Stem Cells International最新文献

Background: Bronchopulmonary dysplasia (BPD) remains a significant challenge in the management of preterm infants. Although conventional treatment approaches have helped reduce the morbidity associated with BPD, the prevalence of the condition has not decreased, highlighting an urgent need for new therapies. Mesenchymal stromal cell (MSC) therapy has emerged as a potentially promising intervention, showing a favorable safety profile in Phase II clinical trials. However, research on the use of MSCs as a late-term therapeutic strategy for established BPD is still in its early stages, indicating a need for further studies to evaluate their effectiveness and optimal application.

Aim: To investigate the results of seven extremely preterm infants who underwent an MSC therapy for severe established BPD.

Method: A cohort of seven infants diagnosed with severe BPD (sBPD) received MSC therapy to assist in their transition to spontaneous breathing. For the first six infants, MSC therapy was discontinued after extubation; however, the final infant continued to receive MSC therapy as he remained on nasal continuous positive airway pressure (nCPAP).Each treatment cycle involved administering 1 million MSCs per kilogram via intratracheal injection, along with an additional 0.5 million MSCs delivered through intravenous infusion. Treatment was initiated between postnatal days 32 and 84. The first three infants each underwent two treatment cycles, the fourth infant received three cycles, and the last three infants were scheduled for 4 weekly cycles. A retrospective analysis was conducted to evaluate the outcomes of the therapy.

Results: All infants were successfully extubated to nCPAP following MSC treatment. However, two infants who underwent two cycles of MSC therapy could not be weaned off respiratory support. In contrast, all infants who received three to four cycles were successfully weaned off the ventilators and discharged home without the need for supplemental oxygen. Additionally, secondary benefits were observed, including improvements in intraventricular hemorrhage (IVH) and retinopathy of prematurity (ROP), a decrease in the number of packed red blood cell transfusions, and fewer episodes of sepsis.

Conclusions: Our findings indicate that administering up to four treatment cycles may be more effective for the long-term management of sBPD. Additionally, using MSCs through both intratracheal and intravenous routes could offer benefits beyond just the lungs, highlighting an area for further research.

Background: Adipose-derived mesenchymal stem cells (ADSCs) have great potential in the realm of tissue repair and regenerative medicine. However, the exact effects of ADSCs on the healing of skin wounds and the underlying mechanisms remain unexplored. Here, we investigated the effects of ADSCs on fibroblasts and keratinocytes and their related molecular mechanisms in wound healing.

Methods: We used a murine model in vivo and a Transwell coculture system in vitro. The proliferation and migration abilities of human dermal fibroblasts (HDFs) and human immortalized keratinocytes (HaCaT) were analyzed after coculture with ADSCs, and the target molecules were investigated by transcriptome sequencing. We further investigated phenotypic changes by knocking down and overexpressing the target molecule and analyzed the potential mechanisms.

Results: We successfully extracted, expanded, and identified ADSCs. ADSCs not only accelerated wound healing in mice but also improved healing quality. Coculture with ADSCs augmented the proliferation and migration capacities of main skin cells in vitro. RNA sequencing analysis revealed that the level of serpin family E member 1 (SERPINE1) in both HDF and HaCaT was significantly regulated by ADSCs. Knockdown of SERPINE1 restrained the proliferation and migration phenotypes of HDF and HaCaT, while overexpression of SERPINE1 did exactly the opposite. Pathway enrichment analysis revealed that SERPINE1 was mainly related to PI3K-Akt and MAPK signaling pathways.

Conclusion: The in vivo model and in vitro cell test demonstrate that ADSC effectively promotes cutaneous wound healing by augmenting the proliferation and migration of fibroblasts and keratinocytes through upregulating SERPINE1, which provides novel insights into the biological roles of SERPINE1 in wound healing and suggests ADSC has a promising future in skin injury therapy.

Limbal stem cell deficiency (LSCD) results from the loss or dysfunction of limbal stem cells, posing a significant challenge due to limited treatment options. Autologous oral mucosal epithelial cell (OMEC) sheet transplantation is an innovative therapy, but its effectiveness in smokers remains unclear. This study aims to investigate the impact of smoking on the efficacy of autologous OMEC sheet transplantation for LSCD and explores how acrolein, a major cigarette smoke component, affects the biological properties of these cells. This retrospective cohort study included 13 LSCD patients (13 eyes), divided into never smokers (seven eyes) and smokers (six eyes), all of whom received autologous OMEC sheet transplantation. The study compared colony-forming abilities and sheet thickness between the groups, assessed corneal epithelial repair postoperatively, and conducted in vitro experiments treating human OMECs (hOMECs) with acrolein. Evaluations focused on colony-forming ability, stem cell marker protein P63 expression, and the secretion of repair factors (transforming growth factor-beta [TGF-β], basic fibroblast growth factor [bFGF], and hepatocyte growth factor [HGF]) as well as the wound healing potential in human corneal epithelial cells. Postoperative results showed significant improvements in corneal epithelial defects, neovascularization, and best visual acuity in never smokers. However, adhesions recurred in both groups, with earlier recurrence in smokers. In vitro, acrolein significantly inhibited the proliferation of OMECs, reduced P63 expression, and decreased the secretion of TGF-β and HGF, though bFGF levels remained unchanged, impairing wound healing in scratched corneal epithelial cells. Smoking adversely affects the efficacy of autologous OMEC transplantation for LSCD, with acrolein as a potential key factor. Future research should focus on understanding the mechanisms by which smoking impacts OMECs and developing improved therapeutic strategies for smokers with LSCD. Trial Registration: ClinicalTrials.gov identifier: NCT03015779.

Background: Severe osteonecrosis of the femoral head (ONFH) secondary to corticosteroid therapy in symptomatic, hematological young patients currently has no therapeutic alternative, and early total hip replacement (THR) is a high-risk intervention in those patients.

Objectives: To evaluate feasibility, safety, and early efficacy of allogeneic expanded mesenchymal stromal cells (MSCs) in a pilot clinical trial.

Methods: Pilot phase 1 open, noncontrolled, nonrandomized clinical trial evaluating the bone regeneration capacity in seven hips from four patients (young females 11-19 year old) with symptomatic, severe bilateral femoral head osteonecrosis (secondary to corticosteroid therapy), 1 year after being surgically treated with 140 × 10⁶ allogenic MSC plus forage.

Results: The proposed therapy proved feasibility, safety at 1 and 4 years (no related serious adverse events [SAEs]), and early efficacy (nonsignificant) in the case analysis (5/7 hips avoiding THR at 4 years).

Conclusions: The implantation of expanded allogeneic MSC in young patients to prevent conversion to a THR or collapse of the femoral head due to severe osteonecrosis is feasible without safety concerns in the longer-term follow-up (FU) upto 4 years. Trial Registration: EudraCT number: 2018-000886-35.

Background: Mesenchymal stromal cells (MSCs) support tissue repair in osteoarthritis (OA), with migration to damaged tissue being a key strategy in in situ tissue engineering. Their regenerative potential depends on factors such as differentiation, level of senescence, and responsiveness to signaling molecules. However, previous findings on these properties of OA MSCs remain inconclusive. This study integrates multiple aspects and tests feasibility using a well-characterized chemoattractant.

Methods and results: MSCs from non-OA donor (ND) and OA donor were characterized for their trilineage differentiation potential as well as for their senescence level by (immune-) histochemistry, RT-qPCR, microarray analysis, and a bead-based immunoassay for cell culture supernatants. No difference in differentiation and senescence level was observed, the latter being indicated by a similar activity of β-Galactosidase (β-gal), gene expression profiles of cyclin-dependent kinase (CDKN) inhibitor 2A (CDKN2A), CDKN inhibitor 1A (CDKN1A), sirtuin 1 (SIRT1), and matrix metallopeptidase 1 (MMP1), as well as secreted cytokines. Chemokine receptors in OA MSCs were detected using immunohistochemistry and RT-qPCR. Expression of CCR1-CCR7, CCR9, and CXCR1-CXCR6 in OA MSCs was confirmed on gene and protein levels. Both OA and ND MSCs migrated toward 1000 nM CCL25, as evaluated via a Boyden chamber assay. Subsequent genome-wide microarray analysis of OA MSCs after treatment with 1000 nM CCL25 corroborated its influence on migration, proliferation, apoptosis, and differentiation as defined by Gene Ontology terms (GO terms). Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis confirmed this broad impact and emphasized the role of cytokine-cytokine-receptor interaction and metabolic pathways.

Conclusion: Our data indicate that OA MSCs retain their differentiation potential and do not exhibit an increased senescent phenotype. Their chemokine receptor profile is conducive of migration, and both OA and ND MSCs respond to CCL25, highlighting the potential of OA MSCs for directed in situ repair.

Human dental pulp stem cells (hDPSCs) hold significant promise for bone regeneration, yet efficient osteogenic induction remains challenging. Phosphorylated oligosaccharides of calcium (POs-Ca), a novel calcium salt derived from potato starch, has recently attracted attention for its remineralization capabilities and potential to promote stem cell differentiation. Here, we investigated the impact of POs-Ca on the osteogenic differentiation of hDPSCs and its underlying mechanism. Isolated hDPSCs were characterized via flow cytometry based on mesenchymal surface markers. Biocompatibility and osteogenic differentiation were assessed via Cell Counting Kit-8 (CCK-8) assay, alkaline phosphatase (ALP) activity, Alizarin Red S staining, and protein levels of osteogenic (Collagen I, DSPP, DMP1, and RUNX2). Intracellular Ca²⁺ flux was monitored using Fluo-4 AM, while AMP-activated protein kinase (AMPK) signaling and autophagic flux were analyzed by western blot (p-AMPK, p-ULK1, and light chain 3 (LC3)-II), TEM, and LC3-GFP imaging. Mechanistic studies employed verapamil (Ca²⁺ channel blocker), Compound C (CC;AMPK inhibitor), and chloroquine (CQ;autophagy inhibitor). POs-Ca (5 mg/mL) exhibited excellent biocompatibility and significantly promoted osteogenic differentiation, as evidenced by a 3.22-fold increase in ALP activity and markedly enhanced mineralized nodule formation as shown by Alizarin Red S staining. Mechanistic studies revealed that POs-Ca triggers rapid intracellular Ca²⁺ influx, activating the AMPK pathway and inducing autophagic flux. Pharmacological inhibition established the essential causality of this cascade: verapamil abolished osteogenic enhancement, while CC and CQ suppressed ALP activity, mineralization, and osteogenic marker expression. Notably, CQ reciprocally attenuated POs-Ca-induced Ca²⁺ influx, revealing novel bidirectional Ca²⁺-autophagy crosstalk. In conclusion, POs-Ca might promote hDPSCs osteogenesis via a calcium influx-driven AMPK-autophagy axis, providing a foundation for novel biomaterials that exploit physiological calcium signaling. These findings offer immediate translational potential for developing minimally invasive, cost-effective strategies in dental pulp regeneration and bone defect repair.

Human umbilical cord-derived mesenchymal stem cells (hUC-MSCs) ameliorate motor deficits in cerebral palsy (CP), but the effect of injection frequency remains unclear. Moreover, most studies have focused on mild CP models (unilateral carotid artery occlusion [UCAO] model). This study explored the effect and mechanism of hUC-MSCs in a rat model of moderate-to-severe CP (bilateral carotid artery occlusion [BCAO] model). On postnatal Day 4 (P4), Wistar rat pups underwent BCAO induction. Subsequently, they received either a single intrathecal injection of hUC-MSCs on P21 or repeated injections on P21, P28, P35, and P42. Motor performance was assessed using the rotarod and front-limb suspension tests, while neuronal regeneration and inflammation were evaluated via biomarkers including neuronal nuclear antigen (NeuN), ionized calcium-binding adapter molecule-1 (Iba-1), glial fibrillary acidic protein (GFAP), myelin basic protein (MBP), and brain-derived neurotrophic factor (BDNF). P18 model screening confirmed that the BCAO model resulted in more severe brain damage and motor impairment than the UCAO model. After injection of lentivirally transfected hUC-MSCs, it was found that hUC-MSCs could nest in the damaged area and survive for at least 3 days. Administration of hUC-MSCs following BCAO modeling led to notable improvements in both behavioral performance and histological outcomes. Furthermore, repeated injections offered greater therapeutic benefits compared to single injection. It indicated that the efficacy of repeated injections of hUC-MSCs in the treatment of moderate-to-severe CP was superior to that of single injection. Its mechanism was related to the improvement of damaged myelin structure, reduced immunoinflammatory responses, and increased neurotrophic support.

Globally, stroke stands as a principal cause of death and disability, presenting formidable challenges in rehabilitation. Conventional therapeutic modalities often fail to restore functional capabilities fully, underscoring the need for innovative treatment strategies. Stem cell therapy emerges as a revolutionary approach, capitalizing on the regenerative capabilities of stem cells to improve neurological function poststroke. This review evaluates the roles of various stem cell types-mesenchymal stem cells (MSCs), neural stem cells (NSCs), and induced pluripotent stem cells (iPSCs)-in the realm of stroke recovery. It elucidates their distinct biological mechanisms, evaluates their therapeutic impact based on clinical trial data, and discusses their efficacy in fostering neural repair and recovery. MSCs are particularly noted for their role in immunomodulation and promotion of angiogenesis and neurogenesis, with clinical evidence supporting their safety and effectiveness in stroke recovery. NSCs are lauded for their ability to differentiate into diverse neural lineages. They integrate into neural circuits to enhance synaptic connectivity and neuroplasticity. iPSCs, known for their versatility, can be tailored to patient-specific needs and are shown in preclinical settings to reduce infarct size and promote the survival of neuronal cells. However, the field grapples with challenges, including optimizing stem cell transplantation timing, precision in cell delivery, integration efficiency, and immune system compatibility. These issues call for harmonization of methodologies across ongoing studies to ensure the reliability and consistency of therapeutic outcomes. This review highlights the promising future and challenges of stem cell therapy for treatment of stroke.

Repair of large soft tissue defects by tissue expansion often faces difficulties in skin expansion. Particularly in those who have lost a significant amount of skin and subcutaneous tissue due to total mastectomy, tissue expansion may result in skin breakdown and exposure of the expander. Subcutaneous fat construction by autologous fat grafting before expansion seems to assist skin expansion. We hypothesize that it may be related to the adipose-derived stem cells (ADSCs) in subcutaneous fat. In this study, we confirmed this phenomenon through animal experiments and provided a preliminary investigation of the possible mechanisms involved. Four groups were designed for the experiment, experimental group (EG) for autologous fat flap transfer and tissue expansion. Fat grafting control group (FGCG), where only autologous fat flap transfer was performed without tissue expansion. Tissue expansion control group (TECG) did not perform autologous fat flap transfer but only skin tissue expansion on the back. Blank control group (BCG) has not received any surgery. In each group of 20 rats, skin, and fat flaps of the dilated area were sampled at four time points (7, 14, 21, and 28 days, n = 5), and the immediate skin retraction rate of the expanded area in the EG and TECG groups was measured to evaluate the expansion effect. GFP⁺ADSCs were observed to demonstrate whether they were facilitated by tissue expansion and migrated from autologous fat flaps to skin. Our study supported that fat layer construction prior to skin expansion helps to promote skin growth. The promotion may be related to the migration of ADSCs from adipose to dermis by compression, and ADSCs migrating to dermis further promote skin stretching through direct differentiation or paracrine cytokines to promote cell proliferation and collagen synthesis.

Thoracic aortic dissection (TAD) is a life-threatening condition characterized by medial degeneration and vascular smooth muscle cell (VSMC) dysfunction, with no effective medical therapy currently available. The underlying pathological mechanisms of TAD remain incompletely understood. In this study, we used a nonintegrated episomal vector-based reprograming system to generate induced pluripotent stem cells (iPSCs) from TAD patients and healthy controls. Both TAD and normal iPSCs expressed key pluripotency markers and were capable of differentiating into the three germ layers in vitro. These iPSCs were differentiated into vascular smooth muscle cells (VSMCs) through a mesodermal intermediate for disease modeling. VSMCs derived from both TAD and normal iPSCs expressed smooth muscle α-actin (α-SMA), calponin (CNN), and SM22α. However, TAD-iPSC-derived VSMCs exhibited significantly reduced contraction in response to carbachol stimulation compared to their normal counterparts. Whole-exome sequencing identified a mutation in the COL4A2 gene (c.392G > T, p. R131M) in TAD-iPSCs. This mutation was associated with reduced collagen IV expression and increased expression of collagen I and III in TAD-VSMCs, both with and without TGF-β stimulation. Furthermore, noncanonical TGF-β signaling was hyperactivated in TAD-VSMCs, accompanied by elevated MMP9 expression. This patient-specific iPSC model reveals key dysfunctions in VSMC contractility, extracellular matrix (ECM) protein expression, and dysregulated TGF-β signaling, which may contribute to TAD pathogenesis. Our findings provide new insights into the molecular mechanisms driving TAD and offer a platform for future therapeutic development.