Mesenchymal Stem Cells for Regenerative Medicine

Bushen Huoxue recipe ameliorates ovarian function via promoting BMSCs proliferation and homing to ovaries in POI mice

BACKGROUND

Premature ovarian insufficiency (POI) is a tricky puzzle in the field of female reproductive medicine. Bushen Huoxue recipe (BHR), a traditional Chinese medicine compound based on the combination of kidney-tonifying and blood-activating functions, has shown excellent efficacy in improving female irregular menstruation, POI, and infertility. However, the potential mechanism of BHR in POI treatment has not yet been elucidated. Bone marrow mesenchymal stem cells (BMSCs), a type of pluripotent stem cells, have received increasing attention for their significant role in improving ovarian function and restoring fertility in women with POI.

PURPOSE

This study aimed to evaluate the therapeutic effect of BHR in POI mice and explore its potential mechanism.

METHODS

A POI mouse model was established with a single intraperitoneal injection of 120 mg/kg cyclophosphamide (CTX). Distilled water, BHR, or dehydroepiandrosterone was administered via gavage for 28 consecutive days. The effect of BHR on ovarian function in POI mice was evaluated by assessing the estrous cycle, ovarian morphology, follicular development, hormone levels, and angiogenesis. The proportion of BMSCs in bone marrow, peripheral blood, and ovary was analyzed via flow cytometry, and the level of molecules mediating migration and homing in ovary was measured. Cell viability assays, scratch healing assays and transwell migration assays were performed to explore the effect of BHR on BMSCs proliferation and migration in vitro, and its potential mechanism was explored.

RESULTS

BHR significantly ameliorated estrous cycle disorders, hormone disorders, ovarian morphology, ovarian microvascular formation, and ovarian reserve in POI mice. Meanwhile, the number of BMSCs number in the bone marrow, peripheral blood, and ovary was apparently increased. Of note, BHR increased the level of hepatocyte growth factor (HGF)/cellular mesenchymal epithelial transition factor (cMET) and stromal cell-derived factor-1(SDF-1)/CXC chemokine receptor 4 (CXCR4) in the ovaries of POI mice. Moreover, BHR treatment promoted BMSCs proliferation and migration in vitro, with a significant increase in the level of proliferating cell nuclear antigen, cMET, and CXCR4.

CONCLUSIONS

BHR effectively restored ovarian reserve, ovarian function, and ovarian angiogenesis in CTX-induced POI mice. In addition, BHR promoted BMSCs proliferation, migration, and homing to the ovary, which was mediated by the SDF-1/CXCR4 and HGF/cMET signaling axis. Finally, the amelioration of ovarian reserve and ovarian function in CTX-induced POI mice by BHR may be related to its promotion of endogenous BMSCs proliferation and homing.

Effect of human bone marrow mesenchymal stem cell-derived microvesicles on the apoptosis of the multiple myeloma cell line U266

BACKGROUND

Microvesicles are membraned particles produced by different types of cells recently investigated for anticancer purposes. The current study aimed to investigate the effects of human bone marrow mesenchymal stem cell-derived microvesicles (BMSC-MVs) on the multiple myeloma cell line U266. BMSC-MVs were isolated from BMSCs via ultracentrifugation and characterized using transmission electron microscopy (TEM) and dynamic light scattering (DLS). U266 cells were treated with 15, 30, 60, and 120 µg/mL BMSC-MVs for three and seven days and the effects of treatment in terms of viability, cytotoxicity, and DNA damage were investigated via the MTT assay, lactate dehydrogenase (LDH) assay, and 8‑hydroxy-2'-deoxyguanosine (8‑OHdG) measurement, respectively. Moreover, the apoptosis rate of the U266 cells treated with 60 µg/mL BMSC-MVs was also assessed seven days following treatment via flow cytometry. Ultimately, the expression level of BCL2, BAX, and CCND1 by the U266 cells was examined seven days following treatment with 60 µg/mL BMSC-MVs using qRT-PCR.

RESULTS

BMSC-MVs had an average size of ~ 410 nm. According to the MTT and LDH assays, BMSC-MV treatment reduced the U266 cell viability and mediated cytotoxic effects against them, respectively. Moreover, elevated 8‑OHdG levels following BMSC-MV treatment demonstrated a dose-dependent increase of DNA damage in the treated cells. BMSC-MV-treated U266 cells also exhibited an increased apoptosis rate after seven days of treatment. The expression level of BCL2 and CCND1 decreased in the treated cells whereas the BAX expression demonstrated an incremental pattern.

CONCLUSIONS

Our findings accentuate the therapeutic benefit of BMSC-MVs against the multiple myeloma cell line U266 and demonstrate how microvesicles could be of therapeutic advantage. Future in vivo studies could further corroborate these findings.

From Time to Timer in Wound Healing Through the Regeneration

Hard-to-heal wounds are an important public health issue worldwide, with a significant impact on the quality of life of patients. It is estimated that approximately 1-2% of the global population suffers from difficult wounds, which can be caused by a variety of factors such as trauma, infections, chronic diseases like diabetes or obesity, or poor health conditions. Hard-to-heal wounds are often characterized by a slow and complicated healing process, which can lead to serious complications such as infections, pressure ulcers, scar tissue formation, and even amputations. These complications can have a significant impact on the mobility, autonomy, and quality of life of patients, leading to an increase in healthcare and social costs associated with wound care. The preparation of the wound bed is a key concept in the management of hard-to-heal wounds, with the aim of promoting an optimal environment for healing. The TIME (Tissue, Infection/Inflammation, Moisture, Edge) model is a systematic approach used to assess and manage wounds in a targeted and personalized way. The concept of TIMER, expanding the TIME model, further focuses on regenerative processes, paying particular attention to promoting tissue regeneration and wound healing in a more effective and comprehensive way. The new element introduced in the TIMER model is "Regeneration", which highlights the importance of activating and supporting tissue regeneration processes to promote complete and lasting wound healing. Regenerative therapies can include a wide range of approaches, including cellular therapies, growth factors, bioactive biomaterials, stem cell therapies, and growth factor therapies. These therapies aim to promote the formation of new healthy tissues, reduce inflammation, improve vascularization, and stimulate cellular proliferation to accelerate wound closure and prevent complications. Thanks to continuous progress in research and development of regenerative therapies, more and more patients suffering from difficult wounds can benefit from innovative and promising solutions to promote faster and more effective healing, improve quality of life, and reduce the risk of long-term complications.

Mesenchymal stem cells biological and biotechnological advances: Implications for clinical applications

BACKGROUND

Mesenchymal stem cells (MSCs) are multipotent stem cells that are able to differentiate into multiple lineages including bone, cartilage, muscle and fat. They hold immunomodulatory properties and therapeutic ability to treat multiple diseases, including autoimmune and chronic degenerative diseases. In this article, we reviewed the different biological properties, applications and clinical trials of MSCs. Also, we discussed the basics of manufacturing conditions, quality control, and challenges facing MSCs in the clinical setting.

METHODS

Extensive review of the literature was conducted through the databases PubMed, Google Scholar, and Cochrane. Papers published since 2015 and covering the clinical applications and research of MSC therapy were considered. Furthermore, older papers were considered when referring to pioneering studies in the field.

RESULTS

The most widely studied stem cells in cell therapy and tissue repair are bone marrow-derived mesenchymal stem cells. Adipose tissue-derived stem cells became more common and to a lesser extent other stem cell sources e.g., foreskin derived MSCs. MSCs therapy were also studied in the setting of COVID-19 infections, ischemic strokes, autoimmune diseases, tumor development and graft rejection. Multiple obstacles, still face the standardization and optimization of MSC therapy such as the survival and the immunophenotype and the efficiency of transplanted cells. MSCs used in clinical settings displayed heterogeneity in their function despite their extraction from healthy donors and expression of similar surface markers.

CONCLUSION

Mesenchymal stem cells offer a rising therapeutic promise in various diseases. However, their potential use in clinical applications requires further investigation.

MiR-483-3p promotes dental pulp stem cells osteogenic differentiation via the MAPK signaling pathway by targeting ARRB2

Human dental pulp stem cells (DPSCs) have become an important component for bone tissue engineering and regenerative medicine due to their ability to differentiate into osteoblast precursors. Two miRNA chip datasets (GSE138180 and E-MTAB-3077) of DPSCs osteogenic differentiation were analyzed respectively to find the expression of miR-483-3p significantly increased in the differentiated groups. We further confirmed that miR-483-3p continued to overexpress during osteogenic differentiation of DPSCs, especially reaching its peak on the 7th day. Moreover, miR-483-3p could significantly promote the expression of osteogenic markers including RUNX2 and OSX, and activate MAPK signaling pathway by inducing phosphorylation of ERK, p38, and JNK. In addition, as a significant gene within the MAPK signaling pathway, ARRB2 was identified as the target gene of miR-483-3p by bioinformatic prediction and experimental verification. In conclusion, we identified miR-483-3p could promote osteogenic differentiation of DPSCs via the MAPK signaling pathway by targeting ARRB2.

Extracellular vesicles in nanomedicine and regenerative medicine: A review over the last decade

Small extracellular vesicles (sEVs) are known to be secreted by a vast majority of cells. These sEVs, specifically exosomes, induce specific cell-to-cell interactions and can activate signaling pathways in recipient cells through fusion or interaction. These nanovesicles possess several desirable properties, making them ideal for regenerative medicine and nanomedicine applications. These properties include exceptional stability, biocompatibility, wide biodistribution, and minimal immunogenicity. However, the practical utilization of sEVs, particularly in clinical settings and at a large scale, is hindered by the expensive procedures required for their isolation, limited circulation lifetime, and suboptimal targeting capacity. Despite these challenges, sEVs have demonstrated a remarkable ability to accommodate various cargoes and have found extensive applications in the biomedical sciences. To overcome the limitations of sEVs and broaden their potential applications, researchers should strive to deepen their understanding of current isolation, loading, and characterization techniques. Additionally, acquiring fundamental knowledge about sEVs origins and employing state-of-the-art methodologies in nanomedicine and regenerative medicine can expand the sEVs research scope. This review provides a comprehensive overview of state-of-the-art exosome-based strategies in diverse nanomedicine domains, encompassing cancer therapy, immunotherapy, and biomarker applications. Furthermore, we emphasize the immense potential of exosomes in regenerative medicine.

Evaluation of the effect of dimethyl fumarate on human bone marrow-derived mesenchymal stem cells using bottom-up proteomics

Mesenchymal stem cells (MSCs) have potential as a viable treatment option in the field of regenerative medicine, but MSC-based therapy needs to be more efficient. Preconditioning is a method to improve MSC-based therapy, and dimethyl fumarate (DMF) - an agent that can enhance the antioxidative capacity of cells - can be considered for preconditioning of MSCs. In this study, we treated bone marrow-derived MSCs with DMF and evaluated their proteome using bottom-up proteomics. The MSCs were exposed to 10 μM DMF for 24 h, followed by lysis with an SDS solution, digestion with trypsin using an s-trap column, and analysis using nanoLC-MS/MS, which identified 2262 proteins with confidence. Bioinformatic analysis of the identified proteins revealed 47 upregulated proteins and 81 downregulated proteins upon DMF treatment. Pathway enrichment analysis suggested a possible decrease in autophagy and a decrease in the activity of the TCA cycle, while indicating a potential increase in proliferation and antioxidant activity in DMF-treated MSCs compared to untreated MSCs. Our findings suggest that DMF can enhance the proliferation of MSCs and increase their stability, and that preconditioning could improve the therapeutic efficacy of MSCs for the treatment of regenerative diseases.

The Main Mechanisms of Mesenchymal Stem Cell-Based Treatments against COVID-19

BACKGROUND

Coronavirus disease 2019 (COVID-19) has a clinical manifestation of hypoxic respiratory failure and acute respiratory distress syndrome. However, COVID-19 still lacks of effective clinical treatments so far. As a promising potential treatment against COVID-19, stem cell therapy raised recently and had attracted much attention. Here we review the mechanisms of mesenchymal stem cell-based treatments against COVID-19, and provide potential cues for the effective control of COVID-19 in the future.

METHODS

Literature is obtained from databases PubMed and Web of Science. Key words were chosen for COVID- 19, acute respiratory syndrome coronavirus 2, mesenchymal stem cells, stem cell therapy, and therapeutic mechanism. Then we summarize and critically analyze the relevant articles retrieved.

RESULTS

Mesenchymal stem cell therapy is a potential effective treatment against COVID-19. Its therapeutic efficacy is mainly reflected in reducing severe pulmonary inflammation, reducing lung injury, improving pulmonary function, protecting and repairing lung tissue of the patients. Possible therapeutic mechanisms might include immunoregulation, anti-inflammatory effect, tissue regeneration, anti-apoptosis effect, antiviral, and antibacterial effect, MSC - EVs, and so on.

CONCLUSION

Mesenchymal stem cells can effectively treat COVID-19 through immunoregulation, anti-inflammatory, tissue regeneration, anti-apoptosis, anti-virus and antibacterial, MSC - EVs, and other ways. Systematically elucidating the mechanisms of mesenchymal stem cell-based treatments for COVID-19 will provide novel insights into the follow-up research and development of new therapeutic strategies in next step.

Enhancement of the function of mesenchymal stem cells by using a GMP-grade three-dimensional hypoxic large-scale production system

Background

Efficiently increasing the production of clinical-grade mesenchymal stem cells (MSCs) is crucial for clinical applications. Challenges with the current planar culture methods include scalability issues, labour intensity, concerns related to cell senescence, and heterogeneous responses. This study aimed to establish a large-scale production system for MSC generation. In addition, a comparative analysis of the biological differences between MSCs cultured under various conditions was conducted.

Methods and materials

We developed a GMP-grade three-dimensional hypoxic large-scale production (TDHLSP) system for MSCs using self-fabricated glass microcarriers and a multifunctional bioreactor. Different parameters, including cell viability, cell diameter, immunophenotype, morphology, karyotype, and tumourigenicity were assessed in MSCs cultured using different methods. Single-cell RNA sequencing (scRNA-seq) revealed pathways and genes associated with the enhanced functionality of MSCs cultured in three dimensions under hypoxic conditions (3D_Hypo MSCs). Moreover, CD142 knockdown in 3D_Hypo MSCs confirmed its in vitro functions.

Results

Inoculating 2 × 108 MSCs into a 2.6 L bioreactor in the TDHLSP system resulted in a final scale of 4.6 × 109 3D_Hypo MSCs by day 10. The 3D_Hypo MSCs retained characteristics of the 2D MSCs, demonstrating their genomic stability and non-tumourigenicity. Interestingly, the subpopulations of 3D_Hypo MSCs exhibited a more uniform distribution and a closer relationship than those of 2D MSCs. The heterogeneity of MSCs was strongly correlated with 'cell cycle' and 'stroma/mesenchyme', with 3D_Hypo MSCs expressing higher levels of activated stroma genes. Compared to 2D MSCs, 3D_Hypo MSCs demonstrated enhanced capabilities in blood vessel formation, TGF-β1 secretion, and inhibition of BV2 proliferation, with maintenance of Senescence-Associated β-Galactosidase (SA-β-gal) negativity. However, the enhanced functions of 3D_Hypo MSCs decreased upon the downregulation of CD142 expression.

Conclusion

The TDHLSP system led to a high overall production of MSCs and promoted uniform distribution of MSC clusters. This cultivation method also enhanced key cellular properties, such as angiogenesis, immunosuppression, and anti-aging. These functionally improved and uniform MSC subpopulations provide a solid basis for the clinical application of stem cell therapies.

Murine bone-derived mesenchymal stem cells undergo molecular changes after a single passage in culture

The rarity of the mesenchymal stem cell (MSC) population poses a significant challenge for MSC research. Therefore, these cells are often expanded in vitro, prior to use. However, long-term culture has been shown to alter primary MSC properties. Additionally, early passage primary MSCs in culture are often assumed to represent the primary MSC population in situ, however, little research has been done to support this. Here, we compared the transcriptomic profiles of murine MSCs freshly isolated from the bone marrow to those that had been expanded in culture for 10 days. We identified that a single passage in culture extensively altered MSC molecular signatures associated with cell cycling, differentiation and immune response. These findings indicate the critical importance of the MSC source, highlighting the need for optimization of culture conditions to minimize the impact on MSC biology and a transition towards in vivo methodologies for the study of MSC function.

Revolutionizing type 1 diabetes management: Exploring oral insulin and adjunctive treatments

Type 1 diabetes (T1D) is a chronic autoimmune condition that affects millions of people worldwide. Insulin pumps or injections are the standard treatment options for this condition. This article provides a comprehensive overview of the several type 1 diabetes treatment options, focusing on oral insulin. The article is divided into parts that include immune-focused treatments, antigen vaccination, cell-directed interventions, cytokine-directed interventions, and non-immunomodulatory adjuvant therapy. Under the section on non-immunomodulatory adjunctive treatment, the benefits and drawbacks of medications such as metformin, amylin, sodium-glucose cotransporter inhibitors, glucagon-like peptide-1 receptor agonists (GLP-1 Ras), and verapamil are discussed. The article also discusses the advantages of oral insulin, including increased patient compliance and more dependable and regular blood sugar control. However, several variables, including the enzymatic and physical barriers of the digestive system, impair the administration of insulin via the mouth. Researchers have looked at a few ways to get over these challenges, such as changing the structure of the insulin molecule, improving absorption with the use of absorption enhancers or nanoparticles, and taking oral insulin together with other medications. Even with great advancements in the use of these treatment strategies, T1D still needs improvement in the therapeutic difficulties. Future studies in these areas should focus on creating tailored immunological treatments, looking into combination medications, and refining oral insulin formulations in an attempt to better control Type 1 Diabetes. The ultimate objective is to create accurate, customized strategies that will enhance glycemic management and the quality of life for individuals with the condition.

Pyroptotic macrophages induce disruption of glutamate metabolism in periodontal ligament stem cells contributing to their compromised osteogenic potential

Macrophage pyroptosis is of key importance to host defence against pathogen infections and may participate in the progression and recovery of periodontitis. However, the role of pyroptotic macrophages in regulating periodontal ligament stem cells (PDLSCs), the main cell source for periodontium renewal, remains unclear. First, we found that macrophage pyroptosis were enriched in gingiva tissues from periodontitis patients compared with those of healthy people through immunofluorescence. Then the effects of pyroptotic macrophages on the PDLSC osteogenic differentiation were investigated in a conditioned medium (CM)-based coculture system in vitro. CM derived from pyroptotic macrophages inhibited the osteogenic differentiation-related gene and protein levels, ALP activity and mineralized nodule formation of PDLSCs. The osteogenic inhibition of CM was alleviated when pyroptosis was inhibited by VX765. Further, untargeted metabolomics showed that glutamate limitation may be the underlying mechanism. However, exogenous glutamate supplementation aggravated the CM-inhibited osteogenic differentiation of PDLSCs. Moreover, CM increased extracellular glutamate and decreased intracellular glutamate levels of PDLSCs, and enhanced the gene and protein expression levels of system xc - (a cystine/glutamate antiporter). After adding cystine to CM-based incubation, the compromised osteogenic potency of PDLSCs was rescued. Our data suggest that macrophage pyroptosis is related to the inflammatory lesions of periodontitis. Either pharmacological inhibition of macrophage pyroptosis or nutritional supplements to PDLSCs, can rescue the compromised osteogenic potency caused by pyroptotic macrophages.

Mesenchymal Stromal Cells: New Generation Treatment of Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) is a chronic inflammatory disease of the gastrointestinal tract, which has a high recurrence rate and is incurable due to a lack of effective treatment. Mesenchymal stromal cells (MSCs) are a class of pluripotent stem cells that have recently received a lot of attention due to their strong self-renewal ability and immunomodulatory effects, and a large number of experimental and clinical models have confirmed the positive therapeutic effect of MSCs on IBD. In preclinical studies, MSC treatment for IBD relies on MSCs paracrine effects, cell-to-cell contact, and its mediated mitochondrial transfer for immune regulation. It also plays a therapeutic role in restoring the intestinal mucosal barrier through the homing effect, regulation of the intestinal microbiome, and repair of intestinal epithelial cells. In the latest clinical trials, the safety and efficacy of MSCs in the treatment of IBD have been confirmed by transfusion of autologous or allogeneic bone marrow, umbilical cord, and adipose MSCs, as well as their derived extracellular vesicles. However, regarding the stable and effective clinical use of MSCs, several concerns emerge, including the cell sources, clinical management (dose, route and frequency of administration, and pretreatment of MSCs) and adverse reactions. This article comprehensively summarizes the effects and mechanisms of MSCs in the treatment of IBD and its advantages over conventional drugs, as well as the latest clinical trial progress of MSCs in the treatment of IBD. The current challenges and future directions are also discussed. This review would add knowledge into the understanding of IBD treatment by applying MSCs.

Regulation of mesenchymal stem cell differentiation by autophagy

Autophagy, a process that isolates intracellular components and fuses them with lysosomes for degradation, plays an important cytoprotective role by eliminating harmful intracellular substances and maintaining cellular homeostasis. Mesenchymal stem cells (MSCs) are multipotent progenitor cells with the capacity for self-renewal that can give rise to a subset of tissues and therefore have potential in regenerative medicine. However, a variety of variables influence the biological activity of MSCs following their proliferation and transplantation in vitro. The regulation of autophagy in MSCs represents a possible mechanism that influences MSC differentiation properties under the right microenvironment, affecting their regenerative and therapeutic potential. However, a deeper understanding of exactly how autophagy is mobilized to function as well as clarifying the mechanisms by which autophagy promotes MSCs differentiation is still needed. Here, we review the current literature on the complex link between MSCs differentiation and autophagy induced by various extracellular or intracellular stimuli and the molecular targets that influence MSCs lineage determination, which may highlight the potential regulation of autophagy on MSCs' therapeutic capacity, and provide a broader perspective on the clinical application of MSCs in the treatment of a wide range of diseases.

Human umbilical cord mesenchymal stem cells combined with porcine small intestinal submucosa promote the healing of full-thickness skin injury in SD rats

Aim: To assess the therapeutic potential of human umbilical cord mesenchymal stem cells (hUCMSCs) combined with porcine small intestinal submucosa (SIS) on full-thickness skin injuries in rats. Methods: We established full-thickness skin injury models in Sprague-Dawley rats, dividing them into blank control, SIS, hUCMSCs and hUCMSCs combined with SIS. We monitored wound healing, scores and area, and analyzed inflammatory cells, microvessel density and collagen fibers after 12 days. Results: The blank group showed no healing, forming a scar of 0.6 × 0.5 cm2, while SIS and hUCMSCs groups exhibited incomplete healing with 0.4 × 0.5 cm2 scabs. Wound healing was significantly better in the hUCMSCs combined with the SIS group. Conclusion: Local application of hUCMSCs combined with SIS enhances full-thickness skin injury wound healing in rats.

hTERT-Immortalized Mesenchymal Stem Cell-Derived Extracellular Vesicles: Large-Scale Manufacturing, Cargo Profiling, and Functional Effects in Retinal Epithelial Cells

As the economic burden associated with vision loss and ocular damage continues to rise, there is a need to explore novel treatment strategies. Extracellular vesicles (EVs) are enriched with various biological cargo, and there is abundant literature supporting the reparative and immunomodulatory properties of stem cell EVs across a broad range of pathologies. However, one area that requires further attention is the reparative effects of stem cell EVs in the context of ocular damage. Additionally, most of the literature focuses on EVs isolated from primary stem cells; the use of EVs isolated from human telomerase reverse transcriptase (hTERT)-immortalized stem cells has not been thoroughly examined. Using our large-scale EV-manufacturing platform, we reproducibly manufactured EVs from hTERT-immortalized mesenchymal stem cells (MSCs) and employed various methods to characterize and profile their associated cargo. We also utilized well-established cell-based assays to compare the effects of these EVs on both healthy and damaged retinal pigment epithelial cells. To the best of our knowledge, this is the first study to establish proof of concept for reproducible, large-scale manufacturing of hTERT-immortalized MSC EVs and to investigate their potential reparative properties against damaged retinal cells. The results from our studies confirm that hTERT-immortalized MSC EVs exert reparative effects in vitro that are similar to those observed in primary MSC EVs. Therefore, hTERT-immortalized MSCs may represent a more consistent and reproducible platform than primary MSCs for generating EVs with therapeutic potential.

Emerging Strategies in Mesenchymal Stem Cell-Based Cardiovascular Therapeutics

Cardiovascular diseases continue to challenge global health, demanding innovative therapeutic solutions. This review delves into the transformative role of mesenchymal stem cells (MSCs) in advancing cardiovascular therapeutics. Beginning with a historical perspective, we trace the development of stem cell research related to cardiovascular diseases, highlighting foundational therapeutic approaches and the evolution of cell-based treatments. Recognizing the inherent challenges of MSC-based cardiovascular therapeutics, which range from understanding the pro-reparative activity of MSCs to tailoring patient-specific treatments, we emphasize the need to refine the pro-regenerative capacity of these cells. Crucially, our focus then shifts to the strategies of the fourth generation of cell-based therapies: leveraging the secretomic prowess of MSCs, particularly the role of extracellular vesicles; integrating biocompatible scaffolds and artificial sheets to amplify MSCs' potential; adopting three-dimensional ex vivo propagation tailored to specific tissue niches; harnessing the promise of genetic modifications for targeted tissue repair; and institutionalizing good manufacturing practice protocols to ensure therapeutic safety and efficacy. We conclude with reflections on these advancements, envisaging a future landscape redefined by MSCs in cardiovascular regeneration. This review offers both a consolidation of our current understanding and a view toward imminent therapeutic horizons.

Collagen-Mesenchymal Stem Cell Microspheres Embedded in Hyaluronic Acid Solutions as Biphasic Stem Niche Delivery Systems for Pulmonary Differentiation

Cell therapy has the potential to become a feasible solution for several diseases, such as those related to the lungs and airways, considering the more beneficial intratracheal administration route. However, in lung diseases, an impaired pulmonary extracellular matrix (ECM) precludes injury resolution with a faulty engraftment of mesenchymal stem cells (MSCs) at the lung level. Furthermore, a shielding strategy to avoid cell damage as well as cell loss due to backflow through the injection path is required. Here, an approach to deliver cells encapsulated in a biomimetic stem niche is used, in which the interplay between cells and physiological lung ECM constituents, such as collagen and hyaluronic acid (HA), can occur. To this aim, a biphasic delivery system based on MSCs encapsulated in collagen microspheres (mCOLLs) without chemical modification and embedded in an injectable HA solution has been developed. Such biphasic delivery systems can both increase the mucoadhesive properties at the site of interest and improve cell viability and pulmonary differentiation. Rheological results showed a similar viscosity at high shear rates compared to the MSC suspension used in intratracheal administration. The size of the mCOLLs can be controlled, resulting in a lower value of 200 μm, suitable for delivery in alveolar sacs. Biological results showed that mCOLLs maintained good cell viability, and when they were suspended in lung medium implemented with low molecular weight HA, the differentiation ability of the MSCs was further enhanced compared to their differentiation ability in only lung medium. Overall, the results showed that this strategy has the potential to improve the delivery and viability of MSCs, along with their differentiation ability, in the pulmonary lineage.

Mesenchymal stem cell secretome for regenerative medicine: Where do we stand?

BACKGROUND

Mesenchymal stem cell (MSC)-based therapies have yielded beneficial effects in a broad range of preclinical models and clinical trials for human diseases. In the context of MSC transplantation, it is widely recognized that the main mechanism for the regenerative potential of MSCs is not their differentiation, with in vivo data revealing transient and low engraftment rates. Instead, MSCs therapeutic effects are mainly attributed to its secretome, i.e., paracrine factors secreted by these cells, further offering a more attractive and innovative approach due to the effectiveness and safety of a cell-free product.

AIM OF REVIEW

In this review, we will discuss the potential benefits of MSC-derived secretome in regenerative medicine with particular focus on respiratory, hepatic, and neurological diseases. Both free and vesicular factors of MSC secretome will be detailed. We will also address novel potential strategies capable of improving their healing potential, namely by delivering important regenerative molecules according to specific diseases and tissue needs, as well as non-clinical and clinical studies that allow us to dissect their mechanisms of action.

KEY SCIENTIFIC CONCEPTS OF REVIEW

MSC-derived secretome includes both soluble and non-soluble factors, organized in extracellular vesicles (EVs). Importantly, besides depending on the cell origin, the characteristics and therapeutic potential of MSC secretome is deeply influenced by external stimuli, highlighting the possibility of optimizing their characteristics through preconditioning approaches. Nevertheless, the clarity around their mechanisms of action remains ambiguous, whereas the need for standardized procedures for the successful translation of those products to the clinics urges.

Comparison of the mesodermal differentiation potential between embryonic stem cells and scalable induced pluripotent stem cells

BACKGROUND

Mesenchymal stem cells (MSCs) have promising potential in clinical application, whereas their limited amount and sources hinder their bioavailability. Embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs) have become prominent options in regenerative medicine as both possess the ability to differentiate into MSCs.

METHODS

Recently, our research team has successfully developed human leukocyte antigen (HLA)-homozygous iPSC cell lines with high immune compatibility, covering 13.5% of the Taiwanese population. As we deepen our understanding of the differences between these ESCs and HLA-homozygous iPSCs, our study focused on morphological observations and flow cytometry analysis of specific surface marker proteins during the differentiation of ESCs and iPSCs into MSCs.

RESULTS

The results showed no significant differences between the two pluripotent stem cells, and both of them demonstrated the equivalent ability to further differentiate into adipose, cartilage, and bone cells.

CONCLUSION

Our research revealed that these iPSCs with high immune compatibility exhibit the same differentiation potential as ESCs, enhancing the future applicability of highly immune-compatible iPSCs.

Mesenchymal stem cell-derived exosomes improve neurogenesis and cognitive function of mice with methamphetamine addiction: A novel treatment approach

BACKGROUND

Methamphetamine (METH) is a psychostimulant substance with highly addictive and neurotoxic effects, but no ideal treatment option exists to improve METH-induced neurocognitive deficits. Recently, mesenchymal stem cells (MSCs)-derived exosomes have raised many hopes for treating neurodegenerative sequela of brain disorders. This study aimed to determine the therapeutic potential of MSCs-derived exosomes on cognitive function and neurogenesis of METH-addicted rodents.

METHODS

Male BALB/c mice were subjected to chronic METH addiction, followed by intravenous administration of bone marrow MSCs-derived exosomes. Then, the spatial memory and recognition memory of animals were assessed by the Barnes maze and the novel object recognition test (NORT). The neurogenesis-related factors, including NeuN and DCX, and the expression of Iba-1, a microglial activation marker, were assessed in the hippocampus by immunofluorescence staining. Also, the expression of inflammatory cytokines, including TNF-α and NF-κB, were evaluated by western blotting.

RESULTS

The results showed that BMSCs-exosomes improved the time spent in the target quadrant and correct-to-wrong relative time in the Barnes maze. Also, NORT's discrimination index (DI) and recognition index (RI) were improved following exosome therapy. Additionally, exosome therapy significantly increased the expression of NeuN and DCX in the hippocampus while decreasing the expression of inflammatory cytokines, including TNF-α and NF-κB. Besides, BMSC-exosomes down-regulated the expression of Iba-1.

CONCLUSION

Our findings indicate that BMSC-exosomes mitigated METH-caused cognitive dysfunction by improving neurogenesis and inhibiting neuroinflammation in the hippocampus.

The design of an RGD in situ sustained delivery system utilizing scallop byssal protein through genetic engineering

Although bioactive peptides enhancing bone healing have demonstrated effectiveness in treating bone defects, in vivo instability poses a challenge to their clinical application. Currently reported peptide delivery systems do not meet the demands of bone tissue repair regarding stability and peptide release efficacy. Herein, the self-assembling recombinant chimeric protein (Sbp5-2RGD) is developed by genetic engineering with cell adhesion peptide RGD as the targeted peptide and a newly discovered scallop byssal-derived protein Sbp5-2 that can assemble into wet stable films as the structural domain. In vitro studies show that the Sbp5-2RGD film exhibits excellent extensibility and biocompatibility. In vitro and in vivo degradation experiments demonstrate that the film remains stable due to the layer-by-layer degradation mode, resulting in sustained delivery of RGD in situ for up to 4 weeks. Consequently, the film can effectively promote osteogenesis, which accelerates bone defect healing and the implants osseointegration. Cell-level studies further show that the film up-regulates the expression of genes and proteins (ALP, OCN, OSX, OPN, RUNX2, VEGF) associated with osteogenesis and angiogenesis. Overall, this novel protein film represents an intelligent platform for peptide immobilization, protection, and release through its self-assembly, dense structure, and degradation mode, providing a therapeutic strategy for bone repair.

Extracellular Vesicles: the Next Frontier in Pregnancy Research

Extracellular vehicles (EVs) have been involved in several aspects of pregnancy, including endometrial receptivity, embryo implantation, and embryo-maternal communication showing them associated with pregnancy disorders, such as preeclampsia, gestational diabetes mellitus, and preterm birth. Further research is warranted to fully comprehend the exact pathophysiological roles of EVs and to develop new therapies targeting EVs thereby improving pregnancy outcomes. Herein, we review the recent knowledge on the multifaceted roles of EVs during pregnancy and address the majority of the molecular interactions between EVs, maternal, and fetal cells with an emphasis on disorders of pregnancy under the influence of EVs. Moreover, we also discuss its applications in clinical trials followed by prospects.

Improving the mechanical and biological functions of cell sheet constructs: The interplay of human-derived periodontal ligament stem cells, endothelial cells and plasma rich in growth factors

OBJECTIVE

The aim of this study was to produce and characterize triple-layered cell sheet constructs with varying cell compositions combined or not with the fibrin membrane scaffold obtained by the technology of Plasma Rich in Growth Factors (mPRGF).

MATERIALS AND METHODS

Human primary cultures of periodontal ligament stem cells (hPDLSCs) were isolated, and their stemness nature was evaluated. Three types of triple-layered composite constructs were generated, composed solely of hPDLSCs or combined with human umbilical vein endothelial cells (HUVECs), either as a sandwiched endothelial layer or as coculture sheets of both cell phenotypes. These three triple-layered constructs were also manufactured using mPRGF as cell sheets' support. Necrosis, glucose consumption, secretion of extracellular matrix proteins and synthesis of proangiogenic factors were determined. Histological evaluations and proteomic analyses were also performed.

RESULTS

The inclusion of HUVECs did not clearly improve the properties of the multilayered constructs and yet hindered their optimal conformation. The presence of mPRGF prevented the shrinkage of cell sheets, stimulated the metabolic activity and increased the matrix synthesis. At the proteome level, mPRGF conferred a dramatic advantage to the hPDLSC constructs in their ability to provide a suitable environment for tissue regeneration by inducing the expression of proteins necessary for bone morphogenesis and cellular proliferation.

CONCLUSIONS

hPDLSCs' triple-layer construct onto mPRGF emerges as the optimal structure for its use in regenerative therapeutics.

CLINICAL RELEVANCE

These results suggest the suitability of mPRGF as a promising tool to support cell sheet formation by improving their handling and biological functions.

A case series on safety and tolerability of human umbilical cord-derived mesenchymal stem cells on patients in Malaysia

Umbilical cord-derived mesenchymal stem cells for regenerative therapy are a promising treatment option for chronic illnesses. Umbilical cord-derived mesenchymal stem cells offer several advantages over other sources, which makes them an attractive option in tissue repair and regeneration. This clinical study describes a 1-year follow-up on the safety and tolerance of umbilical cord-derived mesenchymal stem cell therapy on nine patients in Malaysia. Patients were assessed for adverse effects, and liver function tests were carried out on both pre- and post-treatments. Umbilical cord-derived mesenchymal stem cells' effectiveness and safety were assessed by follow-up evaluations. All nine patients responded positively towards umbilical cord-derived mesenchymal stem cell therapy, without any adverse effects. After umbilical cord-derived mesenchymal stem cell therapy, a significant improvement was observed in liver functioning test outcomes, as haematological parameters and tumour markers were stable. The present study concludes that umbilical cord-derived mesenchymal stem cell therapy is well tolerated by Malaysian patients; however, further clinical screening must be done over a large number of patients population.

The Tumor Stroma of Squamous Cell Carcinoma: A Complex Environment That Fuels Cancer Progression

The tumor microenvironment (TME), a complex assembly of cellular and extracellular matrix (ECM) components, plays a crucial role in driving tumor progression, shaping treatment responses, and influencing metastasis. This narrative review focuses on the cutaneous squamous cell carcinoma (cSCC) tumor stroma, highlighting its key constituents and their dynamic contributions. We examine how significant changes within the cSCC ECM-specifically, alterations in fibronectin, hyaluronic acid, laminins, proteoglycans, and collagens-promote cancer progression, metastasis, and drug resistance. The cellular composition of the cSCC TME is also explored, detailing the intricate interplay of cancer-associated fibroblasts (CAFs), mesenchymal stem cells (MSCs), endothelial cells, pericytes, adipocytes, and various immune cell populations. These diverse players modulate tumor development, angiogenesis, and immune responses. Finally, we emphasize the TME's potential as a therapeutic target. Emerging strategies discussed in this review include harnessing the immune system (adoptive cell transfer, checkpoint blockade), hindering tumor angiogenesis, disrupting CAF activity, and manipulating ECM components. These approaches underscore the vital role that deciphering TME interactions plays in advancing cSCC therapy. Further research illuminating these complex relationships will uncover new avenues for developing more effective treatments for cSCC.

Evaluation of Skin Wound Healing with Biosheets Containing Somatic Stem Cells in a Dog Model: A Pilot Study

The administration of mesenchymal stem cells (MSCs) has a positive effect on wound healing; however, the lack of adequate MSC engraftment at the wound site is a major limiting factor in current MSC-based therapies. In this study, a biosheet prepared using in-body tissue architecture (iBTA) was used as a material to address these problems. This study aimed to assess and evaluate whether biosheets containing somatic stem cells would affect the wound healing process in dogs. Biosheets were prepared by subcutaneously embedding molds in beagles. These were then evaluated grossly and histologically, and the mRNA expression of inflammatory cytokines, interleukins, and Nanog was examined in some biosheets. Skin defects were created on the skin of the beagles to which the biosheets were applied. The wound healing processes of the biosheet and control (no biosheet application) groups were compared for 8 weeks. Nanog mRNA was expressed in the biosheets, and SSEA4/CD105 positive cells were observed histologically. Although the wound contraction rates differed significantly in the first week, the biosheet group tended to heal faster than the control group. This study revealed that biosheets containing somatic stem cells may have a positive effect on wound healing.

The future of diabetic wound healing: unveiling the potential of mesenchymal stem cell and exosomes therapy

Diabetes mellitus (DM) is a significant public health problem and is one of the most challenging medical conditions worldwide. It is the severe complications that make this disease more intricate. A diabetic wound is one of these complications. Patients with diabetes are at higher risk of developing diabetic foot ulcers (DFU). Due to the ineffectiveness of Conventional treatments, growth in limb amputation, morbidity, and mortality have been recognized, which indicates the need for additional treatment. Mesenchymal stem cells (MSCs) can significantly improve wound healing. However, there are some risks related to stem cell therapy. Exosome therapy is a new treatment option for diabetic wounds that has shown promising results. However, an even more advanced form called cell-free therapy using exosomes has emerged. This upgraded version of stem cell therapy offers improved efficacy and eliminates the risk of cancer progression. Exosome therapy promotes wound healing from multiple angles, unlike traditional methods that primarily rely on the body's self-healing ability and only provide wound protection. Therefore, exosome therapy has the potential to replace conventional treatments effectively. However, further research is necessary to distinguish the optimal type of stem cells for therapy, ensure their safety, establish appropriate dosing, and identify the best management trail. The present study focused on the current literature on diabetic wound ulcers, their treatment, and mesenchymal stem cell and exosome therapy potential in DFU.

Bone-nerve crosstalk: a new state for neuralizing bone tissue engineering-A mini review

Neuro bone tissue engineering is a multidisciplinary field that combines both principles of neurobiology and bone tissue engineering to develop innovative strategies for repairing and regenerating injured bone tissues. Despite the fact that regeneration and development are considered two distinct biological processes, yet regeneration can be considered the reactivation of development in later life stages to restore missing tissues. It is noteworthy that the regeneration capabilities are distinct and vary from one organism to another (teleost fishes, hydra, humans), or even in the same organism can vary dependent on the injured tissue itself (Human central nervous system vs. peripheral nervous system). The skeletal tissue is highly innervated, peripheral nervous system plays a role in conveying the signals and connecting the central nervous system with the peripheral organs, moreover it has been shown that they play an important role in tissue regeneration. Their regeneration role is conveyed by the different cells' resident in it and in its endoneurium (fibroblasts, microphages, vasculature associated cells, and Schwann cells) these cells secrete various growth factors (NGF, BDNF, GDNF, NT-3, and bFGF) that contribute to the regenerative phenotype. The peripheral nervous system and central nervous system synchronize together in regulating bone homeostasis and regeneration through neurogenic factors and neural circuits. Receptors of important central nervous system peptides such as Serotonin, Leptin, Semaphorins, and BDNF are expressed in bone tissue playing a role in bone homeostasis, metabolism and regeneration. This review will highlight the crosstalk between peripheral nerves and bone in the developmental stages as well as in regeneration and different neuro-bone tissue engineering strategies for repairing severe bone injuries.

Activation of BMP4/SMAD pathway by HIF-1α in hypoxic environment promotes osteogenic differentiation of BMSCs and leads to ectopic bone formation

OBJECTIVE

Heterotopic ossification (HO), also known as ossifying myositis, is a condition that produces abnormal bone and cartilage tissue in the soft tissues. Hypoxia inducible factor lα (HIF-lα) regulates the expression of various genes, which is closely related to the promotion of bone formation, and Drosophila mothers against decapentaplegic protein (SMAD) mediates the signal transduction in the Bone morphogenetic protein (BMP) signaling pathway, which affects the function of osteoblasts and osteoclasts, and thus plays a key role in the regulation of bone remodeling. We aimed to investigate the mechanism by which HIF-1α induces osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) in a hypoxic environment.

METHODS

A cellular hypoxia model was constructed to verify the expression of HIF-1α, while alizarin red staining was performed to observe the osteogenic differentiation ability of bone marrow mesenchymal stem cells (BMSCs). Alizarin red staining was used to analyze the late mineralization ability of the cells. Western blot analysis was performed to analyze the expression levels of osteogenesis-related factors OCN, OPN proteins as well as the pathway proteins BMP4, p-Smad1/5/8, and Smad1. We also constructed a rat model of ectopic bone formation, observed ectopic ossification by X-ray, and verified the success of the rat model by ELISA of HIF-1α. HE staining was used to observe the matrix and trabecular structure of bone, and Masson staining was used to observe the collagen and trabecular structure of bone. Immunohistochemistry analyzed the expression of OCN and OPN in ectopic bone tissues, and WB analyzed the expression of pathway proteins BMP4, p-Smad1/5/8 and Smad1 in ectopic bone tissues to verify the signaling pathway of ectopic bone formation.

RESULTS

Our results indicate that hypoxic environment upregulates HIF-1a expression and activates BMP4/SMAD signaling pathway. This led to an increase in ALP content and enhanced expression of the osteogenesis-related factors OCN and OPN, resulting in enhanced osteogenic differentiation of BMSCs. The results of our in vivo experiments showed that rats inoculated with BMSCs overexpressing HIF-1α showed bony structures in tendon tissues, enhanced expression of the bone signaling pathways BMP4 and p-Smad1/5/8, and enhanced expression levels of the osteogenic-related factors OCN and OPN, resulting in the formation of ectopic bone.

CONCLUSIONS

These data further suggest a novel mechanistic view that hypoxic bone marrow BMSCs activate the BMP4/SMAD pathway by up-regulating the expression level of HIF-1α, thereby promoting the secretion of osteogenic factors leading to ectopic bone formation.

Mesenchymal stem cells for cartilage regeneration: Insights into molecular mechanism and therapeutic strategies

The use of mesenchymal stem cells (MSCs) in cartilage regeneration has gained significant attention in regenerative medicine. This paper reviews the molecular mechanisms underlying MSC-based cartilage regeneration and explores various therapeutic strategies to enhance the efficacy of MSCs in this context. MSCs exhibit multipotent capabilities and can differentiate into various cell lineages under specific microenvironmental cues. Chondrogenic differentiation, a complex process involving signaling pathways, transcription factors, and growth factors, plays a pivotal role in the successful regeneration of cartilage tissue. The chondrogenic differentiation of MSCs is tightly regulated by growth factors and signaling pathways such as TGF-β, BMP, Wnt/β-catenin, RhoA/ROCK, NOTCH, and IHH (Indian hedgehog). Understanding the intricate balance between these pathways is crucial for directing lineage-specific differentiation and preventing undesirable chondrocyte hypertrophy. Additionally, paracrine effects of MSCs, mediated by the secretion of bioactive factors, contribute significantly to immunomodulation, recruitment of endogenous stem cells, and maintenance of chondrocyte phenotype. Pre-treatment strategies utilized to potentiate MSCs, such as hypoxic conditions, low-intensity ultrasound, kartogenin treatment, and gene editing, are also discussed for their potential to enhance MSC survival, differentiation, and paracrine effects. In conclusion, this paper provides a comprehensive overview of the molecular mechanisms involved in MSC-based cartilage regeneration and outlines promising therapeutic strategies. The insights presented contribute to the ongoing efforts in optimizing MSC-based therapies for effective cartilage repair.

Transcriptomic analysis reveals the anti-cancer effect of gestational mesenchymal stem cell secretome

The environment created during embryogenesis contributes to reducing aberrations that drive structural malformations and tumorigenesis. In this study, we investigate the anti-cancer effect of mesenchymal stem cells (MSCs) derived from 2 different gestational tissues, the amniotic fluid (AF) and the chorionic villi (CV), with emphasis on their secretome. Transcriptomic analysis was performed on patient-derived AF- and CV-MSCs collected during prenatal diagnosis and identified both mRNAs and lncRNAs, involved in tissue homeostasis and inhibiting biological processes associated with the etiology of aggressive cancers while regulating immune pathways shown to be important in chronic disorders. Secretome enrichment analysis also identified soluble moieties involved in target cell regulation, tissue homeostasis, and cancer cell inhibition through the highlighted Wnt, TNF, and TGF-β signaling pathways. Transcriptomic data were experimentally confirmed through in vitro assays, by evaluating the anti-cancer effect of the media conditioned by AF- and CV-MSCs and the exosomes derived from them on ovarian cancer cells, revealing inhibitory effects in 2D (by reducing cell viability and inducing apoptosis) and in 3D conditions (by negatively interfering with spheroid formation). These data provide molecular insights into the potential role of gestational tissues-derived MSCs as source of anti-cancer factors, paving the way for the development of therapeutics to create a pro-regenerative environment for tissue restoration following injury, disease, or against degenerative disorders.

Hyaluronic acid stimulation of stem cells for cardiac repair: a cell-free strategy for myocardial infarct

BACKGROUND

Myocardial infarction (MI), a representative form of ischemic heart disease, remains a huge burden worldwide. This study aimed to explore whether extracellular vesicles (EVs) secreted from hyaluronic acid (HA)-primed induced mesenchymal stem cells (HA-iMSC-EVs) could enhance the cardiac repair after MI.

RESULTS

HA-iMSC-EVs showed typical characteristics for EVs such as morphology, size, and marker proteins expression. Compared with iMSC-EVs, HA-iMSC-EVs showed enhanced tube formation and survival against oxidative stress in endothelial cells, while reduced reactive oxygen species (ROS) generation in cardiomyocytes. In THP-1 macrophages, both types of EVs markedly reduced the expression of pro-inflammatory signaling players, whereas HA-iMSC-EVs were more potent in augmenting anti-inflammatory markers. A significant decrease of inflammasome proteins was observed in HA-iMSC-EV-treated THP-1. Further, phospho-SMAD2 as well as fibrosis markers in TGF-β1-stimulated cardiomyocytes were reduced in HA-iMSC-EVs treatment. Proteomic data showed that HA-iMSC-EVs were enriched with multiple pathways including immunity, extracellular matrix organization, angiogenesis, and cell cycle. The localization of HA-iMSC-EVs in myocardium was confirmed after delivery by either intravenous or intramyocardial route, with the latter increased intensity. Echocardiography revealed that intramyocardial HA-iMSC-EVs injections improved cardiac function and reduced adverse cardiac remodeling and necrotic size in MI heart. Histologically, MI hearts receiving HA-iMSC-EVs had increased capillary density and viable myocardium, while showed reduced fibrosis.

CONCLUSIONS

Our results suggest that HA-iMSC-EVs improve cardiac function by augmenting vessel growth, while reducing ROS generation, inflammation, and fibrosis in MI heart.

The biological characteristics of chicken embryo mesenchymal stem cells isolated from chorioallantoic membrane

Mesenchymal stem cells (MSCs) derived from fetal membranes (FMs) have the potential to exhibit immunosuppression, improve blood flow, and increase capillary density during transplantation. In the field of medicine, opening up new avenues for disease treatment. Chicken embryo chorioallantoic membrane (CAM), as an important component of avian species FM structure, has become a stable tissue engineering material in vivo angiogenesis, drug delivery, and toxicology studies. Although it has been confirmed that chorionic mesenchymal stem cells (Ch-MSCs) can be isolated from the outer chorionic layer of FM, little is known about the biological characteristics of MSCs derived from chorionic mesodermal matrix of chicken embryos. Therefore, we evaluated the characteristics of MSCs isolated from chorionic tissues of chicken embryos, including cell proliferation ability, stem cell surface antigen, genetic stability, and in vitro differentiation potential. Ch-MSCs exhibited a broad spindle shaped appearance and could stably maintain diploid karyotype proliferation to passage 15 in vitro. Spindle cells were positive for multifunctional markers of MSCs (CD29, CD44, CD73, CD90, CD105, CD166, OCT4, and NANOG), while hematopoietic cell surface marker CD34, panleukocyte marker CD45, and epithelial cell marker CK19 were negative. In addition, chicken Ch-MSC was induced to differentiate into four types of mesodermal cells in vitro, including osteoblasts, chondrocytes, adipocytes, and myoblasts. Therefore, the differentiation potential of chicken Ch-MSC in vitro may have great potential in tissue engineering. In conclusion, chicken Ch-MSCs may be an excellent model cell for stem cell regenerative medicine and chorionic tissue engineering.

Immunomodulatory Strategies for Cartilage Regeneration in Osteoarthritis

Osteoarthritis (OA) is the most prevalent musculoskeletal disorder and a leading cause of disability globally. Although many efforts have been made to treat this condition, current tissue engineering (TE) and regenerative medicine strategies fail to address the inflammatory tissue environment that leads to the rapid progression of the disease and prevents cartilage tissue formation. First, this review addresses in detail the current anti-inflammatory therapies for OA with a special emphasis on pharmacological approaches, gene therapy, and mesenchymal stromal cell (MSC) intra-articular administration, and discusses the reasons behind the limited clinical success of these approaches at enabling cartilage regeneration. Then, we analyze the state-of-the-art TE strategies and how they can be improved by incorporating immunomodulatory capabilities such as the optimization of biomaterial composition, porosity and geometry, and the loading of anti-inflammatory molecules within an engineered structure. Finally, the review discusses the future directions for the new generation of TE strategies for OA treatment, specifically focusing on the spatiotemporal modulation of anti-inflammatory agent presentation to allow for tailored patient-specific therapies. Impact statement Osteoarthritis (OA) is a prevalent and debilitating musculoskeletal disorder affecting millions worldwide. Despite significant advancements in regenerative medicine and tissue engineering (TE), mitigating inflammation while simultaneously promoting cartilage tissue regeneration in OA remains elusive. In this review article, we discuss current anti-inflammatory therapies and explore their potential synergy with cutting-edge cartilage TE strategies, with a special focus on novel spatiotemporal and patient-specific anti-inflammatory strategies.

BMSC-derived Exosomes Ameliorate Peritoneal Dialysis-associated Peritoneal Fibrosis via the Mir-27a-3p/TP53 Pathway

OBJECTIVE

Peritoneal fibrosis (PF) is the main cause of declining efficiency and ultrafiltration failure of the peritoneum, which restricts the long-term application of peritoneal dialysis (PD). This study aimed to investigate the therapeutic effects and mechanisms of bone marrow mesenchymal stem cells-derived exosomes (BMSC-Exos) on PF in response to PD.

METHODS

Small RNA sequencing analysis of BMSC-Exos was performed by second-generation sequencing. C57BL/6J mice were infused with 4.25% glucose-based peritoneal dialysis fluid (PDF) for 6 consecutive weeks to establish a PF model. A total of 36 mice were randomly divided into 6 groups: control group, 1.5% PDF group, 2.5% PDF group, 4.25% PDF group, BMSC-Exos treatment group, and BMSC-Exos+TP53 treatment group. Reverse transcription quantitative polymerase chain reaction (RT-qPCR) was performed to measure the expression level of miR-27a-3p in BMSC-Exos and peritoneum of mice treated with different concentrations of PDF. HE and Masson staining were performed to evaluate the extent of PF. The therapeutic potential of BMSC-Exos for PF was examined through pathological examination, RT-qPCR, Western blotting, and peritoneal function analyses. Epithelial-mesenchymal transition (EMT) of HMrSV5 was induced with 4.25% PDF. Cells were divided into control group, 4.25% PDF group, BMSC-Exos treatment group, and BMSC-Exos+TP53 treatment group. Cell Counting Kit-8 assay was used to measure cell viability, and transwell migration assay was used to verify the capacity of BMSC-Exos to inhibit EMT in HMrSV5 cells.

RESULTS

Small RNA sequencing analysis showed that miR-27a-3p was highly expressed in BMSC-derived exosomes compared to BMSCs. The RT-qPCR results showed that the expression of miR-27a-3p was upregulated in BMSC-Exos, but decreased in PD mice. We found that PF was glucose concentration-dependently enhanced in the peritoneum of the PD mice. Compared with the control mice, the PD mice showed high solute transport and decreased ultrafiltration volume as well as an obvious fibroproliferative response, with markedly increased peritoneal thickness and higher expression of α-SMA, collagen-I, fibronectin, and ECM1. The mice with PD showed decreased miR-27a-3p. Peritoneal structural and functional damage was significantly attenuated after BMSC-Exos treatment, while PF and mesothelial damage were significantly ameliorated. Additionally, markers of fibrosis (α-SMA, collagen-I, fibronectin, ECM1) and profibrotic cytokines (TGF-β1, PDGF) were downregulated at the mRNA and protein levels after BMSC-Exos treatment. In HMrSV5 cells, BMSC-Exos reversed the decrease in cell viability and the increase in cell migratory capacity caused by high-glucose PDF. Western blotting and RT-qPCR analysis revealed that BMSC-Exos treatment resulted in increased expression of E-cadherin (epithelial marker) and decreased expression of α-SMA, Snail, and vimentin (mesenchymal markers) compared to those of the 4.25% PDF-treated cells. Importantly, a dual-luciferase reporter assay showed that TP53 was a target gene of miR-27a-3p. TP53 overexpression significantly reversed the decreases in PF and EMT progression induced by BMSC-Exos.

CONCLUSION

The present results demonstrate that BMSC-Exos showed an obvious protective effect on PD-related PF and suggest that BMSC-derived exosomal miR-27a-3p may exert its inhibitory effect on PF and EMT progression by targeting TP53.

Therapeutic effect and study of human umbilical cord blood mononuclear cells in patients with ischaemic bowel disease

Ischaemic bowel disease (ICBD) is a group of intestinal ischaemia syndromes caused by various aetiologies of reduced intestinal blood flow or vascular occlusion. ICBD can present as abdominal pain, bloody stool, and diarrhoea. This disease often occurs in middle-aged and elderly individuals with cardiovascular and cerebrovascular diseases. The incidence of ischaemic bowel disease has been increasing for decades, and it is difficult to diagnose, resulting in rapid disease progression and a high mortality rate. Therefore, fully understanding this disease, improving the diagnosis rate of this disease, and finding appropriate treatment methods are urgently needed to improve the condition and prognosis of patients. Umbilical cord blood stem cells are accessible, have weak immunogenicity, and have various biological functions, such as angiogenesis, inflammation and immune regulation. Many studies have confirmed that cord blood stem cells can relieve ischaemia, and these cells have attracted tremendous amounts of attention in regenerative medicine in recent years. In this paper, we discuss the clinical characteristics of ICBD, analyse the characteristics of human umbilical cord blood mononuclear cells (HUCB-MNCs), and use its to treat ischaemic bowel disease. Additionally, we compare the clinical manifestations and related indicators before and after treatment to evaluate the efficacy and safety of these methods.

Immunomodulatory hydrogels for skin wound healing: cellular targets and design strategy

Skin wounds significantly impact the global health care system and represent a significant burden on the economy and society due to their complicated dynamic healing processes, wherein a series of immune events are required to coordinate normal and sequential healing phases, involving multiple immunoregulatory cells such as neutrophils, macrophages, keratinocytes, and fibroblasts, since dysfunction of these cells may impede skin wound healing presenting persisting inflammation, impaired vascularization, and excessive collagen deposition. Therefore, cellular target-based immunomodulation is promising to promote wound healing as cells are the smallest unit of life in immune response. Recently, immunomodulatory hydrogels have become an attractive avenue to promote skin wound healing. However, a detailed and comprehensive review of cellular targets and related hydrogel design strategies remains lacking. In this review, the roles of the main immunoregulatory cells participating in skin wound healing are first discussed, and then we highlight the cellular targets and state-of-the-art design strategies for immunomodulatory hydrogels based on immunoregulatory cells that cover defect, infected, diabetic, burn and tumor wounds and related scar healing. Finally, we discuss the barriers that need to be addressed and future prospects to boost the development and prosperity of immunomodulatory hydrogels.

Therapeutic gene delivery by mesenchymal stem cell for brain ischemia damage: Focus on molecular mechanisms in ischemic stroke

Cerebral ischemic damage is prevalent and the second highest cause of death globally across patient populations; it is as a substantial reason of morbidity and mortality. Mesenchymal stromal cells (MSCs) have garnered significant interest as a potential treatment for cerebral ischemic damage, as shown in ischemic stroke, because of their potent intrinsic features, which include self-regeneration, immunomodulation, and multi-potency. Additionally, MSCs are easily obtained, isolated, and cultured. Despite this, there are a number of obstacles that hinder the effectiveness of MSC-based treatment, such as adverse microenvironmental conditions both in vivo and in vitro. To overcome these obstacles, the naïve MSC has undergone a number of modification processes to enhance its innate therapeutic qualities. Genetic modification and preconditioning modification (with medications, growth factors, and other substances) are the two main categories into which these modification techniques can be separated. This field has advanced significantly and is still attracting attention and innovation. We examine these cutting-edge methods for preserving and even improving the natural biological functions and therapeutic potential of MSCs in relation to adhesion, migration, homing to the target site, survival, and delayed premature senescence. We address the use of genetically altered MSC in stroke-induced damage. Future strategies for improving the therapeutic result and addressing the difficulties associated with MSC modification are also discussed.

Bone tissue regeneration by 58S bioactive glass scaffolds containing exosome: an in vivo study

Exosomes, the naturally secreted nanocarriers of cells, have recently been demonstrated to have therapeutic benefits in a variety of disease models where parent cells are not present. However, the use of exosomes in bone defect regeneration has been unusual, and little is documented about the underlying processes. In recent study we produced and characterized exosomes derived human endometrial mesenchymal stem stromal cells and 58S bioactive glass scaffolds; in following, in this research exosome loaded scaffolds synthetized and release of exosome, porosity and bioactivity of them were assessed. More over the effect of scaffolds on repair of critical-size bone defects in rat's calvaria was evaluated by histological examination and micro computed tomography (µ CT). The findings confirmed that constructed porous scaffolds consistently release exosomes; additionally, in vivo findings including Hematoxilin & Eosin staining, Immunohistochemistry, Masson's trichrome, histomorphometric analysis, and µ CT clarified that our implant has osteogenic properties. We discovered that Exo-treated scaffolds might promote osteogenesis especially compared to pure scaffolds, indicating that produced scaffolds containing exosomes could be a potential replacement in bone tissue engineering.

The Effect of Fat Grafting on Scars Hyperpigmentation: A Systematic Review and Meta-Analysis

BACKGROUND

Hyperpigmented scars, particularly in exposed body areas, can be difficult to conceal and may evoke psychological distress. While the precise causes of scar dyschromia are not fully understood, alterations in melanogenic activity appear to hold more significance than changes in melanocyte quantity. Current treatments encompass laser interventions. However, it is essential to consider their costs and potential complications in relation to their limited proven effectiveness. Fat grafting has gained interest as a scar modulation technique due to its regenerative properties, and its efficacy in reducing scar hyperpigmentation is currently under investigation.

METHODS

A systematic review and meta-analysis was reported according to PRISMA guidelines. PubMed, Embase, and Cochrane Library databases were accessed. PROSPERO registration number is CRD42023457778. The primary outcome was a change in scar pigmentation after fat grafting. Pigmentation changes after fat grafting were calculated using the standardized mean difference (SMD) between baseline and postoperative scores according to POSAS and VSS scales. Bias assessment was conducted according to the National Institute for Health and Clinical Excellence quality assessment tool.

RESULTS

A total of 8 articles meeting inclusion and exclusion criteria were identified, involving 323 patients with hyperpigmented scars treated with fat grafting. A significant difference in scar pigmentation was noted after treatment with fat grafting according to observers' ratings, with a SMD of - 1.09 [95% CI: - 1.32; - 0.85], p<0.01. The SMD for patient-reported scar pigmentation after treatment with fat grafting was - 0.99 [96% CI: - 1.31; - 0.66], p<0.01. Four studies provided objective measurements of melanin changes after fat grafting and revealed inconsistent findings compared to subjective observations.

CONCLUSIONS

Fat grafting shows promise in ameliorating hyperpigmented scars based on subjective assessments, but further corroborating evidence from objective measures is required.

LEVEL OF EVIDENCE IV

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

The therapeutic effect of MSCs and their extracellular vesicles on neuroblastoma

Neuroblastoma is a common inflammatory-related cancer during infancy. Standard treatment modalities including surgical interventions, high-dose chemotherapy, radiotherapy, and immunotherapy are not able to increase survival rate and reduce tumor relapse in high-risk patients. Mesenchymal stem cells (MSCs) are known for their tumor-targeting and immunomodulating properties. MSCs could be engineered to express anticancer agents (i.e., growth factors, cytokines, pro-apoptotic agents) or deliver oncolytic viruses in the tumor microenvironment. As many functions of MSCs are mediated through their secretome, researchers have tried to use extracellular vesicles (EVs) from MSCs for targeted therapy of neuroblastoma. Here, we reviewed the studies to figure out whether the use of MSCs could be worthwhile in neuroblastoma therapy or not. Native MSCs have shown a promoting or inhibiting role in cancers including neuroblastoma. Therefore, MSCs are proposed as a vehicle to deliver anticancer agents such as oncolytic viruses to the neuroblastoma tumor microenvironment. Although modified MSCs or their EVs have been shown to suppress the tumorigenesis of neuroblastoma, further pre-clinical and clinical studies are required to come to a conclusion.

Mesenchymal Stem Cells from the Deciduous Tooth Pulp Lose their Ability to Suppress the Differentiation of Dendritic Cells during Long-Term Culturing

A culture of cells expressing markers of mesenchymal stem cells (MSC) (CD73, CD90, CD44, CD29, and CD49b), but not hematopoietic cell markers, and capable of multilineage differentiation was isolated from the deciduous tooth pulp. Co-culturing with immature dendritic cells in the presence of LPS did not reveal an ability of the MSC to suppress the maturation of dendritic cells. On the contrary, co-culturing of MSC with monocytes in the presence of granulocyte-macrophage CSF and IL-4 led to complete suppression of monocyte differentiation into dendritic cells. However, long-term culturing of MSC from dental pulp showed that by the passage 11, they almost completely lose their suppressor ability. These results indicate that the immunological properties of MSC can change during culturing without changing their phenotypic markers. This should be taken into account when creating biomedical cell products.

MiR-145-5p overexpression rejuvenates aged adipose stem cells and accelerates wound healing

Adipose-derived stem cells (ADSCs) have been widely applied in translational and regenerative medicine. During aging, there is a recognized functional decline in ADSCs, which compromises their therapeutic effectiveness. Currently, the mechanisms of aging-induced stem cell dysfunction remain unclear, hence there is a need to elucidate these mechanisms and propose strategies for reversing this functional impairment. In this study, we found that ADSCs isolated from old donors (O-ADSCs) presented inferior phenotypes and decreased miR-145-5p levels compared to those from young donors (Y-ADSCs). To interrogate the role of miR-145-5p in ADSCs, gain- and loss-of-function assays were performed. The results indicated that miR-145-5p overexpression in O-ADSCs promoted cellular proliferation and migration, while reducing cell senescence. Further study demonstrated that miR-145-5p could regulate ADSCs function by targeting bone morphogenetic protein binding endothelial cell precursor-derived regulator (BMPER), which is a crucial modulator in angiogenesis. Moreover, in vivo experiments showed that miR-145-5p-overexpressing O-ADSCs accelerated wound healing by promoting wound re-epithelialization and angiogenesis. Collectively, this study indicates that miR-145-5p works as a positive regulator for optimizing O-ADSCs function, and may be a novel therapeutic target for restoring aging-associated impairments in stem cell function.

A programmable arthritis-specific receptor for guided articular cartilage regenerative medicine

Objective

Investigational cell therapies have been developed as disease-modifying agents for the treatment of osteoarthritis (OA), including those that inducibly respond to inflammatory factors driving OA progression. However, dysregulated inflammatory cascades do not specifically signify the presence of OA. Here, we deploy a synthetic receptor platform that regulates cell behaviors in an arthritis-specific fashion to confine transgene expression to sites characterized by cartilage degeneration.

Methods

An scFv specific for type II collagen (CII) was used to produce a synthetic Notch (synNotch) receptor that enables "CII-synNotch" mesenchymal stromal cells (MSCs) to recognize CII fibers exposed in damaged cartilage. Engineered cell activation by both CII-treated culture surfaces and on primary tissue samples was measured via inducible reporter transgene expression. TGFβ3-expressing cells were assessed for cartilage anabolic gene expression via qRT-PCR. In a co-culture with CII-synNotch MSCs engineered to express IL-1Ra, ATDC5 chondrocytes were stimulated with IL-1α, and inflammatory responses of ATDC5s were profiled via qRT-PCR and an NF-κB reporter assay.

Results

CII-synNotch MSCs are highly responsive to CII, displaying activation ranges over 40-fold in response to physiologic CII inputs. CII-synNotch cells exhibit the capacity to distinguish between healthy and damaged cartilage tissue and constrain transgene expression to regions of exposed CII fibers. Receptor-regulated TGFβ3 expression resulted in upregulation of Acan and Col2a1 in MSCs, and inducible IL-1Ra expression by engineered CII-synNotch MSCs reduced pro-inflammatory gene expression in chondrocytes.

Conclusion

This work demonstrates proof-of-concept that the synNotch platform guides MSCs for spatially regulated, disease-dependent delivery of OA-relevant biologic drugs.

In vitro characterization of 3D culture-based differentiation of human liver stem cells

Introduction: The lack of functional hepatocytes poses a significant challenge for drug safety testing and therapeutic applications due to the inability of mature hepatocytes to expand and their tendency to lose functionality in vitro. Previous studies have demonstrated the potential of Human Liver Stem Cells (HLSCs) to differentiate into hepatocyte-like cells within an in vitro rotary cell culture system, guided by a combination of growth factors and molecules known to regulate hepatocyte maturation. In this study, we employed a matrix multi-assay approach to comprehensively characterize HLSC differentiation. Methods: We evaluated the expression of hepatic markers using qRT-PCR, immunofluorescence, and Western blot analysis. Additionally, we measured urea and FVIII secretion into the supernatant and developed an updated indocyanine green in vitro assay to assess hepatocyte functionality. Results: Molecular analyses of differentiated HLSC aggregates revealed significant upregulation of hepatic genes, including CYP450, urea cycle enzymes, and uptake transporters exclusively expressed on the sinusoidal side of mature hepatocytes, evident as early as 1 day post-differentiation. Interestingly, HLSCs transiently upregulated stem cell markers during differentiation, followed by downregulation after 7 days. Furthermore, differentiated aggregates demonstrated the ability to release urea and FVIII into the supernatant as early as the first 24 h, with accumulation over time. Discussion: These findings suggest that a 3D rotation culture system may facilitate rapid hepatic differentiation of HLSCs. Despite the limitations of this rotary culture system, its unique advantages hold promise for characterizing HLSC GMP batches for clinical applications.

Sorting Technology for Mesenchymal Stem Cells from a Single Tissue Source

Mesenchymal stem cells (MSCs) are adult stem cells that can be obtained, enriched and proliferated in vitro. They owned enormous potential in fields like regenerative medicine, tissue engineering and immunomodulation. However, though isolated from the same origin, MSCs are still essentially heterogeneous cell populations with different phenotypes and functions. This heterogeneity of MSCs significantly affects their therapeutic efficacy and brings obstacles to scientific research. Thus, reliable sorting technology which can isolate or purify MSC subpopulations with various potential and differentiation pathways is urgently needed. This review summarized principles, application status and clinical implications for these sorting methods, aiming at improving the understanding of MSC heterogeneity as well as providing fresh perspectives for subsequent clinical applications.

Secretome of adipose derived-mesenchymal stem cells reduces the Vibrio cholerae attachment to Caco-2 cells and subsequent inflammatory responses

Background and Objectives

Mesenchymal Stem Cells (MSCs) can repair gastrointestinal tract damage. The Secretome of MSCs has a high capacity to inhibit bacterial colonization and the subsequent inflammatory responses of Vibrio cholerae.

Materials and Methods

The Caco-2 cells were treated with adipose-derived MSCs (AD-MSCs) secretome and then infected with V. cholerae. Subsequently, the bacterial attachment and invasion, cholera toxin gene expression, PGE2 and IL-6 secretion, TNF-α, IL-1β, and IL-8 expression, and apoptosis of Caco-2 cells were evaluated.

Results

The secretome of AD-MSCs significantly reduced the V. cholerae attachment and internalization on Caco-2 epithelial cells (P<0.0001). The cholera toxin (Ctx-B) gene expression (FR=4.56 ± 0.66) and PGE2 production (P=0.0007) were also significantly reduced. The production of NO and TNF-α, IL-1β, and IL-8 pro-inflammatory cytokines were significantly (P<0.05) reduced in exposure to the secretome of AD-MSCs. Secretome also improved a significant 81.33% increase in IL-6 production (128.1 ± 37.6 pg/mL) and showed a 12.36% significant decrease in epithelial cell apoptosis (P< 0.0001) after exposure to V. cholerae.

Conclusion

The secretome of AD-MSCs can play a critical role in inhibiting bacterial colonization, and subsequent inflammatory responses, and maintaining the integrity of the epithelial barrier. The secretome may be effective in the prevention of hypovolemic shock.

Umbilical cord MSC-derived exosomes improve alveolar macrophage function and reduce LPS-induced acute lung injury

Acute lung injury (ALI) is a severe condition that can progress to acute respiratory distress syndrome (ARDS), with a high mortality rate. Currently, no specific and compelling drug treatment plan exists. Mesenchymal stem cells (MSCs) have shown promising results in preclinical and clinical studies as a potential treatment for ALI and other lung-related conditions due to their immunomodulatory properties and ability to regenerate various cell types. The present study focuses on analyzing the role of umbilical cord MSC (UC-MSC))-derived exosomes in reducing lipopolysaccharide-induced ALI and investigating the mechanism involved. The study demonstrates that UC-MSC-derived exosomes effectively improved the metabolic function of alveolar macrophages and promoted their shift to an anti-inflammatory phenotype, leading to a reduction in ALI. The findings also suggest that creating three-dimensional microspheres from the MSCs first can enhance the effectiveness of the exosomes. Further research is needed to fully understand the mechanism of action and optimize the therapeutic potential of MSCs and their secretome in ALI and other lung-related conditions.

Effects of royal jelly on the antisenescence, mitochondrial viability and osteogenic differentiation capacity of umbilical cord-derived mesenchymal stem cells

Mesenchymal stem cells (MSCs) are multipotent cells that have the ability to self-renew and regulate paracrine signalling and immune system processes. MSCs have extensive clinical applications in regeneration, functional reconstruction and cellular therapies. However, studies are needed to discover ways to improve the properties of MSCs, such as differentiation, and prevent senescence in culture, which are both very important for cell therapies. Royal jelly (RJ) is a nutritional substance produced by worker bees that contains a substantial amounts of proteins that are beneficial for cell growth and proliferation. RJ is widely used in traditional medicine today, and due to the specific components in its content, it has been reported to have antioxidant, antiproliferative, antimicrobial, neuroprotective, anti-inflammatory, immunomodulatory and anti-ageing properties. In our study, human Wharton's jelly mesenchymal stem cells (WJ-MSCs) derived from umbilical cord matrix were grown in culture medium supplemented with RJ. The control group comprised minimum essential medium (MEM) and 10% foetal bovine serum (FBS); RJ groups were formed using MEM, 10% FBS and 0.075 mg/ml or 0.150 mg/ml RJ. In our study, we evaluated the effect of RJ on WJ-MSC growth by MTT assay, proliferating cell nuclear antigen ELISA, β-galactosidase activity assay, MitoTracker Green staining and differentiation tests in adipogenic, osteogenic and chondrogenic cell lines. It was observed that the number of mitochondria increased, senescence decreased and osteogenic differentiation increased after differentiation induction after the addition of RJ to MSC culture. In general, the results of this study indicate that WJ-MSCs enhance mitochondrial numbers and important cellular activities, such as antisenescence and osteogenic differentiation, and with increasing evidence from further studies, RJ supplementation may be found beneficial for the use of MSCs in bone engineering regenerative medicine or cell therapy.