacy of IMRCs on collagen scaffolds (IMRCs-col) for treating CAB in a rat model. We developed a novel treatment combining IMRCs with a collagen scaffold to align with the ocular surface structure. In vitro analyses showed that IMRCs-col significantly upregulated the expression of immune regulatory molecules, including IL-1RA and SCF. Additionally, IMRCs-col effectively inhibited the production of pro-inflammatory cytokines (IL-8 and Gro-a/CXCL1) while promoting pro-regenerative cytokines (bFGF, HGF, and PDGF). In an animal model of CAB, IMRCs-col transplantation demonstrated substantial efficacy in restoring corneal opacity and reducing neovascularization. Histological examination revealed reduced inflammation and improved corneal tissue regeneration compared to untreated CAB. Enhanced activation of pathways associated with anti-inflammatory responses and tissue repair was observed at days 3, 7, and 21 post-treatment.

Hidden Partner of Immunity: Microbiome as an Innovative Companion in Immunotherapy

Recent studies have highlighted that the microbiome is the essential factor that can modulate the clinical activity of immunotherapy. However, the role of the microbiome varies significantly across different immunotherapies, suggesting that it is critical to understand the precise function of the microbiome in each type of immunotherapy. While many previous studies primarily focus on summarizing the role of the microbiome in immune checkpoint inhibitors, we seek to explore a novel aspect of the microbiome in other immunotherapies such as mesenchymal stem cell therapy, chimeric antigen receptor T cell therapy, and antibodies-based therapy (e.g., adalimumab, infliximab, bevacizumab, denosumab, etc.) which are rarely summarized in previous reviews. Moreover, we highlight innovative strategies for utilizing microbiome and microbial metabolites to enhance the clinical response of immunotherapy. Collectively, we believe that our manuscript will provide novel insights and innovative approaches to the researchers, which could drive the development of the next generation of personalized therapeutic interventions using microbiomes.

Static magnetic field contributes to osteogenic differentiation of hPDLSCs through the H19/Wnt/β-catenin axis

BACKGROUND

Static magnetic field (SMF) as an effective physical stimulus is capable of osteogenic differentiation for multiple mesenchymal stem cells, including human periodontal ligament stem cells (hPDLSCs). However, the exact molecular mechanism is still unknown. Therefore, this study intends to excavate molecular mechanisms related to SMF in hPDLSCs using functional experiments.

METHODS

hPDLSCs were treated with different intensities of SMF, H19 lentivirus, and Wnt/β-catenin pathway inhibitor (XAV939). Changes in osteogenic markers (Runx2, Col Ⅰ, and BMP2), Wnt/β-catenin markers (β-catenin and GSK-3β), and calcified nodules were examined using RT-qPCR, western blotting, and alizarin red staining in hPDLSCs.

RESULTS

SMF upregulated the expression of H19, and SMF and overexpressing H19 facilitated the expression of osteogenic markers (Runx2, Col Ⅰ, and BMP2), activation of the Wnt/β-catenin pathway, and mineralized sediment in hPDLSCs. Knockdown of H19 alleviated SMF function, and treatment with XAV939 limited SMF- and H19-mediated osteogenic differentiation of hPDLSCs. Notably, the expression of hsa-miR-532-3p, hsa-miR-370-3p, hsa-miR-18a-5p, and hsa-miR-483-3p in hPDLSCs was regulated by SMF, and may form an endogenous competitive RNA mechanism with H19 and β-catenin.

CONCLUSION

SMF contributes to the osteogenic differentiation of hPDLSCs by mediating the H19/Wnt/β-catenin pathway, and hsa-miR-532-3p, hsa-miR-370-3p, hsa-miR-18a-5p, and hsa-miR-483-3p may be the key factors in it.

Epigenetic modification mediated by PHF20/METTL14/HOXA13 signaling axis modulates osteogenic differentiation of mesenchymal stem cells

This study investigates the mechanism of PHF20 in osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs). BMSCs from Balb/c mouse were cultured and identified through osteogenesis, adipogenesis, and flow cytometry. After osteogenic induction, the levels of OPN and OCN in BMSCs were detected by RT-qPCR. Alizarin red staining and alkaline phosphatase (ALP) staining were used to evaluate the osteogenic differentiation ability of BMSCs. PHF20, METTL14, and HOXA13 expressions were detected by RT-qPCR and Western blot. After quantitative analysis of m6A level, RNA immunoprecipitation (RIP) was performed to measure the enrichment of IGF2BP3 or m6A on HOXA13 mRNA. HOXA13 mRNA stability was assessed after actinomycin D treatment. PHF20, METT14, and HOXA13 expressions gradually increased during osteogenic differentiation of BMSCs. Suppression of PHF20 expression repressed the osteogenic differentiation of BMSCs, mainly resulted in a decrease in OPN and OCN levels, reduced mineralization, and weakened ALP activity. Mechanistically, PHF20 elevated METTL14 expression by enhancing the enrichment of H3K4me3 on its promoter, and METTL14 strengthened HOXA13 m6A methylation to maintain HOXA13 mRNA stability through IGF2BP3. In conclusion, PHF20 elevates METTL14 expression by enhancing H3K4me3 enrichment on its promoter and enhances HOXA13 mRNA stability via IGF2BP3-mediated m6A modification, thus facilitating HOXA13 expression and eventually inducing osteogenic differentiation of BMSCs.

A Comprehensive Review of the Mechanisms and Clinical Development of Monoclonal Antibodies in Cancer Therapy

Cancer is still the disease that ranks first in human mortality in the twenty-first century. In the last 20 years, the concept of molecular targeted therapy has come to the fore with the use of small molecule agents or signal transduction inhibitors that show anticancer effects for certain types of cancer. Monoclonal antibodies, which have a therapeutic effect, especially by providing signal transduction inhibition, are used clinically as first-line treatment in various types of cancer. Molecular targeted therapies are critical for eliminating the adverse effects and drug resistance problems that occur in traditional cancer treatments. This review summarizes current information on various targeted therapeutic agents, including the structure and classification of monoclonal antibodies, their production methods and mechanisms of action, the monoclonal antibodies used in clinical trials, the complement system mechanism and cancer relationship, and the relationship between complement-dependent cytotoxicity and monoclonal antibodies.

Harnessing the ubiquitin proteasome system as a key player in stem cell biology

Intracellular proteins take part in almost every body function; thus, protein homeostasis is of utmost importance. The ubiquitin proteasome system (UPS) has a fundamental role in protein homeostasis. Its main role is to selectively eradicate impaired or misfolded proteins, thus halting any damage that could arise from the accumulation of these malfunctioning proteins. Proteasomes have a critical role in controlling protein homeostasis in all cell types, including stem cells. We will discuss the role of UPS enzymes as well as the 26S proteasome complex in stem cell biology from several angles. First, we shall overview common trends of proteasomal activity and gene expression of different proteasomal subunits and UPS enzymes upon passaging and differentiation of stem cells toward various cell lineages. Second, we shall explore the effect of modulating proteasomal activity in stem cells and navigate through the interrelation between proteasomes' activity and various proteasome-related transcription factors. Third, we will shed light on curated microRNAs and long non-coding RNAs using various bioinformatics tools that might have a possible role in regulating UPS in stem cells and possibly, upon manipulation, can enhance the differentiation process into different lineages and/or delay senescence upon cell passaging. This will help to decipher the role played by individual UPS enzymes and subunits as well as various interrelated molecular mediators in stem cells' maintenance and/or differentiation and open new avenues in stem cell research. This can ultimately provide a leap toward developing novel therapeutic interventions related to proteasome dysregulation.

mir-330-5p from mesenchymal stem cell-derived exosomes targets SETD7 to reduce inflammation in rats with cerebral ischemia-reperfusion injury

This study was to investigate the role of microRNA (miR)-330-5p derived from mesenchymal stem cells-secreted exosomes (MSCs-Exo) in cerebral ischemia-reperfusion injury (CI/RI) through targeting lysine N-methyltransferase SET domain containing 7 (SETD7). MSCs-Exo were separated and identified. MSCs-Exo were used to treat the middle cerebral artery occlusion (MCAO) rat model. By using the nerve injury score, Nissl, hematoxylin and eosin, and terminal deoxynucleotidyl transferase dUTP nick-end labeling staining, the neural function, pathological alterations, and neuronal death in MCAO rats were examined. Using an enzyme-linked immunosorbent test, tumor necrosis factor-α, interleukin (IL)-1β, and IL-6 in brain homogenate were tested. Rat brain expression levels of SETD7 and miR-330-5p were examined. Subsequently, the effects of MSCs-Exo, miR-330-5p, and SETD7 on neurological function and pathological alterations were assessed using gain and loss function tests. miR-330-5p expression was decreased and SETD7 expression was increased in the brain tissue of MCAO rats. Both MSCs-Exo and MSCs-Exo-derived miR-330-5p reduced inflammation in MCAO rats. miR-330-5p targeted SETD7, and SETD7 upregulation blocked the therapeutic effect of MSCs-Exo-derived miR-330-5p on MCAO rats. MSCs-Exo-derived miR-330-5p targets SETD7 to reduce inflammation in MCAO rats, providing a new therapeutic target for CI/RI therapy.

Effects of advanced glycation end products on stem cell

In recent years, stem cell therapy has become a pivotal component of regenerative medicine. Stem cells, characterized by their self-renewal capacity and multidirectional differentiation potential, can be isolated from a variety of biological tissues, including adipose tissue, bone marrow, the umbilical cord, and the placenta. The classic applications of stem cells include human pluripotent stem cells (hPSCs) and mesenchymal stem cells (MSCs). However, numerous factors can influence the normal physiological function of stem cells. For instance, in diabetes mellitus, advanced glycation end products (AGEs) accumulate in the extracellular matrix (ECM), impairing the physiological function of stem cells. These substances are closely associated with aging and the progression of numerous degenerative diseases. AGEs can create an environment that is detrimental to the normal physiological functions of stem cells. By binding to the primary cellular receptor for advanced glycation end products (RAGE), AGEs disrupt the physiological activities of stem cells. The binding of RAGE to various ligands triggers the activation of downstream signaling pathways, contributing to the pathophysiological development of diabetes, aging, neurodegenerative diseases, and cancer. Therefore, there is an urgent need for comprehensive research on the impact of AGEs on stem cells, which could provide new insights into the therapeutic application of stem cells in regenerative medicine.

Effect of cigarette smoke on the proliferation, viability, gene expression, and cellular functions of adipose-derived mesenchymal stem cells from smoking and non-smoking donors

Cigarette smoking negatively impacts mesenchymal stem cell functionality, including proliferation, viability, and differentiation potential. Adipose-derived mesenchymal stem cells (ADMSCs) are increasingly used for therapeutic purposes, but the specific effects of smoking in vivo on these cells are poorly understood. This study investigates the effects of cigarette smoke on the proliferation, viability, gene expression, and cellular functions of ADMSCs from smoking and non-smoking donors. In this study, ADMSCs were isolated from healthy smokers and non-smokers, and cell proliferation was assessed using the MTT assay, viability with apoptosis assays, mitochondrial membrane potential (MMP), and gene expression related to oxidative stress and cellular functions. Cell cycle analysis was also conducted. Our findings reveal a significant decrease in the proliferation of ADMSCs from smokers. Apoptosis assays showed reduced viable cells in smokers without a significant change in MMP, suggesting alternative pathways contributing to decreased viability. Gene expression analysis indicated the upregulation of genes associated with oxidative stress response and cellular defense mechanisms and the downregulation of genes related to inflammatory signaling, detoxification, and cellular metabolism. Cell cycle analysis indicates cycle arrest or delay in smokers, possibly due to stress and potential DNA damage. Smoking negatively affects ADMSCs' proliferation, viability, and function through oxidative stress and gene expression alterations. These findings highlight the importance of considering smoking status in ADMSC therapies and the need for further research to mitigate the effect of smoking on stem cells.

Cell therapy for end-stage liver disease: Current state and clinical challenge

ABSTRACT

Liver disease involves a complex interplay of pathological processes, including inflammation, hepatocyte necrosis, and fibrosis. End-stage liver disease (ESLD), such as liver failure and decompensated cirrhosis, has a high mortality rate, and liver transplantation is the only effective treatment. However, to overcome problems such as the shortage of donor livers and complications related to immunosuppression, there is an urgent need for new treatment strategies that need to be developed for patients with ESLD. For instance, hepatocytes derived from donor livers or stem cells can be engrafted and multiplied in the liver, substituting the host hepatocytes and rebuilding the liver parenchyma. Stem cell therapy, especially mesenchymal stem cell therapy, has been widely proved to restore liver function and alleviate liver injury in patients with severe liver disease, which has contributed to the clinical application of cell therapy. In this review, we discussed the types of cells used to treat ESLD and their therapeutic mechanisms. We also summarized the progress of clinical trials around the world and provided a perspective on cell therapy.

Epigenetic control of dental stem cells: progress and prospects in multidirectional differentiation

Dental stem cells, with their exceptional proliferative capacity and multidirectional differentiation potential, hold significant promise for dental and oral tissue regeneration. Epigenetic inheritance, which involves stable and heritable changes in gene expression and function without alterations to the DNA sequence, plays a critical role in numerous biological processes. Environmental factors are particularly influential in epigenetic inheritance, as variations in exposure can lead to changes in epigenetic modifications that subsequently impact gene expression. Epigenetic mechanisms are widely involved in processes such as bone homeostasis, embryogenesis, stem cell fate determination, and disease development. Recently, the epigenetic regulation of dental stem cells has attracted considerable research attention. This paper reviews studies focused on the epigenetic mechanisms governing the multidirectional differentiation of dental stem cells.

PRRX1 upregulates PD-L1 in human mesenchymal stem cells

Mesenchymal stem cells (MSCs) have been demonstrated to be efficacious in clinical applications for the amelioration of immune disorders, including graft-versus-host disease (GvHD) and Crohn's disease. The immunosuppressive role of Programmed death-ligand 1 (PD-L1) in MSCs is pivotal, yet the regulatory mechanisms governing its expression remain to be fully elucidated. In this study, we explored the influence of paired-related homeobox (PRRX1), a determinant of multipotency and self-renewal in MSCs, on the expression of various surface antigens, notably PD-L1. Multiple isoforms of PRRX1 were found to augment the mRNA levels of MSC markers, such as CD26 and CD317, with all isoforms elevating PD-L1 expression at both mRNA and protein levels. This study reveals that PRRX1 may act as a potential immunomodulatory factor in MSCs by regulating the PD-L1 pathway.

Combination of trimethoprim-sulfamethoxazole and mesenchymal stem cell therapy to treat toxoplasmic encephalitis after hematopoietic stem cell transplantation: A case report

Toxoplasmosis, caused by the parasite Toxoplasma gondii, is a life-threatening infection that may occur following hematopoietic stem cell transplantation (HSCT). Toxoplasmic encephalitis (TE) is one of the most severe manifestations of this infection and often results in unsatisfactory therapeutic outcomes, especially regarding neurological damage. Recent studies have demonstrated that human umbilical cord-derived mesenchymal stem cells (hUC-MSCs) can significantly aid in neural repair and remodeling. Furthermore, hUC-MSCs have been shown to reduce the risk of graft-versus-host disease (GVHD) associated with the reduction or discontinuation of immunosuppressive therapy. In this case report, we present a pediatric patient who developed TE as a complication of haploidentical HSCT. The patient received a combined treatment regimen of standard anti-Toxoplasma therapy and adjunctive hUC-MSC therapy. The outcomes were satisfactory. The patient regained consciousness, maintained a stable body temperature, and regained the ability to perform daily activities independently. Additionally, next-generation sequencing revealed a decrease in Toxoplasma DNA sequences in the blood and cerebrospinal fluid to undetectable levels. This case report underscores the potential of hUC-MSCs as a promising therapeutic modality for TE.

Liuwei Dihuang pills attenuate ovariectomy-induced bone loss by alleviating bone marrow mesenchymal stem cell (BMSC) senescence via the Yes-associated protein (YAP)-autophagy axis

CONTEXT

Liuwei Dihuang pill (LWDH) has been used to treat postmenopausal osteoporosis (PMOP).

OBJECTIVE

To explore the effects and mechanisms of action of LWDH in PMOP.

MATERIALS AND METHODS

Forty-eight female Sprague-Dawley rats were divided into four groups: sham-operated (SHAM), ovariectomized (OVX), LWDH high dose (LWDH-H, 1.6 g/kg/d) and LWDH low dose (LWDH-L, 0.8 g/kg/d); the doses were administered after ovariectomy via gavage for eight weeks. After eight weeks, the bone microarchitecture was evaluated. The effect of LWDH on the differentiation of bone marrow mesenchymal stem cells (BMSCs) was assessed via osteogenesis- and lipogenesis-induced BMSC differentiation. The senescence-related biological indices were also detected using senescence staining, cell cycle analysis, quantitative real-time polymerase chain reaction and western blotting. Finally, the expression levels of autophagy-related proteins and Yes-associated protein (YAP) were evaluated.

RESULTS

LWDH-L and LWDH-H significantly modified OVX-induced bone loss. LWDH promoted osteogenesis and inhibited adipogenesis in OVX-BMSCs. Additionally, LWDH decreased the positive ratio of senescence OVX-BMSCs and improved cell viability, cell cycle, and the mRNA and protein levels of p53 and p21. LWDH upregulated the expression of autophagy-related proteins, LC3, Beclin1 and YAP, in OVX-BMSCs and downregulated the expression of p62.

DISCUSSION AND CONCLUSIONS

LWDH improves osteoporosis by delaying the BMSC senescence through the YAP-autophagy axis.

Injectable decellularized Wharton's jelly hydrogel containing CD56+ umbilical cord mesenchymal stem cell-derived exosomes for meniscus tear healing and cartilage protection

Traditional meniscectomy or suture for meniscal tear usually leads to failed self-healing, cartilage degeneration and worse osteoarthritis. The strategies that facilitate the healing process of torn meniscus and safeguard knee cartilage against degeneration will be promising for clinical therapy. The CD56+ umbilical cord mesenchymal stem cells (UCSCs) (CD56+UCSCs) were sorted from Wharton's jelly using flow cytometer. Then, the modified decellularized Wharton's Jelly hydrogel (DWJH) was combined with isolated CD56+Exos from CD56+UCSCs to fabricate DWJH/CD56+Exos. The in vitro studies were performed to characterize the DWJ (decellularized Wharton's Jelly). The injectability and rheological properties were assessed by shear rate and frequency sweep analysis. The biocompatibility and chondrogenic differentiation inducibility of DWJH/CD56+Exos were performed on human bone marrow mesenchymal stem cells (hBMSCs) and RAW 264.7 cells. The release dynamics was evaluated in vitro and in vivo experiments. As for the in vivo experiments, the operated rats that subjected to a 2 mm full-thickness longitudinal tear in right medial anterior meniscus were injected a single dose of DWJH/CD56+Exos. At 4 and 8 weeks postoperatively, torn meniscus healing and articular cartilage degeneration were evaluated by hematoxylin and eosin (H&E), safranin O/fast green (SO&FG), and Sirius red staining. In in vitro experiments, the injectable DWJH/CD56+Exos demonstrated excellent biocompatibility, exosome releasing efficiency, injectable property and chondrogenic inducibility. The results of in vivo experiments revealed that DWJH/CD56+Exos degraded over time, promoted meniscal chondrogenesis, organized meniscal extracellular matrix remodeling, safeguard articular cartilage and inhibited secondary cartilage degeneration, which accelerated further facilitated torn meniscus healing. The novel injectable DWJH/CD56+Exos promoted meniscal tear healing by promoting meniscal chondrogenesis, safeguarding articular cartilage, and inhibiting secondary cartilage degeneration.

Risperidone accelerates bone loss in mice models of schizophrenia by inhibiting osteoblast autophagy

Background

Risperidone (RIS) is the first-line drug in the clinical treatment of schizophrenia, and long-term use may lead to bone loss and even osteoporosis. This study investigated whether the mechanism of RIS-induced bone loss is related to autophagy.

Methods

The schizophrenia mice were established with the administration of MK-801. Then, RIS were injected, or autophagy inducer rapamycin (RAPA) co-injected for 8 weeks. Cognitive performance was determined by the novel object recognition and Open field tests. Bone loss of schizophrenia mice were assessed using microCT, H&E staining, ALP staining, ARS staining and WB, respectively. Autophagy of schizophrenia mice were detected by immunofluorescence, transmission electron microscopy (TEM) and WB, respectively. In addition, osteogenic differentiation of MC3T3-E1 and BMSCs cells were assessed using H&E staining, ALP staining, ARS staining and WB, respectively.

Results

In the present study, we found that RIS treatment can promote bone loss in schizophrenia mice and inhibit osteogenic differentiation of MC3T3-E1 and BMSCs cells. Interesting, the number of autophagosome and autophagy-related protein expression were decreased after RIS treatment. However, the bone loss and inhibition of osteogenic differentiation induced by RIS in schizophrenia mice were reversed by autophagy inducer RAPA.

Conclusion

RIS significantly increased bone loss and inhibited osteogenic differentiation in schizophrenia mice; the underlying mechanism entails suppressing osteoblast autophagy.

Mesenchymal stem cells alleviate inflammatory responses through regulation of T-cell subsets

Immune-mediated inflammatory disease (IMID) is a complex disorder characterized by excessive immune responses involving T cells and their subsets, leading to direct tissue damage. T cells can be broadly categorized into CD4+ T cells and CD8+ T cells. CD4+ T cells are composed of several subsets, including T helper (Th)1, Th2, Th9, Th17, Th22, follicular helper T cells (Tfhs), and regulatory T cells (Tregs), while effector CD8+ T cells consist mainly of cytotoxic T cells (CTLs). Current therapies for IMID are ineffective, prompting exploration into mesenchymal stem cells (MSCs) as a promising clinical treatment due to their immunomodulatory effects and self-renewal potential. Recent studies have shown that MSCs can suppress T cells through direct cell-to-cell contact or secretion of soluble cytokines. Nevertheless, the precise effects of MSCs on T cell subsets remain inadequately defined. In this review, we summarize the most recent studies that have examined how MSCs modulate one or more effector T-cell subsets and the mechanisms behind these modifications in vitro and several mouse models of clinical inflammation. This also provides theoretical support and novel insights into the efficacy of clinical treatments involving MSCs. However, the efficacy of MSC therapies in clinical models of inflammation varies, showing effective remission in most cases, but also with exacerbation of T-cell-mediated inflammatory damage in some instances.

Proteomic analysis of human Wharton's jelly mesenchymal stem/stromal cells and human amniotic epithelial stem cells: a comparison of therapeutic potential

Perinatal stem cells have prominent applications in cell therapy and regenerative medicine. Among them, human Wharton's jelly mesenchymal stem/stromal cells (hWJMSCs) and human amniotic epithelial stem cells (hAESCs) have been widely used. However, the distinction in the therapeutic potential of hWJMSCs and hAESCs is poorly understood. In this study, we reported the phenotypic differences between these two distinct cell types and provided the first systematic comparison of their therapeutic potential in terms of immunomodulation, extracellular matrix (ECM) remodelling, angiogenesis and antioxidative stress using proteomics. The results revealed that the two cell types presented different protein expression profiles and were both promising candidates for cell therapy. Both types of cells demonstrated angiogenic and antifibrotic potential, whereas hAESCs presented superior immunological tolerance and antioxidant properties, which were supported by a series of relevant in vitro assays. Our study provides clues for the selection of appropriate cell types for diverse indications in cell therapy, which contributes to the advancement of their clinical translation and application.

Behavioral dynamics of medicinal signaling cells from porcine bone marrow in long-term culture

Medicinal signaling cells (MSC) hold promise for regenerative medicine due to their ability to repair damaged tissues. However, their effectiveness can be affected by how long they are cultured in the lab. This study investigated how passage number influences key properties for regenerative medicine of pig bone marrow MSC. The medicinal signiling cells derived from pig bone marrow (BM-MSC) were cultured in D-MEM High Glucose supplemented with 15% foetal bovine serum until the 25th passage and assessed their growth, viability, ability to differentiate into different cell types (plasticity), and cell cycle activity. Our findings showed that while the cells remained viable until the 25th passage, their ability to grow and differentiate declined after the 5th passage. Additionally, cells in later passages spent more time in a resting phase, suggesting reduced activity. In conclusion, the number of passages is a critical factor for maintaining ideal MSC characteristics. From the 9th passage BM-MSC exhibit decline in proliferation, differentiation potential, and cell cycle activity. Given this, it is possible to suggest that the use of 5th passage cells is the most suitable for therapeutic applications.

Unlocking the promise of mesenchymal stem cells and extracorporeal photopheresis to address rejection and graft failure in intestinal transplant recipients

INTRODUCTION

In patients with irreversible intestinal failure, intestinal transplant has become a standard treatment option. Graft failure secondary to acute or chronic cellular rejection continues to be a significant challenge following transplant. Even with optimal immune suppression, some patients continue to struggle with refractory rejection. Both extracorporeal photopheresis (ECP) and extracellular vesicles derived from mesenchymal stem cells (EVs) have been used to treat refractory rejection following intestinal transplantation, although their use remains limited and consistent treatment protocols are lacking.

METHODS

Intestinal transplant recipients who received ECP only or ECP and EVs as rescue therapy for acute cellular rejection or chronic inflammation between 2016 and 2022 were included in this single-center retrospective analysis. Baseline demographics, pre- and post-treatment histopathology, endoscopic and biochemical findings, and long-term transplant outcomes were analyzed.

RESULTS

Three patients (two pediatric and one adult) with acute steroid- and biologic-refractory rejection were treated with ECP and/or EVs, as was one patient (pediatric) with chronic graft rejection and inflammation. Patients received twice weekly ECP for 4 weeks and once weekly thereafter. EVs were administered in three doses each separated by 72 h. Immunosuppression at the time of treatment initiation included high-dose tacrolimus and sirolimus. Histologic resolution of rejection was achieved in all patients over 12-16 weeks. Steroids were weaned to low-dose or withdrawn in every patient within 4 weeks of ECP/EV treatment. C-reactive protein decreased from an average of 14.75 to 1.6 mg/dL post-treatment and fecal calprotectin decreased from average 800 mg/g to 31 mg/g. Donor-induced cytotoxic T cell populations were quantified for two of the patients with acute rejection, and in both cases decreased dramatically following treatment. There were no complications associated with either treatment.

CONCLUSION

Both ECP and EVs present novel opportunities to address graft rejection and inflammation in bowel transplant recipients. More work will be needed to define the optimal therapeutic parameters for each treatment modality.

Exosomes on the development and progression of renal fibrosis

Renal fibrosis is a prevalent pathological alteration that occurs throughout the progression of primary and secondary renal disorders towards end-stage renal disease. As a complex and irreversible pathophysiological phenomenon, it includes a sequence of intricate regulatory processes at the molecular and cellular levels. Exosomes are a distinct category of extracellular vesicles that play a crucial role in facilitating intercellular communication. Multiple pathways are regulated by exosomes produced by various cell types, including tubular epithelial cells and mesenchymal stem cells, in the context of renal fibrosis. Furthermore, research has shown that exosomes present in bodily fluids, including urine and blood, may be indicators of renal fibrosis. However, the regulatory mechanism of exosomes in renal fibrosis has not been fully elucidated. This article reviewed and analysed the various mechanisms by which exosomes regulate renal fibrosis, which may provide new ideas for further study of the pathophysiological process of renal fibrosis and targeted treatment of renal fibrosis with exosomes.

The Therapeutic Potential of Exosomes vs. Matrix-Bound Nanovesicles from Human Umbilical Cord Mesenchymal Stromal Cells in Osteoarthritis Treatment

Osteoarthritis (OA) is a degenerative joint disease with limited therapeutic options, where inflammation plays a critical role in disease progression. Extracellular vesicles (EV) derived from mesenchymal stromal cells (MSC) have shown potential as a therapeutic approach for OA by modulating inflammation and alleviating degenerative processes in the joint. This study evaluated the therapeutic effects for the treatment of OA of two types of EV-exosomes and matrix-bound nanovesicles (MBV)-both derived from the human umbilical cord MSC (UC-MSC) via differential ultracentrifugation. Different phenotypes of human monocyte-derived macrophages (MDM) were used to study the anti-inflammatory properties of EV in vitro, and the medial meniscectomy-induced rat model of knee osteoarthritis (MMx) was used in vivo. The study found that both EV reduced pro-inflammatory cytokines IL-6 and TNF-α in MDM. However, exosomes showed superior results, preserving the extracellular matrix (ECM) of hyaline cartilage, and reducing synovitis more effectively than MBVs. Additionally, exosomes downregulated inflammatory markers (TNF-α, iNOS) and increased Arg-1 expression in macrophages and synovial fibroblasts, indicating a stronger anti-inflammatory effect. These results suggest UC-MSC exosomes as a promising therapeutic option for OA, with the potential for modulating inflammation and promoting joint tissue regeneration.

Mesenchymal Stem Cell-Derived Exosomes: Emerging as a Promising Cell-Free Therapeutic Strategy for Autoimmune Hepatitis

Autoimmune hepatitis (AIH) is an immune-mediated liver disease that currently faces limited treatment options. In its advanced stages, AIH can progress to liver fibrosis and cirrhosis. Recent research has increasingly focused on cell-free therapies, particularly the use of mesenchymal stem cell (MSC)-derived exosomes (Exos), which have shown promise in treating autoimmune diseases, including AIH. MSC-Exos, as microvesicles with low immunogenicity, high safety, and permeability, can deliver RNA, DNA, proteins, lipids, and various drugs for disease treatment, showing promising clinical application prospects. This review provides a comprehensive summary of the current research on MSC-Exos in the treatment of autoimmune hepatitis (AIH) and explores the underlying molecular mechanisms involved. It highlights the significant regulatory effects of MSC-Exos on immune cells and their ability to modify the microenvironment, demonstrating anti-inflammatory and anti-fibrotic properties while promoting liver regeneration. Additionally, this review also discusses potential challenges and future strategies for advancing Exo-based therapies in the treatment of AIH.

Role of hsa-miR-543-KIF5C/CALM3 pathway in neuron differentiation of embryonic mesenchymal stem cells

BACKGROUND

Human umbilical cord mesenchymal stem cells (hUC-MSCs) have the ability to differentiate into nerve cells, which offers promising options for treating neurodegenerative diseases.

AIM

To explore the important regulatory molecules of hUC-MSCs differentiation into neurons.

METHOD

In this research, the neural differentiation of hUC-MSCs was induced by a low-serum DMSO/BHA/DMEM medium. The GEO database was used to retrieve the relevant datasets. The starBase and miEAA databases were used for bioinformatics analysis. RT-qPCR was used to detect the hsa-miR-543 level and the mRNA levels of NSE, NeuN, NF-M, KIF5C, and CALM3. The protein levels of KIF5C and CALM3 were checked by western blotting.

RESULTS

The expression levels of NSE, NeuN, NF-M, KIF5C, and CALM3 were elevated, while hsa-miR-543 was under-expressed in neuro-induced hUC-MSCs. The increase in NSE, NeuN, and NF-M mRNA levels induced by DMSO/BHA/DMEM was partially reversed by the knockdown of KIF5C and CALM3 in hUC-MSCs. Moreover, the transfection of hsa-miR-543 mimic partially countered the DMSO/BHA/DMEM-induced elevation in NSE, NeuN, NF-M, KIF5C, and CALM3 mRNA levels.

CONCLUSION

KIF5C and CALM3 facilitated the neuronal differentiation of hUC-MSCs, whereas hsa-miR-543 exerted an opposing effect by negatively regulating KIF5C and CALM3.

Autologous Bone Marrow-Derived Mesenchymal Stem Cells in the Reversal of Unobstructed Azoospermia in Rats

Background and Objective

Non-obstructive azoospermia (NOA) is an important cause of male infertility. This study is being proposed to assess the efficacy of autologous bone marrow-derived mesenchymal stem cells (MSCs) in the reversal of busulfan-induced NOA in rats.

Methods

Twenty adult 3-month-old male rats were divided into two groups: a control group and a study group. In the study group, bone marrow was aspirated to culture MSCs. NOA was created by stopping endogenous spermatogenesis in all the animals by injecting two doses of busulfan 10 mg/kg body weight with a 3 week interval. Four weeks after the last dose of busulfan, two animals were euthanized and the testes were studied histologically to confirm complete azoospermia. In the study group, five million MSCs in 1 mL normal saline were injected into seminiferous tubules; and in the control group, 1 mL of normal saline was injected. After 4 weeks of MSC injection, all the rats were euthanized and epididymis tails and testes were harvested and sent for measurement of serological indices, including luminal, cellular, and total diameters, luminal, cellular, and cross-sectional areas, number of tubules per unit area of testis, numerical density of the tubules, and spermatogenesis index, pre- and post-MSC transplantation.

Results

The effect of busulfan on the testicular tissue was universally devastating. In the control group, there was variable length and width of markedly necrotic seminiferous tubules, whereas in the group treated with autologous bone marrow-derived MSCs there was variable height of germinal epithelium in seminiferous tubules, with active spermatogenesis, showing spermatogonia, spermatocytes, and sperm.

Conclusion

MSC injection in the testis has the potential to reverse the testicular function of spermatogenesis after cytotoxic therapy. Human trials should be undertaken to confirm our findings and bring the results into clinical practice.