Therapeutic Applications of Mesenchymal Stem Cells for Systemic Lupus Erythematosus

Mesenchymal stem cell transplantation may be able to induce immunological tolerance in systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is a common, potentially fatal autoimmune disease involving a significant inflammatory response. SLE is characterised by failure of self-tolerance and activation of autoreactive lymphocytes, leading to persistent disease. Although current treatments achieve some improvement in patients, some SLE patients are refractory and others relapse after drug withdrawal. The toxicity of current drug regimens, with recurrent infections, together with ongoing inflammation, contribute significantly to the progressive decline in organ function. Therefore, the clinical management of SLE requires more effective and less toxic treatments, ideally inducing complete remission and self-tolerance. In this context, recently developed cell therapies based on mesenchymal stem cells (MSCs) represent a promising and safe strategy in SLE. MSCs inhibit the activation of B cells, prevent the differentiation of CD4⁺ T cells into autoreactive T cells, reprogram macrophages with anti-inflammatory effects and inhibit dendritic cells (DCs), limiting their activity as antigen-presenting cells. In addition, MSCs could induce antigen-specific tolerance by enhancing anergy processes in autoreactive cells - by inhibiting the maturation of antigen-presenting DCs, blocking the T cell receptor (TcR) pathway and secreting inhibitory molecules -, increasing apoptotic activity to eliminate them, and activating regulatory T cells (Tregs) to enhance their proliferation and induction of tolerogenic DCs. Thus, induction of self-tolerance leads to immune balance, keeping inflammation under control and reducing lupus flares.

Dysregulated balance in Th17/Treg axis of Pristane-induced lupus mouse model, are mesenchymal stem cells therapeutic?

BACKGROUND

Despite advances in general and targeted immunosuppressive therapies, limiting all mainstay treatment options in refractory systemic lupus erythematosus (SLE) cases has necessitated the development of new therapeutic strategies. Mesenchymal stem cells (MSCs) have recently emerged with unique properties, including a solid propensity to reduce inflammation, exert immunomodulatory effects, and repair injured tissues.

METHODS

An animal model of acquired SLE mice was induced via intraperitoneal immunization with Pristane and affirmed by measuring specific biomarkers. Bone marrow (BM) MSCs were isolated from healthy BALB/c mice and cultured in vitro, then were identified and confirmed by flow cytometry and cytodifferentiation. Systemic MSCs transplantation was performed and then several parameters were analyzed and compared, including specific cytokines (IL-17, IL-4, IFN-ɣ, TGF-β) at the serum level, the percentage of Th cell subsets (Treg/Th17, Th1/Th2) in splenocytes, and also the relief of lupus nephritis, respectively by enzyme-linked immunosorbent assay (ELISA), flow cytometry analysis and by hematoxylin & eosin staining and also immunofluorescence assessment. Experiments were carried out with different initiation treatment time points (early and late stages of disease). Analysis of variance (ANOVA) followed by post hoc Tukey's test was used for multiple comparisons.

RESULTS

The rate of proteinuria, anti-double-stranded deoxyribonucleic acid (anti-dsDNA) antibodies, and serum creatinine levels decreased with BM-MSCs transplantation. These results were associated with attenuated lupus renal pathology in terms of reducing IgG and C3 deposition and lymphocyte infiltration. Our findings suggested that TGF-β (associated with lupus microenvironment) can contribute to MSC-based immunotherapy by modulating the population of TCD4⁺ cell subsets. Obtained results indicated that MSCs-based cytotherapy could negatively affect the progression of induced SLE by recovering the function of Treg cells, suppressing Th1, Th2, and Th17 lymphocyte function, and downregulating their pro-inflammatory cytokines.

CONCLUSION

MSC-based immunotherapy showed a delayed effect on the progression of acquired SLE in a lupus microenvironment-dependent manner. Allogenic MSCs transplantation revealed the ability to re-establish the balance of Th17/Treg, Th1/Th2 and restore the plasma cytokines network in a pattern dependent on disease conditions. The conflicting results of early versus advanced therapy suggest that MSCs may produce different effects depending on when they are administered and their activation status.

Modulation of Mesenchymal Stem Cells-Mediated Adaptive Immune Effectors' Repertoire in the Recovery of Systemic Lupus Erythematosus

The breakdown of self-tolerance of the immune response can lead to autoimmune conditions in which chronic inflammation induces tissue damage. Systemic lupus erythematosus (SLE) is a debilitating multisystemic autoimmune disorder with a high prevalence in women of childbearing age; however, SLE incidence, prevalence, and severity are strongly influenced by ethnicity. Although the mystery of autoimmune diseases remains unsolved, disturbance in the proportion and function of B cell subsets has a major role in SLE's pathogenesis. Additionally, colocalizing hyperactive T helper cell subgroups within inflammatory niches are indispensable. Despite significant advances in standard treatments, nonspecific immunosuppression, the risk of serious infections, and resistance to conventional therapies in some cases have raised the urgent need for new treatment strategies. Without the need to suppress the immune system, mesenchymal stem cells (MSCs), as ''smart" immune modulators, are able to control cellular and humoral auto-aggression responses by participating in precursor cell development. In lupus, due to autologous MSCs disorder, the ability of allogenic engrafted MSCs in tissue regeneration and resetting immune homeostasis with the provision of a new immunocyte repertoire has been considered simultaneously. In Brief The bone marrow mesenchymal stem cells (BM-MSCs) lineage plays a critical role in maintaining the hematopoietic stem-cell microstructure and modulating immunocytes. The impairment of BM-MSCs and their niche partially contribute to the pathogenesis of SLE-like diseases. Allogenic MSC transplantation can reconstruct BM microstructure, possibly contributing to the recovery of immunocyte phenotype restoration of immune homeostasis. In terms of future prospects of MSCs, artificially gained by ex vivo isolation and culture adaptation, the wide variety of potential mediators and mechanisms might be linked to the promotion of the immunomodulatory function of MSCs.

TNFAIP6 defines the MSC subpopulation with enhanced immune suppression activities

Background

Mesenchymal stromal/stem cells (MSCs) have been intensively investigated in both pre-clinical and clinical studies. However, the therapeutic efficacy varies resulting from the heterogenicity of MSCs. Therefore, purifying the specific MSC subpopulation with specialized function is necessary for their therapeutic applications.

Methods

The large-scale RNA sequencing analysis was performed to identify potential cell markers for the mouse MSCs. Then, the immune suppression activities of the purified MSC subpopulation were assessed in vitro and in vivo.

Results

The TNFAIP6 (tumor necrosis factor alpha-induced protein 6) has been identified as a potential cell marker for mouse MSCs, irrespective of tissue origin and laboratory origin. The TNFAIP6⁺ mouse MSCs showed enhanced immune suppression activities and improved therapeutic effects on the mouse model of acute inflammation, resulting from faster response to immune stimulation.

Conclusions

Therefore, we have demonstrated that the TNFAIP6⁺ MSC subpopulation has enhanced immune suppression capabilities.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13287-022-03176-5.

The Therapeutic Potential of Mesenchymal Stromal Cells for Regenerative Medicine: Current Knowledge and Future Understandings

In recent decades, research on the therapeutic potential of progenitor cells has advanced considerably. Among progenitor cells, mesenchymal stromal cells (MSCs) have attracted significant interest and have proven to be a promising tool for regenerative medicine. MSCs are isolated from various anatomical sites, including bone marrow, adipose tissue, and umbilical cord. Advances in separation, culture, and expansion techniques for MSCs have enabled their large-scale therapeutic application. This progress accompanied by the rapid improvement of transplantation practices has enhanced the utilization of MSCs in regenerative medicine. During tissue healing, MSCs may exhibit several therapeutic functions to support the repair and regeneration of injured tissue. The process underlying these effects likely involves the migration and homing of MSCs, as well as their immunotropic functions. The direct differentiation of MSCs as a cell replacement therapeutic mechanism is discussed. The fate and behavior of MSCs are further regulated by their microenvironment, which may consequently influence their repair potential. A paracrine pathway based on the release of different messengers, including regulatory factors, chemokines, cytokines, growth factors, and nucleic acids that can be secreted or packaged into extracellular vesicles, is also implicated in the therapeutic properties of MSCs. In this review, we will discuss relevant outcomes regarding the properties and roles of MSCs during tissue repair and regeneration. We will critically examine the influence of the local microenvironment, especially immunological and inflammatory signals, as well as the mechanisms underlying these therapeutic effects. Importantly, we will describe the interactions of local progenitor and immune cells with MSCs and their modulation during tissue injury. We will also highlight the crucial role of paracrine pathways, including the role of extracellular vesicles, in this healing process. Moreover, we will discuss the therapeutic potential of MSCs and MSC-derived extracellular vesicles in the treatment of COVID-19 (coronavirus disease 2019) patients. Overall, this review will provide a better understanding of MSC-based therapies as a novel immunoregenerative strategy.

Stem cell therapy in dermatology

Stem cells are precursor cells present in many tissues with ability to differentiate into various types of cells. This interesting property of plasticity can have therapeutic implications and there has been substantial research in this field in last few decades. As a result, stem cell therapy is now used as a therapeutic modality in many conditions, and has made its way in dermatology too. Stem cells can be classified on the basis of their source and differentiating capacity. In skin, they are present in the inter-follicular epidermis, hair follicle, dermis and adipose tissue, which help in maintaining normal skin homeostasis and repair and regeneration during injury. In view of their unique properties, they have been employed in treatment of several dermatoses including systemic sclerosis, systemic lupus erythematosus, scleromyxedema, alopecia, Merkel cell carcinoma, pemphigus vulgaris, psoriasis, wound healing, epidermolysis bullosa and even aesthetic medicine, with variable success. The advent of stem cell therapy has undoubtedly brought us closer to curative treatment of disorders previously considered untreatable. Nevertheless, there are multiple lacunae which need to be addressed including ideal patient selection, timing of intervention, appropriate conditioning regimens, post-intervention care and cost effectiveness. Further research in these aspects would help optimize the results of stem cell therapy.

Enhanced renoprotective effect of GDNF-modified adipose-derived mesenchymal stem cells on renal interstitial fibrosis

Background

The therapeutic effect of mesenchymal stem cells (MSCs) from human adipose tissue on renal interstitial fibrosis has been demonstrated by several groups. However, the way to enhance the renoprotective effect of adipose-derived mesenchymal stem cells (AMSCs) and the possible mechanisms are still unclear. The present study aimed to determine whether glial cell line-derived neurotrophic factor (GDNF)-modified AMSCs hold an enhanced protective effect on renal fibrosis.

Methods

AMSCs were isolated and purified for culture. The gene GDNF has been constructed to transfect into AMSCs. The ability of GFP-AMSCs and GDNF-AMSCs supernatants to promote tube formation of endothelial cells, repair damaged endothelial cell junctions, and improve endothelial cell function was compared by using tube formation assay, immunofluorescence techniques, and vascular ring assay, respectively. Furthermore, HE and Masson staining were used to observe the histological morphology of the kidney in vivo. Peritubular capillary changes were detected and analyzed by fluorescence microangiography (FMA). Meanwhile, the hypoxia, oxidative stress, fibrotic markers, and PI3K/Akt pathway proteins were measured by western blot or qRT-PCR technics.

Results

Compared with GFP-AMSCs only, GDNF-AMSCs could enhance the repair of injured endothelial cells and promote angiogenesis through secreting more growth factors in the supernatant of GDNF-AMSC culture media demonstrated in vitro studies. Studies in vivo, unilateral ureteral obstruction (UUO)-induced mice were injected with transfected AMSCs through their tail veins. We showed that enhanced homing of AMSCs was observed in the GDNF-AMSC group compared with the GFP-AMSC group. The animals treated with GDNF-AMSCs exhibited an improvement of capillary rarefaction and fibrosis induced by obstructed kidney compared with the GFP-AMSC group. Furthermore, we reported that GDNF-AMSCs protect renal tissues against microvascular injuries via activation of the PI3K/Akt signaling pathway. Therefore, GDNF-AMSCs further ameliorated the tissue hypoxia, suppressed oxidative stress, and finally inhibited endothelial to mesenchymal transition noting by decreased coexpression of endothelial cell (CD31) and myofibroblast (a-SMA) markers.

Conclusion

Collectively, our data indicated that the GDNF gene enhances the ability of AMSCs in improving renal microcirculation through PI3K/Akt/eNOS signaling pathway and afterward inhibit the EndMT process and kidney fibrogenesis, which should have a vast of implications in designing future remedies for chronic kidney disease (CKD) treatment.

Phorbol ester activates human mesenchymal stem cells to inhibit B cells and ameliorate lupus symptoms in MRL.Fas lpr mice

Rationale: Systemic lupus erythematosus (SLE) is a multi-organ autoimmune disease characterized by autoantibody production by hyper-activated B cells. Although mesenchymal stem cells (MSCs) ameliorate lupus symptoms by inhibiting T cells, whether they inhibit B cells has been controversial. Here we address this issue and reveal how to prime MSCs to inhibit B cells and improve the efficacy of MSCs in SLE.

Methods: We examined the effect of MSCs on purified B cells in vitro and the therapeutic efficacy of MSCs in lupus-prone MRL.Fas^lpr mice. We screened chemicals for their ability to activate MSCs to inhibit B cells.

Results: Mouse bone marrow-derived MSCs inhibited mouse B cells in a CXCL12-dependent manner, whereas human bone marrow-derived MSCs (hMSCs) did not inhibit human B (hB) cells. We used a chemical approach to overcome this hurdle and found that phorbol myristate acetate (PMA), phorbol 12,13-dibutyrate, and ingenol-3-angelate rendered hMSCs capable of inhibiting IgM production by hB cells. As to the mechanism, PMA-primed hMSCs attracted hB cells in a CXCL10-dependent manner and induced hB cell apoptosis in a PD-L1-dependent manner. Finally, we showed that PMA-primed hMSCs were better than naïve hMSCs at ameliorating SLE progression in MRL.Fas^lpr mice.

Conclusion: Taken together, our data demonstrate that phorbol esters might be good tool compounds to activate MSCs to inhibit B cells and suggest that our chemical approach might allow for improvements in the therapeutic efficacy of hMSCs in SLE.

The Global Emergency of Novel Coronavirus (SARS-CoV-2): An Update of the Current Status and Forecasting

Over the past two decades, there have been two major outbreaks where the crossover of animal Betacoronaviruses to humans has resulted in severe acute respiratory syndrome coronavirus (SARS-CoV) and Middle East respiratory syndrome coronavirus (MERS-CoV). In December 2019, a global public health concern started with the emergence of a new strain of coronavirus (SARS-CoV-2 or 2019 novel coronavirus, 2019-nCoV) which has rapidly spread all over the world from its origin in Wuhan, China. SARS-CoV-2 belongs to the Betacoronavirus genus, which includes human SARS-CoV, MERS and two other human coronaviruses (HCoVs), HCoV-OC43 and HCoV-HKU1. The fatality rate of SARS-CoV-2 is lower than the two previous coronavirus epidemics, but it is faster spreading and the large number of infected people with severe viral pneumonia and respiratory illness, showed SARS-CoV-2 to be highly contagious. Based on the current published evidence, herein we summarize the origin, genetics, epidemiology, clinical manifestations, preventions, diagnosis and up to date treatments of SARS-CoV-2 infections in comparison with those caused by SARS-CoV and MERS-CoV. Moreover, the possible impact of weather conditions on the transmission of SARS-CoV-2 is also discussed. Therefore, the aim of the present review is to reconsider the two previous pandemics and provide a reference for future studies as well as therapeutic approaches.

MiR-153-3p induces immune dysregulation by inhibiting PELI1 expression in umbilical cord-derived mesenchymal stem cells in patients with systemic lupus erythematosus

Mesenchymal stem cells (MSCs) are identified as a promising tool for the treatment of autoimmune diseases, and several microRNAs (miRNAs) are shown to exhibit vital roles in immune diseases. However, their function and mechanism in systemic lupus erythematosus (SLE) is still unclear. The qRT-PCR analysis was employed to investigate level of miR-153-3p. Subsequently, western blot and luciferase reporter assays were carried out to determine miR-153-3p targets. Cell proliferation and migration were determined using EdU proliferation assays and transwell migration assays. Apoptosis levels were evaluated by annexin V staining and flow cytometry. We used human umbilical cord-derived mesenchymal stem cells (UC-MSCs) transplantation to treat MRL/lpr mice. It was observed that miR-153-3p was upregulated in patients with SLE, and was closely related to SLE disease activity. Overexpression of miR-153-3p decreased UC-MSCs proliferation and migration, and weakened UC-MSCs-mediated decrease of follicular T helper (Tfh) cells and increase of regulatory T (Treg) cells through repressing PELI1 in vitro. We also found that PELI1 overexpression abolished the function of miR-153-3p on UC-MSCs. Furthermore, miR-153-3p overexpression weakened the therapeutic effect of UC-MSCs in MRL/lpr mice in vivo. Taken together, all data suggested that miR-153-3p is a mediator of SLE UC-MSCs regulation and may function as a new therapeutic target for the treatment of lupus.

Cost-effective storage solution for delivering umbilical cord with efficient isolation of mesenchymal stem cells

Mesenchymal stem cells (MSCs) represent a promising therapeutic candidate for treating many diseases. However, their proliferation and therapeutic abilities decline during the aging process and disease development. Therefore, fetal MSCs derived from the umbilical cord (UC) attract more attention. Storing and delivering the UC is one critical step for efficient MSC isolation. Although the culture medium-based solution is suitable for UC storage, it is not feasible for large-scale preparation because of its high price. Thus, we demonstrate here that a simple solution containing a pH buffering reagent, calcium, magnesium and glucose could be used as a cost-effective storage solution for UC delivery and efficient MSC isolation.

Effect of Human Mesenchymal Stem Cells on Xenogeneic T and B Cells Isolated from Lupus-Prone MRL.Fas lpr Mice

Systemic lupus erythematosus (SLE) is an autoimmune disease, which is characterized by hyperactivation of T and B cells. Human mesenchymal stem cells (hMSCs) ameliorate the progression of SLE in preclinical studies using lupus-prone MRL.Fas^lpr mice. However, whether hMSCs inhibit the functions of xenogeneic mouse T and B cells is not clear. To address this issue, we examined the in vitro effects of hMSCs on T and B cells isolated from MRL.Fas^lpr mice. Naïve hMSCs inhibited the functions of T cells but not B cells. hMSCs preconditioned with IFN-γ (i) inhibited the proliferation of and IgM production by B cells, (ii) attracted B cells for cell–cell interactions in a CXCL10-dependent manner, and (iii) inhibited B cells by producing indoleamine 2,3-dioxygenase. In summary, our data demonstrate that hMSCs exert therapeutic activity in mice in three steps: first, naïve hMSCs inhibit the functions of T cells, hMSCs are then activated by IFN-γ, and finally, they inhibit B cells.

Additive Therapeutic Effects of Mesenchymal Stem Cells and IL-37 for Systemic Lupus Erythematosus

BACKGROUND

Although mesenchymal stem cells (MSCs) might offer a promising strategy for treating SLE, their immunoregulatory plasticity makes their therapeutic effects unpredictable. Whether overexpressing IL-37, an IL-1 family member with immunosuppressive activity, might enhance the therapeutic effects of these cells for SLE is unknown.

METHODS

We genetically modified MSCs to overexpress IL-37 and assessed their effects on immune suppression in vitro. We also evaluated the effects of such cells versus effects of various controls after transplanting them into MRL/lpr mice (model of SLE).

RESULTS

Stem cell characteristics did not appear altered in MSCs overexpressing IL-37. These cells had enhanced immunosuppression in vitro in terms of inhibiting splenocyte proliferation, reducing proinflammatory factors (IL-1β, TNF-α, IL-17, and IL-6), and suppressing autoantibodies (anti-dsDNA and anti-ANA). Compared with animals receiving control MSCs or IL-37 treatment alone, MRL/lpr mice transplanted with IL-37-overexpressing cells displayed improved survival and reduced signs of SLE (indicated by urine protein levels, spleen weight, and renal pathologic scores); they also had significantly lower expression of proinflammatory factors, lower total antibody levels in serum and urine, lower autoantibody production, and showed reduced T cell numbers in the serum and kidney. Expression of IL-37 by MSCs can maintain higher serum levels of IL-37, and MSCs had prolonged survival after transplantation, perhaps through IL-37 suppressing the inflammatory microenvironment.

CONCLUSIONS

Mutually reinforcing interaction between MSCs and IL-37 appears to underlie their additive therapeutic effects. Genetic modification to overexpress IL-37 might offer a way to enhance the stability and effectiveness of MSCs in treating SLE.

Mesenchymal stem cells: Cell therapy and regeneration potential

Rapid advances in the isolation of multipotent progenitor cells, routinely called mesenchymal stromal/stem cells (MSCs), from various human tissues and organs have provided impetus to the field of cell therapy and regenerative medicine. The most widely studied sources of MSCs include bone marrow, adipose, muscle, peripheral blood, umbilical cord, placenta, fetal tissue, and amniotic fluid. According to the standard definition of MSCs, these clonal cells adhere to plastic, express cluster of differentiation (CD) markers such as CD73, CD90, and CD105 markers, and can differentiate into adipogenic, chondrogenic, and osteogenic lineages in vitro. However, isolated MSCs have been reported to vary in their potency and self-renewal potential. As a result, the MSCs used for clinical applications often lead to variable or even conflicting results. The lack of uniform characterization methods both in vitro and in vivo also contributes to this confusion. Therefore, the name "MSCs" itself has been increasingly questioned lately. As the use of MSCs is expanding rapidly, there is an increasing need to understand the potential sources and specific potencies of MSCs. This review discusses and compares the characteristics of MSCs and suggests that the variations in their distinctive features are dependent on the source and method of isolation as well as epigenetic changes during maintenance and growth. We also discuss the potential opportunities and challenges of MSC research with the hope to stimulate their use for therapeutic and regenerative medicine.

Rapid identification of genome-edited mesenchymal stem cell colonies via Cas9

Mesenchymal stem cells (MSCs) have been intensively investigated and widely applied in regenerative medicine and immune modulation. However, their efficacy declines during the aging or disease process. Thus, genome-edited MSCs with over-expression or inhibition of specific genes hold a great deal of promise in terms of their therapeutic application. Here we optimized the direct PCR approach for rapid identification of genome-edited MSCs with only ten cells required, which reduces the time and labor to expand the MSC colonies. Combined with our previously optimized guide RNA structure and plasmid construction strategy for Cas9, we successfully identified MSC colonies over-expressing IL-10 in the AAVS1 locus.