IL-1β-Induced Matrix Metalloprotease-1 Promotes Mesenchymal Stem Cell Migration via PAR1 and G-Protein-Coupled Signaling Pathway

Therapeutic trends of priming mesenchymal stem cells: A bibliometric analysis

Mesenchymal stem cells (MSCs) have gained substantial attention in regenerative medicine due to their multilineage differentiation potential and immunomodulatory capabilities. MSCs have demonstrated therapeutic promise in numerous preclinical and clinical studies across a variety of diseases, including neurodegenerative disorders, cardiovascular diseases, and autoimmune conditions. Recently, priming MSCs has emerged as a novel strategy to enhance their therapeutic efficacy by preconditioning them for optimal survival and function in challenging in vivo environments. This study presented a comprehensive bibliometric analysis of research activity in the field of priming mesenchymal stem cells (MSCs) from 2003 to 2023. Utilizing a dataset of 585 documents, we explored research trends, leading authors and countries, productive journals, and frequently used keywords. We also explored priming strategies to augment the therapeutic efficacy of MSCs. Our findings show increasing research productivity with a peak in 2019, identified the United States as the leading contributor, and highlighted WANG JA as the most prolific author. The most published journal was Stem Cell Research & Therapy. Keyword analysis revealed core research areas emerging hotspots, while coword and cited sources visualizations elucidated the conceptual framework and key information sources. Further studies are crucial to advance the translation of primed MSCs from bench to bedside, potentially revolutionizing the landscape of regenerative medicine.

Mesenchymal stromal cell derived extracellular vesicles as a therapeutic tool: immune regulation, MSC priming, and applications to SLE

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease characterized by a dysfunction of the immune system. Mesenchymal stromal cell (MSCs) derived extracellular vesicles (EVs) are nanometer-sized particles carrying a diverse range of bioactive molecules, such as proteins, miRNAs, and lipids. Despite the methodological disparities, recent works on MSC-EVs have highlighted their broad immunosuppressive effect, thus driving forwards the potential of MSC-EVs in the treatment of chronic diseases. Nonetheless, their mechanism of action is still unclear, and better understanding is needed for clinical application. Therefore, we describe in this review the diverse range of bioactive molecules mediating their immunomodulatory effect, the techniques and possibilities for enhancing their immune activity, and finally the potential application to SLE.

Exosomal Osteoclast-Derived miRNA in Rheumatoid Arthritis: From Their Pathogenesis in Bone Erosion to New Therapeutic Approaches

Rheumatoid arthritis (RA) is an autoimmune disease that causes inflammation, pain, and ultimately, bone erosion of the joints. The causes of this disease are multifactorial, including genetic factors, such as the presence of the human leukocyte antigen (HLA)-DRB1*04 variant, alterations in the microbiota, or immune factors including increased cytotoxic T lymphocytes (CTLs), neutrophils, or elevated M1 macrophages which, taken together, produce high levels of pro-inflammatory cytokines. In this review, we focused on the function exerted by osteoclasts on osteoblasts and other osteoclasts by means of the release of exosomal microRNAs (miRNAs). Based on a thorough revision, we classified these molecules into three categories according to their function: osteoclast inhibitors (miR-23a, miR-29b, and miR-214), osteoblast inhibitors (miR-22-3p, miR-26a, miR-27a, miR-29a, miR-125b, and miR-146a), and osteoblast enhancers (miR-20a, miR-34a, miR-96, miR-106a, miR-142, miR-199a, miR-324, and miR-486b). Finally, we analyzed potential therapeutic targets of these exosomal miRNAs, such as the use of antagomiRs, blockmiRs, agomiRs and competitive endogenous RNAs (ceRNAs), which are already being tested in murine and ex vivo models of RA. These strategies might have an important role in reestablishing the regulation of osteoclast and osteoblast differentiation making progress in the development of personalized medicine.

Characteristics and time points to inhibit ferroptosis in human osteoarthritis

Ferroptosis is a form of cell death that is triggered by iron-dependent lipid peroxidation and is closely associated with osteoarthritis. The primary interventions for inhibiting ferroptosis in osteoarthritis are anti-lipid peroxidation and iron chelation. The objective of our study is to investigate the characteristics of ferroptosis in osteoarthritis and identify the optimal time points for inhibiting ferroptosis to alleviate disease progression. Ferroptosis-related alterations and markers of OA were analyzed in paired intact and damaged cartilages from OA patients by immunofluorescence, qRT-PCR, mitochondrial membrane potential and immunohistochemistry. We also compared Ferroptosis-related alterations in cartilage of mild, moderate, and severe OA (according to the modified Mankin score). In addition, we compared the effect of Fer-1 on ferroptosis and the protection of chondrocytes by detecting markers of both ferroptosis and OA by immunofluorescence, CCK8 and qRT-PCR. Ferroptosis-related alterations (GPX4 downregulation, ACSL4 upregulation, MDA, LPO accumulation, Mitochondrial membrane potential decreased) in the damaged area cartilage were more severe than those in the intact area and increased with the progression of OA. Compared with mild OA group, the activity of chondrocytes treated with Fer-1 (a ferroptosis inhibitor) was increased, mitochondrial function was improved, and ferroptosis was reduced (GPX4 upregulation, SLC7A11 upregulation, ACSL4 downregulation,), and promoted the expression of COL2A1 and inhibited the expression of MMP13. However, these changes were not observed in moderate and severe OA chondrocytes. Ferroptosis occurs in a region-specific manner and is exacerbated with the progression of human OA cartilage degeneration. Inhibition of ferroptosis might had a therapeutic effect on chondrocytes with mild OA but had no significant therapeutic effect on chondrocytes with moderate to severe OA.

IL-1β stimulated human umbilical cord mesenchymal stem cells ameliorate rheumatoid arthritis via inducing apoptosis of fibroblast-like synoviocytes

Rheumatoid arthritis (RA) is characterized by synovial proliferation and lymphocyte accumulation leading to progressive damage of the periarticular bone and the articular cartilage. The hyperplasia of the synovial intima lining mainly consists of fibroblast-like synoviocytes-rheumatoid arthritis (HFLS-RA) which exhibit apoptosis-resistance, hyper-proliferation, and high invasiveness. The therapeutic efficacy of mesenchymal stem cells (MSCs) treatment in RA has been shown to be due to its immuno-regulatory ability. However, the exact factors and mechanisms involved in MSCs treatment in RA remain unclear. In this study, TRAIL receptor-Death receptor 4 (DR4), DR5, and LFA-1 ligand-intercellular adhesion molecule-1 (ICAM-1) were upregulated in IL-1β-stimulated HFLS-RA. We demonstrated that the total cell number of IL-1β-stimulated hUCMSCs adhering to IL-1β-stimulated HFLA-RA increased via LFA-1/ICAM-1 interaction. Direct co-culture of IL-1β-stimulated hUCMSCs with IL-1β-stimulated HFLS-RA increased the apoptosis of HFLS-RA. RA symptoms in the CIA mouse model improved after administration of IL-1β-stimulated hUCMSCs. In conclusion, IL-1β-stimulated hUCMSCs adhering to HFLS-RA occurred via LFA-1/ICAM-1 interaction, apoptosis of HFLS-RA was induced via TRAIL/DR4, DR5 contact, and RA symptoms and inflammation were significantly improved in a CIA mouse model. The results of this study suggest that IL-1β-stimulated hUCMSCs have therapeutic potential in RA treatment.

The Dual Role of Mesenchymal Stem Cells in Cancer Pathophysiology: Pro-Tumorigenic Effects versus Therapeutic Potential

Mesenchymal stem/stromal cells (MSCs) are multipotent cells involved in numerous physiological events, including organogenesis, the maintenance of tissue homeostasis, regeneration, or tissue repair. MSCs are increasingly recognized as playing a major, dual, and complex role in cancer pathophysiology through their ability to limit or promote tumor progression. Indeed, these cells are known to interact with the tumor microenvironment, modulate the behavior of tumor cells, influence their functions, and promote distant metastasis formation through the secretion of mediators, the regulation of cell-cell interactions, and the modulation of the immune response. This dynamic network can lead to the establishment of immunoprivileged tissue niches or the formation of new tumors through the proliferation/differentiation of MSCs into cancer-associated fibroblasts as well as cancer stem cells. However, MSCs exhibit also therapeutic effects including anti-tumor, anti-proliferative, anti-inflammatory, or anti-oxidative effects. The therapeutic interest in MSCs is currently growing, mainly due to their ability to selectively migrate and penetrate tumor sites, which would make them relevant as vectors for advanced therapies. Therefore, this review aims to provide an overview of the double-edged sword implications of MSCs in tumor processes. The therapeutic potential of MSCs will be reviewed in melanoma and lung cancers.

Immunomodulatory Mechanisms and Therapeutic Potential of Mesenchymal Stem Cells

Mesenchymal stem cells (MSCs) are regarded as highly promising cells for allogeneic cell therapy, owing to their multipotent nature and ability to display potent and varied functions in different diseases. The functions of MSCs, including native immunomodulation, high self-renewal characteristic, and secretory and trophic properties, can be employed to improve the immune-modulatory functions in diseases. MSCs impact most immune cells by directly contacting and/or secreting positive microenvironmental factors to influence them. Previous studies have reported that the immunomodulatory role of MSCs is basically dependent on their secretion ability from MSCs. This review discusses the immunomodulatory capabilities of MSCs and the promising strategies to successfully improve the potential utilization of MSCs in clinical research.

Enhancers of mesenchymal stem cell stemness and therapeutic potency

Mesenchymal stem cells (MSCs) are multipotent stromal cells that can differentiate into a range of cell types, including osteoblasts, chondrocytes, myocytes, and adipocytes. Multiple preclinical investigations and clinical trials employed enhanced MSCs-dependent therapies in treatment of inflammatory and degenerative diseases. They have demonstrated considerable and prospective therapeutic potentials even though the large-scale use remains a problem. Several strategies have been used to improve the therapeutic potency of MSCs in cellular therapy. Treatment of MSCs utilizing pharmaceutical compounds, cytokines, growth factors, hormones, and vitamins have shown potential outcomes in boosting MSCs' stemness. In this study, we reviewed the current advances in enhancing techniques that attempt to promote MSCs' therapeutic effectiveness in cellular therapy and stemness in vivo with potential mechanisms and applications.

Specificity protein 1-mediated ACSL4 transcription promoted the osteoarthritis progression through suppressing the ferroptosis of chondrocytes

BACKGROUND

Chondrocytes are the main cell damage type involved in the occurrence and development of osteoarthritis (OA). Ferroptosis has been confirmed to be related to many degenerative diseases. This research aimed to explore the role of Sp1 and ACSL4 in ferroptosis in the IL-1β-treated human chondrocyte cells line (HCCs).

METHODS

The cell viability was detected with CCK8 assay. The ROS, MDA, GSH, and Fe²⁺ levels were assessed with corresponding detecting kits. The Col2a1, Acan, Mmp13, Gpx4 and Tfr1 levels were determined by RT-qPCR assay. Western blot was conducted to evaluate the Acsl4 and Sp1 levels. PI staining was carried out to analyze the cell death. The double luciferase report was conducted to verify the interaction between Acsl4 and Sp1.

RESULTS

The results showed that IL-1β stimulation elevated the LDH release, cell viability, ROS, MDA and Fe²⁺ levels and declined the GSH levels in the HCCs. Additionally, the mRNA levels of Col2a1, Acan, and Gpx4 were prominently decreased, while Mmp13 and Tfr1 were prominently elevated in the IL-1β stimulated HCCs. Furthermore, Acsl4 protein levels were upregulated in the IL-1β-stimulated HCCs. Both Acsl4 knockdown and ferrostatin-1 treatment neutralized the role of IL-1β in the HCCs. What's more, Acsl4 was transcriptionally regulated by Specificity protein 1 (Sp1). Sp1 overexpression enhanced the Acsl4 levels and Sp1 knockdown declined it.

CONCLUSION

Upregulation of Sp1 activates Ascl4 transcription and thus mediates the occurrence of ferroptosis. Hence, Acsl4 may be a therapeutic target for intervention of OA.

Cordycepin-induced Keratinocyte Secretome Promotes Skin Cell Regeneration

BACKGROUND/AIM

Skin regeneration is the intrinsic ability to repair damaged skin tissues to regaining skin well-being. Processes of wound healing, a major part of skin regeneration, involve various types of cells, including keratinocytes and dermal fibroblasts, through their autocrine/paracrine signals. The releasable factors from keratinocytes were reported to influence dermal fibroblasts behavior during wound-healing processes. Here, we developed a strategy to modulate cytokine components and improve the secretome quality of HaCaT cells, a nontumorigenic immortalized keratinocyte cell line, via the treatment of cordycepin, and designated as cordycepin-induced HaCaT secretome (CHS).

MATERIALS AND METHODS

The bioactivities of CHS were investigated in vitro on human dermal fibroblasts (HDF). The effects of CHS on HDF proliferation, reactive oxygen species-scavenging, cell migration, extracellular matrix production and autophagy activation were investigated by 3-(4,5-dimethylthiazol-2yl)-2,5-diphenyl tetrazolium bromide cell viability assay, dichloro-dihydro-fluorescein diacetate, the wound-healing assay, reverse transcription polymerase chain reaction and immunofluorescent microscopy. Finally, Proteome Profiler™ Array was used to determine the composition of the secretome.

RESULTS

CHS induced fibroblast proliferation/migration, reactive oxygen species-scavenging property, regulation of extracellular matrix synthesis, and autophagy activation. Such enhanced bioactivities of CHS were related to the increase of some key cytokines, including C-X-C motif chemokine ligand 1, interleukin 1 receptor A, interleukin 8, macrophage migration-inhibitory factor, and serpin family E member 1.

CONCLUSION

These findings highlight the implications of cordycepin alteration of the cytokine profile of the HaCaT secretome, which represents a novel biosubstance for the development of wound healing and skin regeneration products.

The Role of Mesenchymal Stem Cells and Exosomes in Tumor Development and Targeted Antitumor Therapies

Mesenchymal stem cells (MSCs) can be isolated from various tissues in adults and differentiated into cells of the osteoblasts, adipocytes, chondrocytes, and myocytes. Recruitments of MSCs towards tumors have a crucial contribution to tumor development. However, the role of MSCs in the tumor microenvironment is uncertain. In addition, due to its tropism to the tumor and low immunogenic properties, more and more pieces of evidence indicate that MSCs may be an ideal carrier for antitumor biologics such as cytokines, chemotherapeutic agents, and oncolytic viruses. Here, we review the existing knowledge on the anti- and protumorigenic effect of MSCs and their extracellular vesicles and exosomes, the role of MSCs, and their extracellular vesicles and exosomes as antitumor vectors.

Stem Cells for Cancer Therapy: Translating the Uncertainties and Possibilities of Stem Cell Properties into Opportunities for Effective Cancer Therapy

Cancer recurrence and drug resistance following treatment, as well as metastatic forms of cancer, are trends that are commonly encountered in cancer management. Amidst the growing popularity of personalized medicine and targeted therapy as effective cancer treatment, studies involving the use of stem cells in cancer therapy are gaining ground as promising translational treatment options that are actively pursued by researchers due to their unique tumor-homing activities and anti-cancer properties. Therefore, this review will highlight cancer interactions with commonly studied stem cell types, namely, mesenchymal stroma/stem cells (MSC), induced pluripotent stem cells (iPSC), iPSC-derived MSC (iMSC), and cancer stem cells (CSC). A particular focus will be on the effects of paracrine signaling activities and exosomal miRNA interaction released by MSC and iMSCs within the tumor microenvironment (TME) along with their therapeutic potential as anti-cancer delivery agents. Similarly, the role of exosomal miRNA released by CSCs will be further discussed in the context of its role in cancer recurrence and metastatic spread, which leads to a better understanding of how such exosomal miRNA could be used as potential forms of non-cell-based cancer therapy.

Knockout of integrin β1 in induced pluripotent stem cells accelerates skin-wound healing by promoting cell migration in extracellular matrix

Background

Induced pluripotent stem cells (iPSCs) have the potential to promote wound healing; however, their adhesion to the extracellular matrix (ECM) might decrease iPSC migration, thereby limiting their therapeutic potential. Integrin β1 (Itgb1) is the major integrin subunit that mediates iPSC-ECM adhesion, suggesting that knocking out Itgb1 might be an effective method for enhancing the therapeutic efficacy of iPSCs.

Methods

We knocked out Itgb1 in mouse iPSCs and evaluated its effects on the therapeutic potential of topically applied iPSCs, as well as their underlying in vivo and in vitro mechanisms.

Results

The Itgb1-knockout (Itgb1-KO) did not change iPSC pluripotency, function, or survival in the absence of embedding in an ECM gel but did accelerate wound healing, angiogenesis, blood perfusion, and survival in skin-wound lesions. However, embedding in an ECM gel inhibited the in vivo effects of wild-type iPSCs but not those of Itgb1-knockout iPSCs. Additionally, in vitro results showed that Itgb1-knockout decreased iPSC-ECM adhesion while increasing ECM-crossing migration. Moreover, ECM coating on the culture surface did not change cell survival, regardless of Itgb1 status; however, the in vivo and in vitro functions of both Itgb1-knockout and wild-type iPSCs were not affected by the presence of agarose gel, which does not contain integrin-binding sites. Knockout of Integrin α4 (Itga4) did not change the above-mentioned cellular and therapeutic functions of iPSCs.

Conclusions

Itgb1-knockout increased iPSCs migration and the wound-healing-promoting effect of topically applied iPSCs. These findings suggest the inhibition of Itgb1 expression is a possible strategy for increasing the efficacy of iPSC therapies.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13287-022-03085-7.

PINK1-Dependent Mitophagy Reduced Endothelial Hyperpermeability and Cell Migration Capacity Under Simulated Microgravity

The effect of cardiovascular dysfunction including orthostatic intolerance and disability on physical exercise is one of the health problems induced by long-term spaceflight astronauts face. As an important part of vascular structure, the vascular endothelium, uniquely sensitive to mechanical force, plays a pivotal role in coordinating vascular functions. Our study found that simulated microgravity induced PINK1-dependent mitophagy in human umbilical vein endothelial cells (HUVECs). Here, we explored the underlying mechanism of mitophagy induction. The ER stress induced by proteostasis failure in HUVECs promoted the Ca2+ transfer from ER to mitochondria, resulting in mitochondria Ca2+ overload, decreased mitochondrial membrane potential, mitochondria fission, and accumulation of Parkin and p62 in mitochondria and mitophagy under simulated microgravity. Moreover, we assumed that mitophagy played a vital role in functional changes in endothelial cells under simulated microgravity. Using mdivi-1 and PINK1 knockdown, we found that NLRP3 inflammasome activation was enhanced after mitophagy was inhibited. The NLRP3 inflammasome contributed to endothelial hyperpermeability and cellular migration by releasing IL-1β. Thus, mitophagy inhibited cell migration ability and hyperpermeability in HUVECs exposed to clinostat-simulated microgravity. Collectively, we here clarify the mechanism of mitophagy induction by simulated microgravity in vitro and demonstrate the relationship between mitophagy and vascular endothelial functional changes including cellular migration and permeability. This study deepens the understanding of vascular functional changes under microgravity.

Optimization of the Duration of the Administration of Mesenchymal Stem Cells Wharton’s Jelly to the Level of Matrix Metalloproteinase-1 and Transforming Growth Factor-β in Osteoarthritis Rat Model

BACKGROUND: Mesenchymal Stem Cell Wharton’s Jelly (MSC-WJ) is promising candidates for osteoarthritis (OA) therapy since they have chondrogenic potential and the ability to form the extracellular matrix. AIM: This study aimed to determine the effect of the time giving MSC-WJ on bioactive markers of osteoarthritis. METHODS: The osteoarthritis rat model was treated by intra-articular injection with MSC-WJ and α _MEM as a control. Four and 8 weeks later performed a histological analysis of cartilage and the determination of the levels of Matrix Metalloproteinase-1(MMP-1) and Transforming growth factor β1 (TGF-β1) in serum by ELISA. RESULTS: The results showed that administration of MSC-WJ showed improvement in the histological picture of knee joints in experimental animals characterized by an increase in cartilage thickness on the joint surface. The administration of MSC-WJ showed a tendency to decrease MMP-1 serum levels of OA rats treated for 8 weeks, although statistically did not show a significant difference. Whereas, administration of MSC-WJ showed a decrease in serum levels of TGF-β1 OA rat treated for 8 weeks. CONCLUSION: MSC-WJ can repair damaged knee OA cartilage tissue. The administration of MSC-WJ can reduce serum levels of TGF-β1 OA rats treated for 8 weeks.

Protease Activated Receptors: A Pathway to Boosting Mesenchymal Stromal Cell Therapeutic Efficacy in Acute Respiratory Distress Syndrome?

Acute Respiratory Distress Syndrome is the most common cause of respiratory failure among critically ill patients, and its importance has been heightened during the COVID-19 pandemic. Even with the best supportive care, the mortality rate in the most severe cases is 40–50%, and the only pharmacological agent shown to be of possible benefit has been steroids. Mesenchymal stromal cells (MSCs) have been tested in several pre-clinical models of lung injury and been found to have significant therapeutic benefit related to: (a) potent immunomodulation; (b) secretion of epithelial and endothelial growth factors; and (c) augmentation of host defense to infection. Initial translational efforts have shown signs of promise, but the results have not yielded the anticipated outcomes. One potential reason is the relatively low survival of MSCs in inflammatory conditions as shown in several studies. Therefore, strategies to boost the survival of MSCs are needed to enhance their therapeutic effect. Protease-activated receptors (PARs) may represent one such possibility as they are G-protein coupled receptors expressed by MSCs and control several facets of cell behavior. This review summarizes some of the existing literature about PARs and MSCs and presents possible future areas of investigation in order to develop potential, PAR-modified MSCs with enhanced therapeutic efficiency.

Mesenchymal stem cells in cancer progression and anticancer therapeutic resistance

Increasing evidence indicates that the tumor microenvironment appears to play an increasingly important role in cancer progression and therapeutic resistance. Several types of cells within the tumor stroma had distinct impacts on cancer progression, either promoting or inhibiting cancer cell growth. Mesenchymal stem cells (MSCs) are a distinct type of cells that is linked to tumor development. MSCs are recognized for homing to tumor locations and promoting or inhibiting cancer cell proliferation, angiogenesis and metastasis. Moreover, emerging studies suggests that MSCs are also involved in therapeutic resistance. In this review, we analyzed the existing researches and elaborate on the functions of MSCs in cancer progression and anticancer therapeutic resistance, demonstrating that MSCs may be a viable cancer therapeutic target.

Cell-Based Transplantation versus Cell Homing Approaches for Pulp-Dentin Complex Regeneration

Regenerative dentistry has paved the way for a new era for the replacement of damaged dental tissues. Whether the causative factor is dental caries, trauma, or chemical insult, the loss of the pulp vitality constitutes one of the major health problems worldwide. Two regenerative therapies were introduced for a fully functional pulp-dentin complex regeneration, namely, cell-based (cell transplantation) and cell homing (through revascularization or homing by injection of stem cells in situ or intravenously) therapies, with each demonstrating advantages as well as drawbacks, especially in clinical application. The present review is aimed at elaborating on these two techniques in the treatment of irreversibly inflamed or necrotic pulp, which is aimed at regenerating a fully functional pulp-dentin complex.

Understanding the Basis of Occurrence, Biosynthesis, and Implications of Thermostable Alkaline Proteases

The group of hydrolytic enzymes synonymously known as proteases is predominantly most favored for the class of industrial enzymes. The present work focuses on the thermostable nature of these proteolytic enzymes that occur naturally among mesophilic and thermophilic microbes. The broad thermo-active feature (40-80 °C), ease of cultivation, maintenance, and bulk production are the key features associated with these enzymes. Detailing of contemporary production technologies, and controllable operational parameters including the purification strategies, are the key features that justify their industrial dominance as biocatalysts. In addition, the rigorous research inputs by protein engineering and enzyme immobilization studies add up to the thermo-catalytic features and application capabilities of these enzymes. The work summarizes key features of microbial proteases that make them numero-uno for laundry, biomaterials, waste management, food and feed, tannery, and medical as well as pharmaceutical industries. The quest for novel and/or designed and engineered thermostable protease from unexplored sources is highly stimulating and will address the ever-increasing industrial demands.

Mesenchymal stem cells in cancer therapy; the art of harnessing a foe to a friend

For a long time, mesenchymal stem cells (MSCs) were discussed only as stem cells which could give rise to different types of cells. However, when it became clear that their presence in the tumor microenvironment (TME) was like a green light for tumorigenesis, they emerged from the ashes. This review was arranged to provide a comprehensive and precise description of MSCs' role in regulating tumorigenesis and to discuss the dark and the bright sides of cancer treatment strategies using MSCs. To gather the details about MSCs, we made an intensive literature review using keywords, including MSCs, tumor microenvironment, tumorigenesis, and targeted therapy. Through transferring cytokines, growth factors, and microRNAs, MSCs maintain the cancer stem cell population, increase angiogenesis, provide a facility for cancer metastasis, and shut down the anti-tumor activity of the immune system. Although MSCs progress tumorigenesis, there is a consensus that these cells could be used as a vehicle to transfer anti-cancer agents into the tumor milieu. This feature opened a new chapter in MSCs biology, this time from the therapeutic perspective. Although the data are not sufficient, the advent of new genetic engineering methods might make it possible to engage these cells as Trojan horses to eliminate the malignant population. So many years of investigation showed that MSCs are an important group of cells, residing in the TME, studying the function of which not only could add a delicate series of information to the process of tumorigenesis but also could revolutionize cancer treatment strategies.

Pivotal Role of Corneal Fibroblasts in Progression to Corneal Ulcer in Bacterial Keratitis

The shape and transparency of the cornea are essential for clear vision. However, its location at the ocular surface renders the cornea vulnerable to pathogenic microorganisms in the external environment. Pseudomonas aeruginosa and Staphylococcus aureus are two such microorganisms and are responsible for most cases of bacterial keratitis. The development of antimicrobial agents has allowed the successful treatment of bacterial keratitis if the infection is diagnosed promptly. However, no effective medical treatment is available after progression to corneal ulcer, which is characterized by excessive degradation of collagen in the corneal stroma and can lead to corneal perforation and corneal blindness. This collagen degradation is mediated by both infecting bacteria and corneal fibroblasts themselves, with a urokinase-type plasminogen activator (uPA)-plasmin-matrix metalloproteinase (MMP) cascade playing a central role in collagen destruction by the host cells. Bacterial factors stimulate the production by corneal fibroblasts of both uPA and pro-MMPs, released uPA mediates the conversion of plasminogen in the extracellular environment to plasmin, and plasmin mediates the conversion of secreted pro-MMPs to the active form of these enzymes, which then degrade stromal collagen. Bacterial factors also stimulate expression by corneal fibroblasts of the chemokine interleukin-8 and the adhesion molecule ICAM-1, both of which contribute to recruitment and activation of polymorphonuclear neutrophils, and these cells then further stimulate corneal fibroblasts via the secretion of interleukin-1. At this stage of the disease, bacteria are no longer necessary for collagen degradation. In this review, we discuss the pivotal role of corneal fibroblasts in corneal ulcer associated with infection by P. aeruginosa or S. aureus as well as the development of potential new modes of treatment for this condition.

Interleukin-1β-induced matrix metalloproteinase-3 via ERK1/2 pathway to promote mesenchymal stem cell migration

Human umbilical cord Wharton’s jelly derived mesenchymal stem cells (hUCMSCs), a source of cell therapy, have received a great deal of attention due to their homing or migrating ability in response to signals emanating from damaged sites. It has been found that IL-1β possesses the ability to induce the expression of matrix metalloproteinase-3 (MMP-3) in bone marrow MSCs. MMP-3 is involved in cell migration in various types of cells, including glioblastoma, vascular smooth muscle, and adult neural progenitor cells. In this study, we proposed that IL-1β influences hUCMSCs migration involving MMP-3. The expression level of MMP-3 in IL-1β-induced hUCMSCs was verified using cDNA microarray analysis, quantitative real-time PCR, ELISA and Western blot. Wound-healing and trans-well assay were used to investigate the cell migration and invasion ability of IL-1β-treated hUCMSCs. In addition, we pre-treated hUCMSCs with interleukin-1 receptor antagonist, MMP-3 inhibitors (ALX-260-165, UK 356618), or transfected with MMP-3 siRNA to confirm the role of MMP3 in IL-1β-induced cell migration. Our results showed that IL-1β induced MMP-3 expression is related to the migration of hUCMSCs. Moreover, extracellular signal-regulated protein kinases 1 and 2 (ERK1/2) inhibitor U0126, p38 inhibitor SB205380, JNK inhibitor SP600125 and Akt inhibitor GSK 690693 decreased IL-1β-induced MMP-3 mRNA and protein expression. The migration and invasion ability analyses showed that these inhibitors attenuated the IL-1β-induced migration and invasion ability of hUCMSCs. In conclusion, we have found that IL-1β induces the expression of MMP-3 through ERK1/2, JNK, p38 MAPK and Akt signaling pathways to enhance the migration of hUCMSCs. These results provide further understanding of the mechanisms in IL-1β-induced hUCMSCs migration to injury sites.

The Vital Roles of Mesenchymal Stem Cells and the Derived Extracellular Vesicles in Promoting Angiogenesis After Acute Myocardial Infarction

Acute myocardial infarction (AMI) is an event of ischemic myocardial necrosis caused by acute coronary artery occlusion, which ultimately leads to a large loss of cardiomyocytes. The prerequisite of salvaging ischemic myocardium and improving cardiac function of patients is to provide adequate blood perfusion in the infarcted area. Apart from reperfusion therapy, it is also urgent and imperative to promote angiogenesis. Recently, growing evidence based on promising preclinical data indicates that mesenchymal stem cells (MSCs) can provide therapeutic effects on AMI by promoting angiogenesis. Extracellular vesicles (EVs), membrane-encapsulated vesicles with complex cargoes, including proteins, nucleic acids, and lipids, can be derived from MSCs and represent part of their functions, so EVs also possess the ability to promote angiogenesis. However, poor control of the survival and localization of MSCs hindered clinical transformation and made scientists start looking for new approaches based on MSCs. Identifying the role of MSCs and their derived EVs in promoting angiogenesis can provide a theoretical basis for improved MSC-based methods, and ultimately promote the clinical treatment of AMI. This review highlights potential proangiogenic mechanisms of transplanted MSCs and the derived EVs after AMI and summarizes the latest literature concerning the novel methods based on MSCs to maximize the angiogenesis capability.

Mesenchymal Stem Cells as a Cornerstone in a Galaxy of Intercellular Signals: Basis for a New Era of Medicine

Around 40% of the population will suffer at some point in their life a disease involving tissue loss or an inflammatory or autoimmune process that cannot be satisfactorily controlled with current therapies. An alternative for these processes is represented by stem cells and, especially, mesenchymal stem cells (MSC). Numerous preclinical studies have shown MSC to have therapeutic effects in different clinical conditions, probably due to their mesodermal origin. Thereby, MSC appear to play a central role in the control of a galaxy of intercellular signals of anti-inflammatory, regenerative, angiogenic, anti-fibrotic, anti-oxidative stress effects of anti-apoptotic, anti-tumor, or anti-microbial type. This concept forces us to return to the origin of natural physiological processes as a starting point to understand the evolution of MSC therapy in the field of regenerative medicine. These biological effects, demonstrated in countless preclinical studies, justify their first clinical applications, and draw a horizon of new therapeutic strategies. However, several limitations of MSC as cell therapy are recognized, such as safety issues, handling difficulties for therapeutic purposes, and high economic cost. For these reasons, there is an ongoing tendency to consider the use of MSC-derived secretome products as a therapeutic tool, since they reproduce the effects of their parent cells. However, it will be necessary to resolve key aspects, such as the choice of the ideal type of MSC according to their origin for each therapeutic indication and the implementation of new standardized production strategies. Therefore, stem cell science based on an intelligently designed production of MSC and or their derivative products will be able to advance towards an innovative and more personalized medical biotechnology.

TL1A/TNFR2 Axis Enhances Immunoregulatory Effects of Bone Marrow Derived Mesenchymal Stem Cell by Indian Hedgehog Signaling Pathway

Background and Objectives

The immunomodulatory potential of mesenchymal stem cells (MSCs) can be regulated by a variety of molecules, especially cytokines. The inflammatory cytokine, TNF-like ligand 1A (TL1A), has been reported as an inflammation stimulator in-multiple autoimmune diseases. Here, we studied the effects of TL1A/TNF-receptor 2 (TNFR2) pathway on the therapeutic potency of bone marrow-derived MSCs (BMSCs).

Methods and Results

BMSCs, fibroblast-like synoviocytes (FLSs), and H9 and jurkat human T lymphocytes were used in this study. BMSCs paracrine activities, differentiation, proliferation, and migration were investigated after stimulation with TL1A, and intervened with anti-TNFR2. Additionally, the effects of TL1A on BMSCs therapeutic potency were evaluated by treating RA-FLSs, and H9 and jurkat T cells with TL1A-stimulated BMSCs conditioned medium (CM). Indian hedgehog (IHH) involvement was determined by gene silencing and treatment by recombinant IHH (rIHH). TL1A induced BMSCs stemness-related genes, COX-2, IL-6, IDO, TGF-β and HGF through TNFR2. Also, TL1A corrected biased differentiation and increased proliferation, and migration through TNFR2. Meanwhile, CM of TL1A-stimulated BMSCs decreased the inflammatory markers of RA-FLSs and T cells. Moreover, TL1A-stimulated BMSCs experienced IHH up-regulation coupled with NF-κB and STAT3 signaling up-regulation, while p53 and oxidative stress were down-regulated. Furthermore, treatment of BMSCs by rIHH increased their anti-inflammatory effects. More importantly, knockdown of IHH decreased the ability of TL1A-stimulated BMSCs to alleviating the inflammation in RA-FLSs and T cells.

Conclusions

This study reports the effects of TL1A/TNFR2 pathway on the biological behaviors and therapeutic potency of BMSCs through IHH. These findings could introduce novel procedures to increase the stemness of MSCs in cellular therapy.

Mesenchymal Stem Cell Immunomodulation: Mechanisms and Therapeutic Potential

Mesenchymal stem/stromal cells (MSCs) are multipotent cells that are emerging as the most promising means of allogeneic cell therapy. MSCs have inherent immunomodulatory characteristics, trophic activity, high invitro self-renewal ability, and can be readily engineered to enhance their immunomodulatory functions. MSCs affect the functions of most immune effector cells via direct contact with immune cells and local microenvironmental factors. Previous studies have confirmed that the immunomodulatory effects of MSCs are mainly communicated via MSC-secreted cytokines; however, apoptotic and metabolically inactivated MSCs have more recently been shown to possess immunomodulatory potential, in which regulatory T cells and monocytes play a key role. We review the immunomodulatory aspects of naïve and engineered MSCs, and discuss strategies for increasing the potential of successfully using MSCs in clinical settings.

Stem cell homing: From physiology to therapeutics

Stem cell homing is a multistep endogenous physiologic process that is also used by exogenously administered hematopoietic stem and progenitor cells (HSPCs). This multistep process involves cell migration and is essential for hematopoietic stem cell transplantation. The process can be manipulated to enhance ultimate engraftment potential, and understanding stem cell homing is also important to the understanding of stem cell mobilization. Homing is also of potential importance in the recruitment of marrow mesenchymal stem and stromal cells (MSCs) to sites of injury and regeneration. This process is less understood but assumes importance when these cells are used for repair purposes. In this review, the process of HSPC and MSC homing is examined, as are methods to enhance this process.

IL-1β enhances human placenta-derived mesenchymal stromal cells ability to mediate Th1/Th2 and Th1/CD4+IL-10+ T cell balance and regulates its adhesion, proliferation and migration via PD-L1

Human placenta-derived mesenchymal stromal cells (hPMSCs) are promising candidates for the treatment of graft-versus-host disease (GVHD), which is associated with high IL-1β levels. In this study, the effects of IL-1β and hPMSCs on each other were investigated by analyzing the proportion of Th1, Th2 and CD4⁺IL-10⁺ T cells and PD-L1 expression, as well as the adhesion, migration, and proliferation of hPMSCs. The results showed that hPMSCs decreased IL-1β levels and downregulated Th1/Th2 and Th1/CD4⁺IL-10⁺ T cells ratios in the GVHD model. The in vitro results revealed that IL-1β strengthened the hPMSCs capacity to reduce the Th1/Th2 and Th1/CD4⁺IL-10⁺ T cell ratios, inhibited the adhesion and proliferation of hPMSCs and increased PD-L1 expression on hPMSCs via the JAK and NF-κB pathways. Overall, these findings suggested that hPMSCs alleviate GVHD by decreasing IL-1β level and maintaining the balance among different T cell subsets. IL-1β enhanced the ability of hPMSCs to balance different T cell subsets and inhibited hPMSCs adhesion and proliferation by regulating PD-L1 expression via the JAK and NF-κB pathways.

Interleukin-1β Enhances Umbilical Cord Mesenchymal Stem Cell Adhesion Ability on Human Umbilical Vein Endothelial Cells via LFA-1/ICAM-1 Interaction

The migration of administered mesenchymal stem cells (MSCs) to sites of injury via the bloodstream has been demonstrated. However, the underlying mechanisms of umbilical cord MSC adhesion to endothelial cells during transendothelial migration are still unclear. In this study, our data showed that IL-1β induced LFA-1 expression on MSCs and ICAM-1 expression on HUVECs. We then pretreated MSCs with protein synthesis inhibitor cycloheximide. The results showed that IL-1β induced LFA-1 expression on the surface of MSCs via the protein synthesis pathway. Through the p38 MAPK signaling pathway inhibitor SB 203580, we found that IL-1β induces the expression of LFA-1 through p38 MAPK signaling and enhances ICAM-1 expression in HUVECs. In addition, IL-1β-induced MSC adhesion to HUVECs was found to be inhibited by IL-1RA and the LFA-1 inhibitor lovastatin. These results indicate that IL-1β promotes the cell adhesion of MSCs to HUVECs through LFA-1/ICAM-1 interaction. We address the evidence that the cell adhesion mechanism of IL-1β promotes MSC adhesion to HUVECs. The implications of these findings could enhance the therapeutic potential of MSCs.

Increased in vitro migration of human umbilical cord mesenchymal stem cells toward acellular foreskin treated with bacterial derivatives of monophosphoryl lipid A or supernatant of Lactobacillus acidophilus

Migration and homing are known as critical steps toward regeneration of damaged tissues via cell therapies. Among various cellular sources of stem cells, the umbilical cord has been thus recognized as an interesting one endowed with high benefits. Accordingly, the main objective of the present study was to determine whether monophosphoryl lipid A (MPLA) or supernatant of Lactobacillus acidophilus (SLA) could increase migration of human umbilical cord mesenchymal stem cells (hUMSCs) toward acellular foreskin or not. In this study, the hUMSCs were isolated and cultured through acellular MPLA- or SLA-treated foreskin. Expression of some migration genes (i.e., VCAM-1, MMP-2, VLA-4, CXCR-4, and VEGF) was also investigated using quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR). Moreover; vimentin, cytokeratin 5 (CK5), and matrix metalloproteinases-2 (MMP-2) were detected via immunohistochemistry (IHC) analysis. The hUMSCs in the presence of MPLA- or SLA-treated foreskin showed more tissue tropism compared with those in the control group. Besides, the scanning electron microscopy (SEM) results established that the hUMSCs had more migratory activity in the presence of MPLA- or SLA-treated foreskin than the untreated one. The IHC analysis results correspondingly indicated that expression of vimentin, CK5, and MMP-2 proteins had augmented in both treatments compared with those in the control group. It was concluded that MPLA had revealed more prominent results than SLA, even though both treatments could be regarded as inducing factors in migration. Ultimately, it was suggested to introduce the use of MPLA and probiotic components as a promising approach to improve therapies in regenerative medicine.

Does co-transplantation of mesenchymal and spermatogonial stem cells improve reproductive efficiency and safety in mice?

Background

Spermatogonial stem cell transplantation (SSCT) is a promising therapy in restoring the fertility of childhood cancer survivors. However, the low efficiency of SSCT is a significant concern. SSCT could be improved by co-transplanting transforming growth factor beta 1 (TGFβ1)-induced mesenchymal stem cells (MSCs). In this study, we investigated the reproductive efficiency and safety of co-transplanting spermatogonial stem cells (SSCs) and TGFβ1-induced MSCs.

Methods

A mouse model for long-term infertility was used to transplant SSCs (SSCT, n = 10) and a combination of SSCs and TGFβ1-treated MSCs (MSi-SSCT, n = 10). Both transplanted groups and a fertile control group (n = 7) were allowed to mate naturally to check the reproductive efficiency after transplantation. Furthermore, the testes from transplanted males and donor-derived male offspring were analyzed for the epigenetic markers DNA methyltransferase 3A (DNMT3A) and histone 4 lysine 5 acetylation (H4K5ac).

Results

The overall tubular fertility index (TFI) after SSCT (76 ± 12) was similar to that after MSi-SSCT (73 ± 14). However, the donor-derived TFI after MSi-SSCT (26 ± 14) was higher compared to the one after SSCT (9 ± 5; P = 0.002), even after injecting half of the number of SSCs in MSi-SSCT. The litter sizes after SSCT (3.7 ± 3.7) and MSi-SSCT (3.7 ± 3.6) were similar but differed significantly with the control group (7.6 ± 1.0; P < 0.001). The number of GFP⁺ offspring per litter obtained after SSCT (1.6 ± 0.5) and MSi-SSCT (2.0 ± 1.0) was also similar. The expression of DNMT3A and H4K5ac in germ cells of transplanted males was found to be significantly reduced compared to the control group. However, in donor-derived offspring, DNMT3A and H4K5ac followed the normal pattern.

Conclusion

Co-transplanting SSCs and TGFβ1-treated MSCs results in reproductive efficiency as good as SSCT, even after transplanting half the number of SSCs. Although transplanted males showed lower expression of DNMT3A and H4K5ac in donor-derived germ cells, the expression was restored to normal levels in germ cells of donor-derived offspring. This procedure could become an efficient method to restore fertility in a clinical setup, but more studies are needed to ensure safety in the long term.

AFM-based Analysis of Wharton's Jelly Mesenchymal Stem Cells

Wharton's jelly mesenchymal stem cells (WJ-MSCs) are multipotent stem cells that can be used in regenerative medicine. However, to reach the high therapeutic efficacy of WJ-MSCs, it is necessary to obtain a large amount of MSCs, which requires their extensive in vitro culturing. Numerous studies have shown that in vitro expansion of MSCs can lead to changes in cell behavior; cells lose their ability to proliferate, differentiate and migrate. One of the important measures of cells' migration potential is their elasticity, determined by atomic force microscopy (AFM) and quantified by Young's modulus. This work describes the elasticity of WJ-MSCs during in vitro cultivation. To identify the properties that enable transmigration, the deformability of WJ-MSCs that were able to migrate across the endothelial monolayer or Matrigel was analyzed by AFM. We showed that WJ-MSCs displayed differences in deformability during in vitro cultivation. This phenomenon seems to be strongly correlated with the organization of F-actin and reflects the changes characteristic for stem cell maturation. Furthermore, the results confirm the relationship between the deformability of WJ-MSCs and their migration potential and suggest the use of Young's modulus as one of the measures of competency of MSCs with respect to their possible use in therapy.

The multifaceted role of mesenchymal stem cells in cancer

Mesenchymal stem cells (MSCs) are multipotent stem cells derived from the mesoderm that give rise to several mesenchymal lineages, including osteoblasts, adipocytes, chondrocytes and myocytes. Their potent ability to home to tumors coupled with their differentiation potential and immunosuppressive function positions MSCs as key regulators of tumor fate. Here we review the existing knowledge on the involvement of MSCs in multiple tumor-promoting processes, including angiogenesis, epithelial-mesenchymal transition, metastasis, immunosuppression and therapy resistance. We also discuss the clinical potential of MSC-based therapy for cancer.

Co-transplantation of mesenchymal stem cells improves spermatogonial stem cell transplantation efficiency in mice

Background

Spermatogonial stem cell transplantation (SSCT) could become a fertility restoration tool for childhood cancer survivors. However, since in mice, the colonization efficiency of transplanted spermatogonial stem cells (SSCs) is only 12%, the efficiency of the procedure needs to be improved before clinical implementation is possible. Co-transplantation of mesenchymal stem cells (MSCs) might increase colonization efficiency of SSCs by restoring the SSC niche after gonadotoxic treatment.

Methods

A mouse model for long-term infertility was developed and used to transplant SSCs (SSCT, n = 10), MSCs (MSCT, n = 10), a combination of SSCs and MSCs (MS-SSCT, n = 10), or a combination of SSCs and TGFß1-treated MSCs (MSi-SSCT, n = 10).

Results

The best model for transplantation was obtained after intraperitoneal injection of busulfan (40 mg/kg body weight) at 4 weeks followed by CdCl₂ (2 mg/kg body weight) at 8 weeks of age and transplantation at 11 weeks of age. Three months after transplantation, spermatogenesis resumed with a significantly better tubular fertility index (TFI) in all transplanted groups compared to non-transplanted controls (P < 0.001). TFI after MSi-SSCT (83.3 ± 19.5%) was significantly higher compared to MS-SSCT (71.5 ± 21.7%, P = 0.036) but did not differ statistically compared to SSCT (78.2 ± 12.5%). In contrast, TFI after MSCT (50.2 ± 22.5%) was significantly lower compared to SSCT (P < 0.001). Interestingly, donor-derived TFI was found to be significantly improved after MSi-SSCT (18.8 ± 8.0%) compared to SSCT (1.9 ± 1.1%; P < 0.001), MSCT (0.0 ± 0.0%; P < 0.001), and MS-SSCT (3.4 ± 1.9%; P < 0.001). While analyses showed that both native and TGFß1-treated MSCs maintained characteristics of MSCs, the latter showed less migratory characteristics and was not detected in other organs.

Conclusion

Co-transplanting SSCs and TGFß1-treated MSCs significantly improves the recovery of endogenous SSCs and increases the homing efficiency of transplanted SSCs. This procedure could become an efficient method to treat infertility in a clinical setup, once the safety of the technique has been proven.

Electronic supplementary material

The online version of this article (10.1186/s13287-018-1065-0) contains supplementary material, which is available to authorized users.