Stem Cells Translational Medicine最新文献

Given the high heterogeneity of type 2 diabetes mellitus (T2DM), it is imperative to develop personalized stem cell infusion regimen for targeted metabolic phenotype in order to ensure optimal therapeutic efficacy. In this study, we conducted a comparative analysis of 4 infusion regimens involving single and repeated infusions of human umbilical cord Wharton's jelly-derived MSCs (hucMSCs), single infusions of umbilical cord blood mononuclear cells (UCB), and sequential infusions of hucMSCs and UCB in T2DM rats. Results showed all 4 infusion regimens exhibited comparable efficacy in lowering fasting blood glucose levels and suppressing glucagon secretion. Single and double infusions of hucMSCs exhibited a tendency to migrate to the liver, thereby better at ameliorating hepatic glucose metabolism by enhancing glycogen synthesis and storage, promoting glycolysis, inhibiting gluconeogenesis, and improving insulin signal transduction. The sequential infusion of hucMSCs and UCB demonstrated specific cell tropism toward the pancreas, leading to prolonged glucose-lowering effects following a glucose tolerance test, restoration of early-phase insulin secretion, stimulation of islet beta cell proliferation and improvement in the beta/alpha ratio. Multiple injections, regardless of cell type, reduced the expression of systemic chronic inflammatory markers such as IL-1β, IL-6, IL-17, IL-22, and IFN-γ. Finally, a single dose of UCB exhibited a greater tendency to target visceral fat and enhanced effectiveness in regulating levels of total cholesterol and triglycerides. In conclusion, our study provided personalized stem cell regimens for diverse T2DM metabolic phenotypes, thereby offering improved treatment alternatives for future clinical trials and applications.

Background: Cervical cancer is often caused by persistent high-risk human papillomavirus (HPV) infection, causing precancerous lesions. Human umbilical cord mesenchymal stem cells-derived small extracellular vesicles (hucMSC-sEV) exhibit diverse effects on tumors. This study investigates hucMSC-sEV, the impact and mechanisms on HPV-positive cervical precancerous lesion cells to provide new treatment insights.

Materials and methods: We previously obtained hucMSC and hucMSC-sEV. In vitro experiments evaluated hucMSC-sEV effects on the proliferation and migration of S12 cells (derived from cervical precancerous lesions). Bioinformatics identified key microRNA components, and their impact on S12 cell proliferation and migration was investigated. The target gene of the microRNA component was predicted and confirmed via bioinformatics and dual-luciferase reporter assays. Lentiviral systems overexpressed target gene in S12 cells to examine the effects on microRNA impacts. SH-42 inhibitor was used to investigate target gene treatment potential. Immunohistochemistry assessed target gene expression in cervical precancerous lesions tissue.

Results: hucMSC-sEV significantly inhibited S12 cell proliferation and migration. Bioinformatics identified miR-370-3p as an effective cargo, which also suppressed S12 cell proliferation and migration. miR-370-3p was confirmed targeting DHCR24 (24-Dehydrocholesterol Reductase). DHCR24 overexpression reversed miR-370-3p's inhibitory effects, while SH-42 counteracted DHCR24 overexpression's promoting effects. Clinical specimen analysis supported these findings, demonstrating a positive correlation between DHCR24 protein expression and cervical precancerous lesions' progression.

Conclusions: hucMSC-sEV inhibits S12 cell proliferation and migration, mediated by miR-370-3p targeting DHCR24 to regulate cellular cholesterol content. DHCR24 inhibition reduces the cholesterol level and cell functions, suggesting its potential as a therapeutic target in cervical precancerous lesions.

Mesenchymal stem cells (MSCs) are multipotent cells with high self-renewal and multilineage differentiation abilities, playing an important role in tissue healing. Recent advancements in stem cell-based technologies have offered new and promising therapeutic options in regenerative medicine. Upon tissue damage, MSCs are immediately mobilized from the bone marrow and move to the injury site via blood circulation. Notably, allogenically transplanted MSCs can also home to the damaged tissue site. Therefore, MSCs hold great therapeutic potential for curing various diseases. However, one major obstacle to this approach is attracting MSCs specifically to the injury site following systemic administration. In this review, we describe the molecular pathways governing the homing mechanism of MSCs and various strategies for improving this process, including targeted stem cell administration, target tissue modification, in vitro priming, cell surface engineering, genetic modifications, and magnetic guidance. These strategies are crucial for directing MSCs precisely to the injury site and, consequently, enhancing their migration and local tissue repair properties. Specifically, our review provides a guide to improving the therapeutic efficacy of clinical applications of MSCs through optimized in vivo administration and homing capacities.

Ultraviolet (UV) radiation is the primary extrinsic factor in skin aging, contributing to skin photoaging, actinic keratosis (AK), and even squamous cell carcinoma (SCC). Currently, the beneficial role of mesenchymal stromal cell-derived small extracellular vesicles (MSC-sEVs) in cutaneous wound healing has been widely reported, but the field of photoaging remains to be explored. Our results suggested that human umbilical cord MSC-derived sEVs (hucMSC-sEVs) intervention could effectively alleviate skin photoaging phenotypes in vivo and in vitro, including ameliorating UV-induced histopathological changes in the skin and inhibiting oxidative stress and collagen degradation in dermal fibroblasts (DFs). Mechanistically, pretreatment with hucMSC-sEVs reversed UVA-induced down-regulation of pregnancy zone protein (PZP) in DFs, and achieved photoprotection by inhibiting matrix metalloproteinase-1 (MMP-1) expression and reducing DNA damage. Clinically, a significant decrease in PZP in AK and SCC in situ samples was observed, while a rebound appeared in the invasive SCC samples. Collectively, our findings reveal the effective role of hucMSC-sEVs in regulating PZP to combat photoaging and provide new pre-clinical evidence for the potential development of hucMSC-sEVs as an effective skin photoprotective agent.

Hypoxic-ischemic encephalopathy (HIE), associated with high mortality and neurological sequelae, lacks established treatment except therapeutic hypothermia. Clinical-grade multilineage-differentiating stress-enduring (Muse) cells (CL2020) demonstrated safety and efficacy in nonclinical HIE rat models, thereby leading to an investigator-initiated clinical trial to evaluate CL2020 safety and tolerability in neonatal HIE as a single-center open-label dose-escalation study with 9 neonates with moderate-to-severe HIE who received therapeutic hypothermia. Each patient received a single intravenous injection of CL2020 cells between 5 and 14 days of age. The low-dose (3 patients) and high-dose (6 patients) groups received 1.5 × 106 and 1.5 × 107 cells/dose, respectively. The occurrence of any adverse event within 12 weeks following CL2020 administration was the primary endpoint of this trial. No significant changes in physiological signs including heart rate, blood pressure, and oxygen saturation were observed during or after administration. The only adverse event that may be related to cell administration was a mild γ-glutamyltransferase level elevation in one neonate, which spontaneously resolved without any treatment. All patients enrolled in the trial survived, and normal developmental quotients (≥ 85) in all 3 domains of the Kyoto Scale of Psychological Development 2001 were observed in 67% of the patients in this trial. CL2020 administration was demonstrated to be safe and tolerable for neonates with HIE. Considering the small number of patients, a randomized controlled confirmatory study is warranted to verify these preliminary findings and evaluate the efficacy of this therapy.

Preemptive regenerative medicine using mesenchymal stem cells (MSCs) may provide a novel therapeutic approach to prevent the progression from organ damage to organ failure. Although immunosuppressive drugs are often used in patients with organ disorder, their impact on MSC therapy remains unclear. We investigated the effects of immunosuppressive drugs on the therapeutic efficacy of MSCs. We created unilateral ureteral obstruction models, as a well-established model of renal fibrosis, a preliminary stage of organ failure. Three immunosuppressive drugs (methylprednisolone, cyclosporine, and cyclophosphamide) were intraperitoneally administered 3 days after surgery, and MSCs were injected via tail vein the following day. Preadministration of methylprednisolone or cyclophosphamide interfered with MSC activation by reducing expression of interferon-gamma (IFN-γ) and high-mobility group box-1 protein, thus significantly attenuating the therapeutic efficacy of MSCs. Preadministration of cyclophosphamide downregulated the expression of stromal cell-derived factor-1/C-X-C motif ligand 12, which is a potent migration factor for MSCs, resulting in reduced MSC engraftment in the renal cortex. IFN-γ-preconditioned activated MSCs were unaffected by these drugs and maintained their beneficial therapeutic effects. Cyclosporine preadministration had no effect on the therapeutic efficacy of MSCs. Our study demonstrated that the administration of certain immunosuppressive drugs interfered with MSC activation and engraftment at the site of injury, resulting in a significant attenuation of their therapeutic efficacy. These findings provide crucial information for selecting patients suitable for MSC therapy. Use of MSCs preactivated with IFN-γ or other means is preferred for patients on methylprednisolone or cyclophosphamide.

Cerebral organoids (COs) in cell replacement therapy offer a viable approach to reconstructing neural circuits for individuals suffering from stroke or traumatic brain injuries. Successful transplantation relies on effective engraftment and neurite extension from the grafts. Earlier research has validated the effectiveness of delaying the transplantation procedure by 1 week. Here, we hypothesized that brain tissues 1 week following a traumatic brain injury possess a more favorable environment for cell transplantation when compared to immediately after injury. We performed a transcriptomic comparison to differentiate gene expression between these 2 temporal states. In controlled in vitro conditions, recombinant human progranulin (rhPGRN) bolstered the survival rate of dissociated neurons sourced from human induced pluripotent stem cell-derived COs (hiPSC-COs) under conditions of enhanced oxidative stress. This increase in viability was attributable to a reduction in apoptosis via Akt phosphorylation. In addition, rhPGRN pretreatment before in vivo transplantation experiments augmented the engraftment efficiency of hiPSC-COs considerably and facilitated neurite elongation along the host brain's corticospinal tracts. Subsequent histological assessments at 3 months post-transplantation revealed an elevated presence of graft-derived subcerebral projection neurons-crucial elements for reconstituting neural circuits-in the rhPGRN-treated group. These outcomes highlight the potential of PGRN as a neurotrophic factor suitable for incorporation into hiPSC-CO-based cell therapies.

Stem cell transplantation offers a promising therapy that can be administered days, weeks, or months after a stroke. We recognize 2 major mitigating factors that remain unresolved in cell therapy for stroke, notably: (1) well-defined donor stem cells and (2) mechanism of action. To this end, we advance the use of ProtheraCytes, a population of non-adherent CD34+ cells derived from human peripheral blood and umbilical cord blood, which have been processed under good manufacturing practice, with testing completed in a phase 2 clinical trial in post-acute myocardial infarction (NCT02669810). We also reveal a novel mechanism whereby ProtheraCytes secrete growth factors and extracellular vesicles (EVs) that are associated with angiogenesis and vasculogenesis. Our recent data revealed that intranasal transplantation of ProtheraCytes at 3 days after experimentally induced stroke in adult rats reduced stroke-induced behavioral deficits and histological damage up to 28 days post-stroke. Moreover, we detected upregulation of human CD63+ EVs in the ischemic brains of stroke animals that were transplanted with ProtheraCytes, which correlated with increased levels of DCX-labeled neurogenesis and VEGFR1-associated angiogenesis and vasculogenesis, as well as reduced Iba1-marked inflammation. Altogether, these findings overcome key laboratory-to-clinic translational hurdles, namely the identification of well-characterized, clinical grade ProtheraCytes and the elucidation of a potential CD63+ EV-mediated regenerative mechanism of action. We envision that additional translational studies will guide the development of clinical trials for intranasal ProtheraCytes allografts in stroke patients, with CD63 serving as a critical biomarker.

Eukaryotic translation initiation factor 6 (eIF6) plays a crucial role in 60S ribosome biogenesis and protein translation, as well as in hypertrophic scar formation, but its potential role in epithelialization is still poorly understood. Herein, we found that eIF6 negatively correlated with the wound healing process. Mice with genetically knockdown eIF6 (eIF6+/-) showed faster re-epithelization as shown by the longer tongue of the newly formed epidermis. Furthermore, eIF6 ablation accelerated the wound healing process by targeting basal keratinocytes in the eIF6 keratinocyte-conditional knockout (eIF6f/+; Krt5-Cre+) mice. Mechanistically, keratin 6B, an important wound-activated protein, was significantly upregulated in eIF6f/+; Krt5-Cre+ mice skin as proved by RNA-seq, western immunoblots, and immunofluorescence staining. Moreover, an elevated level of KRT6B and accelerated proliferative capacity were also observed in stable knockdown eIF6 HaCaT cells. Taken together, eIF6 downregulation could accelerate epithelialization by upregulating KRT6B expression and promoting keratinocyte proliferation. Our results for the first time indicate that eIF6 might be a novel target to regulate re-epithelialization.

Background: Infusion of mesenchymal stem cells (MSCs) via portal vein is one of the main ways for MSCs transplantation to treat liver cirrhosis (LC). As the tissue of LC showed diffuse fibrosis and thickened Glission sheath, the soft pig-tail catheter, or central venous catheter can not successfully insert the portal vein. Thus, our study used an improved method and performed a relatively comprehensive system to evaluate the effect for human umbilical cord-derived mesenchymal stem cells (hUC-MSCs) transplantation.

Method: Fifteen patients with hepatitis B-related cirrhosis were enrolled in the study, and we performed hUC-MSCs transplantation via portal vein by using an 16-G needle and 0.035-inch guide wire combined with 7FR "retentional metal stiffner trocar" of pig-tail catheter under the guidance of contrast-enhanced ultrasound. Serum liver function, fibrotic indicators, tissue stiffness, coagulation function, and hemodynamics were measured at weeks 4, 12, and 24 after MSCs transplantation. Liver biopsy was performed before and 24 weeks after hUC-MSCs transplantation.

Result: After hUC-MSCs transplantation, the prothrombin time was lower than before. The levels of hyaluronic acid and IV-C(Type IV collagen) in fibrotic indicators were significantly reduced, and the Young's modulus was also decreased. Moreover, liver biopsy showed that the lytic necrosis of hepatocyte was decreased. In liver hemodynamics, the portal vein diameter was decreased after hUC-MSCs transplantation.

Conclusion: hUC-MSCs transplantation can alleviate liver damage caused by LC. The improved "retentional metal stiffner trocar" of pig-tail catheter was safe and effective in the infusion of hUC-MSCs transplantation, which is worth promoting in clinical practice.