Current Stem Cell Research & Therapy - Volume 19, Issue 5, 2024

Burn wounds are a major source of morbidity and mortality in both the military and civilian settings. Research about the pathophysiology of thermal injury has revealed possible interventions that can aid this process to reduce scarring and wound contracture. Bone Marrow derived Mesenchymal Stem Cells (BM-MSCs) have been an exciting topic in research for many years. They have been shown to facilitate wound healing and tissue regeneration, two areas that are vital in the healing process, especially in burn wounds. More recently the discovery of Extracellular Vesicles (EVs) has allowed us to further characterize the immunomodulatory roles and understand the cellular pathways implicated in wound healing. The purpose of this review is to discuss the role of EVs in wound healing, and to propose that EVs are the main mechanism that deliver cellular materials to target cells to coordinate wound healing following tissue injury.

Infertility is a major reproductive health issue worldwide. One of the main problems in infertile women is the failure to generate or release a mature egg. Therefore, the development of new technologies for in vitro generation or induction of mature oocytes can improve various ART procedures. Recently, stem cell-based therapy has opened a new window for several pathological complications. Mesenchymal stem cells (MSCs) are multipotent stem cells with the capacity to self-renew and differentiate into the mesodermal lineage. MSCs contain various bioactive molecules which are involved in the regulation of key biological processes. They can secret multiple paracrine factors, such as VEGF, IGF, HGF, EGF, and FGF to stimulate egg maturation. Although MSCs represent a promising source for cell therapy, the potential risk of tumor development reduces their clinical applications. Recent studies have suggested that the supernatant or conditioned medium of MSCs also contains similar components and regulates the oocyte behavior. The MSC-conditioned medium can eliminate the safety concerns associated with MSC transplantation and avoid rejection problems. Although MSC and MSC-CM could improve oocyte quality, ovarian function, and fertility, these improvements have not yet been demonstrated in clinical trials in humans. Hereby, we summarized recent research findings of MSCs-derived conditioned medium in in vitro development of immature oocytes.

The coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus (SARS-CoV-2), was declared a global pandemic in March 2020 and resulted in more than 6 million deaths worldwide to date. Although several vaccines were produced against COVID-19 and many therapeutic protocols were developed for the management of this respiratory infection, COVID-19 pandemic has still remained an unresolved problem with the emergence of new variants of SARS-CoV-2, especially vaccine-resistant variants. Probably, end of the COVID-19 needs effective and certain treatments which were undiscovered to date. According to immunomodulatory and regenerative properties, mesenchymal stem cells (MSCs) have been considered a therapeutic approach to suppressing cytokine storm caused by SARS-CoV-2 and the treatmet of severe COVID-19. Following intravenous (IV) infusion of MSCs, cells entrap in the lung, guard alveolar epithelial cells, suppress pulmonary fibrosis and improve lung dysfunction. The human menstrual blood-derived stem cells (hMenSCs) as a novel source of MSCs are collected by noninvasive, painless, and easy way without ethical issues. MenScs are an abundant and cheap source with a high proliferation rate and differentiation ability into multiple cell lineages. Regarding immunomodulatory and anti-inflammatory properties, regenerative ability and low immunogenicity, these cells exhibit great potential in the treatment of various diseases. Some clinical trial studies have begun using MenSCs to treat severe COVID-19. According to these trials, MenSC therapy showed promising and encouraging results in treating severe COVID-19. We reviewed published clinical trials and summarized the effects of MenSC therapy on severe COVID-19 with a focus on clinical and laboratory data, immune and inflammatory factors and concluded the advantages and possible risks of this procedure.

Today, treatments of cartilage and osteochondral lesions are routine clinical procedures. The avascular and hard-to-self-repair nature of cartilage tissue has posed a clinical challenge for the replacement and reconstruction of damaged cartilage. Treatment of large articular cartilage defects is technically difficult and complex, often accompanied by failure. Articular cartilage cannot repair itself after injury due to a lack of blood vessels, lymph, and nerves. Various treatments for cartilage regeneration have shown encouraging results, but unfortunately, none have been the perfect solution. New minimally invasive and effective techniques are being developed. The development of tissue engineering technology has created hope for articular cartilage reconstruction. This technology mainly supplies stem cells with various sources of pluripotent and mesenchymal stem cells. This article describes the treatments in detail, including types, grades of cartilage lesions, and immune mechanisms in cartilage injuries.

Diabetes mellitus (DM) is a multifaceted pathological condition, which at present is being considered an epidemic disease keeping the rampant rate of its increase in almost all population groups of the world in consideration. Out of the two types of DM described, T1D is characterized as an autoimmune condition that leads to the destruction of pancreatic β-cells by macrophages and T-cells, thereby, adversely affecting the production of insulin. On the other hand, T2D, often caused by insulin resistance, is commonly related to unhealthy habits, and therefore, it can be prevented in most cases. In both of the conditions, high levels of proinflammatory cytokines like IL-6, TNF-α, and INF-ϒ, lead to chronic inflammation, and elevated oxidative stress resulting in apoptosis and destruction of tissues. Although several treatments are available to treat the symptoms, the underlying causes are not well addressed. One of the most promising approaches to tackle the ill effects and the primary causes of DM is mesenchymal stem cell (MSC) therapy. The use of MSC therapy, because of the immunomodulatory and regenerative properties recorded in this type of cells in a number of experiments carried out in animal models and clinical trials of the disease, has reported positive outcomes. This review covers the principal mechanisms of action induced during MSC therapy in reference to the described pathophysiological pathways of both T1D and T2D. In addition, how this therapeutic intervention can counteract the ill effects of this condition leading to the promotion of tissue regeneration has been covered.

Exosomal-microRNAs (Exo-miRNAs) are key regulators of islet cell function, including insulin expression, processing, and secretion. Exo-miRNAs have a significant impact on the outcomes of islet transplantation as biomarkers for evaluating islet cell function and survival. Furthermore, they have been linked to vascular remodeling and immune regulation following islet transplantation. Mesenchymal stem cell-derived exosomes have been shown in preliminary studies to improve islet cell viability and function when injected or transplanted into mice. Overall, Exo-miRNAs have emerged as novel agents for improving islet transplantation success rates. The role of islet-derived Exo-miRNAs and mesenchymal stem cells-derived Exo-miRNAs as biomarkers and immunomodulators in islet regeneration, as well as their role in improving islet cell viability and function in islet transplantation, are discussed in this review.

Ischemic stroke is the leading cause of death and disability worldwide, with increasing incidence and mortality, imposing a significant social and economic burden on patients and their families. However, cerebral vascular occlusion leads to acute loss of neurons and destruction of synaptic structures. The limited treatment options cannot adequately address intra-neuronal mitochondrial dysfunction due to stroke. Therefore, stem cell-derived mitochondria transplantation plays an important role in neuronal protection and recovery after stroke, when combined with the intracranial and extracranial immunoregulatory effects of stem cell therapy, revealing the mechanism of transferred mitochondria in stem cells in protecting neurological function among chronic-phase ischemic stroke by affecting the endogenous apoptotic pathway of neuronal cells. This research elaborated on the mitochondrial dysfunction in neurons after ischemic stroke, followed by human bone marrow mesenchymal stem cells (hBMSC) rescued damaged neurons by mitochondrial transfer through tunneling nanotubes (TNTs), and the immunomodulatory effect of the preferential transfer of stem cells to the spleen when transplanted into the body which created an immune environment for nerve repair, as well as improved neurological recovery after the chronic phase of stroke. This review is expected to provide a novel idea for applying intracranial stem cell transplantation in chronic-phase ischemic stroke treatment.

In this review, we describe a new avenue that involves the therapeutic use of human adipose tissue. In the past two decades, thousands of papers have described the potential clinical use of human fat and adipose tissue. Moreover, mesenchymal stem cells have been a source of great enthusiasm in clinical studies, and these have generated curiosity at academic levels. On the other hand, they have created considerable commercial business opportunities. High expectations have emerged for curing some recalcitrant diseases or reconstructing anatomically defective human body parts, but several concerns have been raised by generating criticism on the clinical practice that have not been substantiated by rigorous scientific evidence. However, in general, the consensus is that human adipose-derived mesenchymal stem cells inhibit the production of inflammatory cytokines and stimulate the production of anti-inflammatory cytokines. Here, we show that the application of a mechanical elliptical force for several minutes to human abdominal fat activates anti-inflammatory properties and gene-related expression. This may pave the way for new unexpected clinical developments.

Alzheimer's disease (AD) is a neurodegenerative disorder accompanied by a reduction in cognition and memory. Till now, there is no definite cure for AD, although, there are treatments available that may improve some symptoms. Currently, in regenerative medicine stem cells are widely used, mainly for treating neurodegenerative diseases. There are numerous forms of stem cells to treat AD aiming at the expansion of the treatment methods for this particular disease. Since 10 years ago, science has gained abundant knowledge to treat AD by understanding the sorts of stem cells, methods, and phasing of injection. Besides, due to the side effects of stem cell therapy like the potentiation for cancer, and as it is hard to follow the cells through the matrix of the brain, researchers have presented a new therapy for AD. They prefer to use conditioned media (CM) that are full of different growth factors, cytokines, chemokines, enzymes, etc. without tumorigenicity or immunogenicity such as stem cells. Another benefit of CM is that CM could be kept in the freezer, easily packaged, and transported, and doesn’t need to fit with the donor. Due to the beneficial effects of CM, in this paper, we intend to evaluate the effects of various types of CM of stem cells on AD.

Critical-sized bone defects are a challenging issue during bone regeneration. Bone tissue engineering is aimed to repair such defects using biomimicking scaffolds and stem cells. Electrospinning allows the fabrication of biocompatible, biodegradable, and strengthened scaffolds for bone regeneration. Natural and synthetic polymers, alone or in combination, have been employed to fabricate scaffolds with appropriate properties for the osteogenic differentiation of stem cells. Dental pulps are rich in stem cells, and dental pulp stem cells (DPSCs) have a high capacity for proliferation, differentiation, immunomodulation, and trophic factor expression. Researchers have tried to enhance osteogenesis through scaffold modification approaches, including incorporation or coating with mineral, inorganic materials, and herbal extract components. Among them, the incorporation of nanofibers with hyaluronic acid (HA) has been widely used to promote osteogenesis. In this review, the electrospun scaffolds and their modifications used in combination with DPSCs for bone regeneration are discussed.

Background: Bisphenol-A (BPA) has a well-proven deleterious effect on the hypothalamicpituitary- gonadal axis. Objectives: The current study investigated the therapeutic potentials of mesenchymal stem cells (MSCs) in a murine model of BPA-induced ovarian damage. Methods: Fifty adult female rats were divided into: Group 1; control group, Group IIa, IIb: rats were given oral gavage of BPA (25 and 50 mg/Kg body weight respectively) on a daily basis for 15 days, and Group IIIa, IIIb; rats were intravenously treated with of MSCs (10⁶ cells) after receiving the last dose of BPA as in group II. Plasma and ovarian tissue levels of Malondialdehyde (MDA) and gonadal axis hormones were assessed. Apoptosis was evaluated by TUNNEL assay and by apoptosis markers (FAS, FASL, Caspase 3, SLTM). A histological examination of ovarian tissue was also conducted. Results: BPA resulted in a significant elevation in plasma levels of LH, FSH, and ovarian tissue levels of MDA and a significant decrease in estradiol and progesterone. All genetic and protein markers of apoptosis were elevated in BPA treated group with decreased oestrogen receptor expression in the ovarian tissue. Increased apoptotic cells were confirmed by TUNEL assay. A high dose of BPA was able to increase the number of atretic follicles in the ovarian tissue whereas the numbers of primordial, primary, secondary and Graafian follicles were decreased. All the laboratory and histological abnormalities were ameliorated by treatment with MSCs. Conclusion: The antioxidant and anti-apoptotic effects of MSCs could possibly explain the ability of this therapeutic modality to ameliorate BPA-induced-ovarian damage.

Background: Hematologic diseases have seriously threatened human health. Although hematopoietic stem cell transplantation (HSCT) is an effective curative option, the complications, especially graft-versus-host disease (GVHD), are a big problem. Methods: TNF-α pretreatment of hematopoietic stem cells. Apoptosis was detected by flow cytometry, Transwell, and wound healing assays were used to assess cell migration and invasion, E-selectin expression was observed by fluorescence imaging, the levels of NO were measured by a kit, the expression of Ecadherin, MMP2, and MMP9 was detected in cells by qRT-PCR, and western blot was used to analyze the expression of E-cadherin, CXCL12, MCP-1, MCP-3, MMP2, and MMP9. Results: TNF-α induces a high apoptosis rate of CD3, CD19, and CD133 and a low apoptosis rate of CD34. The level of Fas and TNF-R1 was significantly high than that of TNF-R2. HSCs treated with TNF- α declined the invasion and migration of HUVECs. E-selectin, MMP2 and MMP9 mRNA levels of HUVECs and MMP2, CXCL12, MCP-1, and MCP-3 were decreased after HSCs-TNF-α treatment, while the E-cadherin mRNA and protein level of HUVECs was enhanced with HSCs-TNF-α treatment. Conclusion: TNF-α pretreated HSCs can lead to reduced levels of migration, adhesion, and chemokines of HUVECs, thereby declining the inflammatory response and GVHD.

Background: Cancer stem cells (CSCs) contribute to metastasis and drug resistance to immunotherapy in lung adenocarcinoma (LUAD), so the stemness evaluation of cancer cells is of great significance. Method: The single-cell RNA sequencing (scRNA-seq) data of the GSE149655 dataset were collected and analyzed. Malignant cells were distinguished by CopyKAT. CytoTRACE score of marker genes in malignant cells was counted by CytoTRACE to construct the stemness score formula. Sample stemness score in TCGA was determined by the formula and divided into high-, medium- and low-stemness score groups. LASSO and COX regression analyses were carried out to screen the key genes related to the prognosis of LUAD from the differentially expressed genes (DEGs) in high- and low-stemness score groups and a risk score model was constructed. Result: Seven types of cells were identified from a total of 4 samples, and 193 marker genes of 3455 malignant cells were identified. There were 1098 DEGs between low- and high-stemness score groups of TCGA, of which CPS1, CENPK, GJB3, and TPSB2 constituted gene signatures. The 4-gene signature could independently evaluate LUAD survival in the training and validation sets and showed an acceptable area under the receiver operator characteristic (ROC) curves (AUCs). Conclusion: This study provides insights into the cellular heterogeneity of LUAD and develops a new cancer stemness evaluation indicator and a 4-gene signature as a potential tool for evaluating the response of LUAD to immune checkpoint blockade (ICB) therapy or antineoplastic therapy.

Background: To investigate the roles of extracellular vesicles (EVs) secreted from bone marrow mesenchymal stem cells (BMSCs) and miR-27 (highly expressed in BMSC EVs) in hepatic ischemia128;’ reperfusion injury (HIRI). Approaches and Results: We constructed a HIRI mouse model and pretreated it with an injection of agomir-miR-27-3p, agomir-NC, BMSC-EVs or control normal PBS into the abdominal cavity. Compared with the HIRI group, HIRI mice preinjected with BMSC-EVs had significantly decreased alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels and alleviated liver necrosis (P<0.05). However, compared with HIRI+NC mice, HIRI+miR-27b mice had significantly increased ALT and AST levels, aggravated liver necrosis, and increased apoptosis-related protein expression (P<0.05). The proliferation and apoptosis of AML-12 cells transfected with miR-27 were significantly higher than the proliferation and apoptosis of AML-12 cells in the mimic NC group (P<0.01) after hypoxia induction. SMAD4 was proven to be a miR-27 target gene. Furthermore, compared to HIRI+NC mice, HIRI+miR-27 mice displayed extremely reduced SMAD4 expression and increased levels of wnt1, β-catenin, c-Myc, and Cyclin D1. Conclusion: Our findings reveal the role and mechanism of miR-27 in HIRI and provide novel insights for the prevention and treatment of HIRI; for example, EVs derived from BMSCs transfected with antimiR- 27 might demonstrate better protection against HIRI.

Aim: This study aimed to identify the molecular type and prognostic model of lung adenocarcinoma (LUAD) based on cancer stem cell-related genes. Studies have shown that cancer stem cells (CSC) are involved in the development, recurrence, metastasis, and drug resistance of tumors. Method: The clinical information and RNA-seq of LUAD were obtained from the TCGA database. scRNA dataset GSE131907 and 5 GSE datasets were downloaded from the GEO database. Molecular subtypes were identified by ConsensusClusterPlus. A CSC-related prognostic signature was then constructed via univariate Cox and LASSO Cox-regression analysis. Result: A scRNA-seq GSE131907 dataset was employed to obtain 11 cell clusters, among which, 173 differentially expressed genes in CSC were identified. Moreover, the CSC score and mRNAsi were higher in tumor samples. 18 of 173 genes were survival time-associated genes in both the TCGA-LUDA dataset and the GSE dataset. Next, two molecular subtypes (namely, CSC1 and CSC2) were identified based on 18 survival-related CSC genes with distinct immune profiles and noticeably different prognoses as well as differences in the sensitivity of chemotherapy drugs. 8 genes were used to build a prognostic model in the TCGA-LUAD dataset. High-risk patients faced worse survival than those with a low risk. The robust predictive ability of the risk score was validated by the time-dependent ROC curve revealed as well as the GSE dataset. TIDE analysis showed a higher sensitivity of patients in the low group to immunotherapy. Conclusion: This study has revealed the effect of CSC on the heterogeneity of LUAD, and created an 8 genes prognosis model that can be potentially valuable for predicting the prognosis of LUAD and response to immunotherapy.