MSC Injection Research Articles

Intraosseous Delivery of Mesenchymal Stem Cells for the Treatment of Bone and Hematological Diseases

Mesenchymal stem cells are used most in regenerative medicine due to their capacities in differentiation and immune modulation. The intraosseous injection of MSC into the bone has been recommended because of expected outcomes for retention, bioavailability, and enhanced therapeutic efficacy, particularly in conditions involving the bone, such as osteoporosis and osteonecrosis. A review of the intraosseous delivery of mesenchymal stem cells in comparison with intravenous and intra-arterial delivery methods will be subjected to critical examination. This delivery mode fares better regarding paracrine signaling and immunomodulation attributes, which are the cornerstone of tissue regeneration and inflammation reduction. The local complications and technical challenges still apply with this method. This study was more focused on further research soon to be conducted to further elucidate long-term safety and efficacy of intraosseous mesenchymal stem cell therapy. Though much has been achieved with very impressive progress in this field, it is worth noting that more studies need to be put into place so that this technique can be established as a routine approach, especially with further research in biomaterials, gene therapy, and personalized medicine.

Single intra-articular injection of human synovial membrane MSC from grade IV knee osteoarthritis patient improve cartilage repair in OA rat model

AimThis study aims to assess the effectiveness of therapy of human synovial membrane-derived MSCs (SM-MSC) from OA grade IV patients in treating knee OA.MethodsSM-MSC were isolated from patients undergoing total knee replacement surgery, cultured to the fourth passage, and characterized using flow cytometry. Differentiation potential was assessed through lineage-specific staining. Osteoarthritis was induced in 24 Wistar rats via monosodium iodoacetate (MIA). The rats were divided into three groups: negative control, OA control, and OA treated with SM-MSC. Radiological, histopathological, and molecular analyses were conducted to evaluate cartilage repair and gene expression.ResultsFlow cytometry confirmed the MSC phenotype of SM-MSC, and successful differentiation was observed. Radiological and histopathological analyses showed significant improvement in the SM-MSC treated group, with reduced cartilage damage and higher Safranin O staining compared to the OA control group. Gene expression analysis indicated increased type-2 collagen (COL-2) expression in the SM-MSC treated group, although MMP-13 levels remained unchanged across all groups.ConclusionHuman SM-MSCs from OA grade IV patients significantly improved cartilage repair in an OA rat model, demonstrating their potential as a therapeutic option for OA. To enhance long-term efficacy and anti-inflammatory effects, further studies are needed to optimize treatment protocols, including injection frequency and dosage.

Chitosan-PNIPAM Thermogel Associated with Hydrogel Microspheres as a Smart Formulation for MSC Injection.

Regenerative medicine based on cell therapy has emerged as a promising approach for the treatment of various medical conditions. However, the success of cell therapy heavily relies on the development of suitable injectable hydrogels that can encapsulate cells and provide a conducive environment for their survival, proliferation, and tissue regeneration. Herein, we address the medical need for cyto- and biocompatible injectable hydrogels by reporting on the synthesis of a hydrogel-forming thermosensitive copolymer. The copolymer was synthesized by grafting poly(N-isopropylacrylamide-co-carboxymethyl acrylate) (PNIPAM-COOH) onto chitosan through amide coupling. This chemical modification resulted in the formation of hydrogels that exhibit a sol-gel transition with an onset at approximately 27 °C, making them ideal for use in injectable applications. The hydrogels supported the survival and proliferation of cells for several days, which is critical for cell encapsulation. Furthermore, the study evaluates the addition of collagen/chitosan hybrid microspheres to support the adhesion of mesenchymal stem cells within the hydrogels. Altogether, these results demonstrate the potential of the PNIPAM-chitosan thermogel for cell encapsulation and its possible applications in regenerative medicine.

Beneficial Effect of Sirolimus-Pretreated Mesenchymal Stem Cell Implantation on Diabetic Retinopathy in Rats.

Diabetic retinopathy (DR) is a vision-threatening complication that affects virtually all diabetic patients. Various treatments have been attempted, but they have many side effects and limitations. Alternatively, stem cell therapy is being actively researched, but it faces challenges due to a low cell survival rate. In this study, stem cells were pretreated with sirolimus, which is known to promote cell differentiation and enhance the survival rate. Additionally, the subconjunctival route was employed to reduce complications following intravitreal injections. Diabetes mellitus was induced by intraperitoneal injection of 55 mg/kg of streptozotocin (STZ), and DR was confirmed at 10 weeks after DM induction through electroretinogram (ERG). The rats were divided into four groups: intact control group (INT), diabetic retinopathy group (DR), DR group with subconjunctival MSC injection (DR-MSC), and DR group with subconjunctival sirolimus-pretreated MSC injection (DR-MSC-S). The effects of transplantation were evaluated using ERG and histological examinations. The ERG results showed that the DR-MSC-S group did not significantly differ from the INT in b-wave amplitude and exhibited significantly higher values than the DR-MSC and DR groups (p < 0.01). The flicker amplitude results showed that the DR-MSC and DR-MSC-S groups had significantly higher values than the DR group (p < 0.01). Histological examination revealed that the retinal layers were thinner in the DR-induced groups compared to the INT group, with the DR-MSC-S group showing the thickest retinal layers among them. Subconjunctival injection of sirolimus-pretreated MSCs can enhance retinal function and mitigate histological changes in the STZ-induced DR rat model.

Protein Lactylation Modification and Proteomics Features in Cirrhosis Patients after UC-MSC Treatment.

Umbilical cord mesenchymal stem cell (UC-MSC) therapy improves liver function in liver cirrhosis patients. This study aimed to elucidate the therapeutic mechanism underlying cell therapy by analyzing changes in the modification and expression of proteins 1 month post-treatment with UC-MSCs. This prospective study included 11 cirrhosis patients who received MSC injection. The laboratory indexes before and after treatment were collected to evaluate the clinical treatment effect of UC-MSCs, and the protein expression and lactylation modification in the liver were comprehensively revealed. Meanwhile, weighted gene co-expression network analysis was used to analyze the co-expression protein modules and their relationship with clinical features. The patients with liver cirrhosis showed an improvement trend after receiving UC-MSC treatment; specifically, the liver protein synthesis function was significantly improved and the coagulation function was also significantly improved. Proteomics combined with lactic acid proteomics revealed 160 lysine lactylation (Kla) sites of 119 proteins. Functional analysis showed that the lactylation-modified proteins were enriched in the pathway of glucose and other substances' metabolism, and many key enzymes of glycolysis and gluconeogenesis were lactated. UC-MSC therapy has a certain clinical effect in the treatment of liver cirrhosis and may act by regulating material metabolism, because the lactylation protein points to energy metabolism.

Immunohistochemical Study of Macrophages of Sciatic Rat Nerve after Damage and Subperineural Injection of Mesenchymal Stem Cells

The dynamics of the processes of Wallerian degeneration in the Wistar-Kyoto rat sciatic nerve after injury (ligation, 40 s) was studied.The density of Iba-1+ macrophages and the state of myelin fibers stained with Luxol strong blue in the distal segment of the nerve at different times after injury were studied. Parts of rats were subperineurally transplanted with MSCs from the bone marrow of Wistar-Kyoto rats. It was shown that the highest distribution density of macrophages in the distal segment of the nerve was observed 7 days after surgery. The use of cell therapy leads to a decrease in the number of macrophages during this period and to a delay in the demyelination of damaged nerve fibers. Sixty days after the operation, the macrophage population density and the number of remyelinated regenerating nerve fibers of the distal nerve segment did not differ in control (ligature) and experimental (ligature and MSC injection) animals. The molecular mechanisms of the noted changes in the early stages after injury require further research.

Induction of Corneal Endothelial-like Cells from Mesenchymal Stem Cells of the Umbilical Cord

Because of the limited differentiation capacity of human corneal endothelial cells (CECs), stem cells have emerged as a potential remedy for corneal endothelial dysfunction (CED). This study aimed to demonstrate the differentiation of human umbilical cord-derived mesenchymal stem cells (UC-MSCs) into CECs and to investigate the efficacy of MSC-induced CEC injection into the anterior chamber in a rabbit model of CED. Human UC-MSCs were differentiated into CECs using medium containing glycogen synthase kinase 3β inhibitor and two types of Rho-associated protein kinase inhibitors. In the MSC-induced CECs, CEC-specific proteins were identified through immunohistochemistry and changes in CEC-specific gene expressions over time were confirmed through quantitative RT-PCR. When MSC-induced CECs were injected into a rabbit model of CED, corneal opacity and neovascularization were improved compared with the non-transplanted control or MSC injection group. We also confirmed that MSC-induced CECs were well engrafted as evidenced by human mitochondrial DNA in the central cornea of an animal model. Therefore, we demonstrated the differentiation of UC-MSCs into CECs in vitro and demonstrated the clinical efficacy of MSC-induced CEC injection, providing in vivo evidence that MSC-induced CECs have potential as a treatment option for CED.

Assessment of clinical, biochemical, and radiological outcomes following intra-articular injection of Wharton jelly-derived mesenchymal stromal cells in patients with knee osteoarthritis: A prospective clinical study.

The aim of the present study was to perform clinical, biochemical, and radiological evaluation of the efficacy of mesenchymal stem cells derived from Wharton jelly (WJ) present within the human umbilical cord in the treatment of knee osteoarthritis. Between 2018 and 2019, 10 patients with knee osteoarthritis for whom the conservative treatment was not beneficial were included in the study. Patients were clinically, radiologically, and biochemically evaluated before treatment initiation. Thereafter, the patients were intra-articularly injected using a solution containing 1 × 108 WJ-derived MSCs. Evaluations were performed on day 21 (V1) and 42 (V2) and month 3 (V3), 6 (V4), and 12 (V5) after the procedure. At 1-year post-injection, visual analogue scale, Western Ontario and McMaster Universities Osteoarthritis Index, and Lequesne scores of patients were lower than those observed during the initial evaluation, whereas the mean 36-Item Short Form Health Survey score was higher. Cartilage thicknesses were found to be increased in all regions except in the medial femur, medial posterior femur, lateral posterior femur, and lateral posterior tibia regions in magnetic resonance imaging. A significant increase was observed in tumor necrosis factor-alpha, interleukin-1β, adiponectin, resistin, and interleukin-6 levels compared with pre-injection values. The leptin levels at 6-month and 1-year controls were lower than the pre-injection levels, and the decrease observed at 6 months was significant. In patients with knee osteoarthritis, intra-articular WJ-derived MSC injection causes significant pain reduction, satisfactory functional improvement, and increased patient satisfaction following a 1-year follow-up. These clinical improvements were supported by magnetic resonance images, along with changes in adiponectin and leptin levels in synovial fluid.Level of evidence: IV.

Abstract 3152: IFN-gamma stimulated cryopreserved mesenchymal stromal cells for treatment of radiation induced xerostomia

Abstract Purpose/Objectives: There is a critical need for a treatment that will safely and effectively alleviate radiation-induced xerostomia (RIX). Head and neck radiation results in hyposalivation and altered sialochemistry which patients experience as xerostomia. We performed a preclinical and a pilot clinical study to determine if IFN-ɣ stimulated marrow-derived mesenchymal stromal cells (MSC(M)) from HNC patients could function as a source of autologous cells for the treatment of RIX and as a tool in preclinical murine studies of RIX. Materials/Methods: Bone marrow aspirates from HNC patients previously treated with chemoradiation were obtained (IRB #2019-0497, NCT 04007081). MSC(M)s were isolated from bone marrow. MSC(M) were expanded in culture, surface marker expression was confirmed via flow cytometry, stimulated with IFN-ɣ, and cryopreserved. Thawed MSC(M)s were profiled to evaluate their functionality after cryorecovery. Cells were tested for their ability to stimulate salivary production in a murine model of RIX by injecting 1x106 cells into the submandibular gland (SMG) one week after a single 15 Gy fraction of radiation. Efficacy was evaluated by saliva production and histology. Results: MSC(M)s from six patients were expanded to &amp;gt;20x106 cells (median 15.5, range of 8-20 days). Post-thaw cultures demonstrated robust growth, with a median doubling time of 3.1 days. Cultured cells showed an MSC(M) phenotype, positive for CD73, CD90, and CD105 and negative for CD14, CD20, CD34, or CD45. IFN-ɣ stimulated MSC(M)s had immunomodulatory potential based on increased expression of IDO, ICAM-1, PD-L1, MHC I and MHC II expression compared with non-stimulated MSC(M)s (391%, 263%, 114%, 70% and 196% percent increase respectively). In a murine model of RIX, radiation resulted in structural changes to the gland as evidenced by increased fibrosis, decreased acinar size, and immune cell infiltration. Injection of MSC(M)s to the SMG following radiation resulted in improved saliva production, a reduction in fibrosis, and an increase in the size and density of acini within the tissue compared to control. Conclusions: These data strongly support the feasibility of a first-in-human clinical trial of autologous IFN-ɣ stimulated MSC(M)s to treat RIX and the potential of using human-derived MSC(M)s in future murine studies of RIX. Citation Format: Cristina Paz, Grace Blitzer, Annemarie Glassey, Kwangok P. Nickel, Jayeeta Giri, Andrea Pennati, Daniel Robbins, Tadeas Lunga, Susan Thibeault, Jacques Galipeau, Randall Kimple. IFN-gamma stimulated cryopreserved mesenchymal stromal cells for treatment of radiation induced xerostomia [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 3152.

Effect of the Combination of Everolimus and Mesenchymal Stromal Cells on Regulatory T Cells Levels and in a Liver Transplant Rejection Model in Rats.

IntroductionMesenchymal stromal cells (MSCs) have particular properties that are of interest in organ transplantation, including the expansion of regulatory T cells (Tregs), a key factor in transplant tolerance induction. However, the most effective immunosuppressive drug to associate with MSCs has yet to be defined. Additionally, the impact of the association of everolimus with MSCs on Treg expansion, and on the induction of liver graft tolerance, has never been studied. The aim of this study was to evaluate the effects of MSCs in combination, or not, with everolimus on Treg expansion and in a model of rejection after liver transplantation (LT) in the rat.MethodsFirstly, 24 Lewis rats were assigned to 4 groups (n=6 in each group) receiving intravenous MSCs or saline injection at day (D)9 with/without subcutaneous everolimus from D0 to D14. Analysis of circulating Tregs was performed at D0, D14 and D28. In a second set of experiment, 30 Lewis rats were randomized in 3 groups 48hours after LT with a Dark Agouti rat liver: everolimus (subcutaneous for 14 days), MSCs (intravenous injection at post-operative day 2 and 9), or both everolimus and MSCs. Rejection of the liver graft was assessed by liver tests, histology and survival.ResultsIndividually, MSC infusion and everolimus promoted Treg expansion in rats, and everolimus had no negative impact on Treg expansion in combination with MSCs. However, in the LT model, injections of MSCs two and nine days following LT were not effective at preventing acute rejection, and the combination of MSCs with everolimus failed to show any synergistic effect when compared to everolimus alone.ConclusionEverolimus may be used in association with MSCs. However, in our model of LT in the rat, post-transplant MSC injections did not prevent acute rejection, and the association of MSCs with everolimus did not show any synergistic effect.

INTRAOVARIAN INJECTION OF ALLOGENEIC MESENCHYMAL STEM CELLS: FEASIBILITY AND SAFETY ASSESSMENT IN BOVINES

<h3>Background</h3> Ovum pick-up (OPU) is a technique widely used for production of bovine embryos in-vitro. However, continuous OPU can be associated with the appearance of often irreversible ovarian lesions. The possibility of using stem cell therapy for treatment of infertility both in animals and in humans is currently under investigation, but the safety of intraovarian infusion of stem cells in bovines has not been established at this point. Therefore, in the present study we determined the feasibility and safety of intraovarian application of allogeneic MSC derived from adipose tissue of healthy cows. <h3>Methods</h3> Two OPU procedures were executed 15 days apart. Immediately following the second OPU, 2.5 million allogeneic MSCs were injected to the ovarian cortex of healthy nelore (n=5) and girolando (N=5) cows. The animals were subsequently evaluated by ultrasonography and clinical examination at 24, 48 and 72 hs post MSC injection. At 15, 30 and 45 days post MSC injection, new OPU procedures were executed and the number of viable oocytes collected, and rate of embryo production were determined. <h3>Results</h3> No clinical nor ultrasonographic alterations were detected in treated animals. Furthermore, similar numbers of viable oocytes, embryos produced, and rate of embryo production before and after MSC application were observed. <h3>Conclusion</h3> Based on these data, it can be concluded that the intra-ovarian application of 2.5 million adipose-derived MSC is safe. Future steps include the MSC treatment of individuals which present ovarian degeneration or lesions. <h3>Financial support</h3> This work was supported by CNPq, CAPES, FAPDF, FAPESP and Universidade of Brasilia.

Mesenchymal stem cells cultured in serum-free medium ameliorate experimental peritoneal fibrosis

BackgroundMesenchymal stem cells (MSCs) provide potential treatments for peritoneal fibrosis. However, MSCs cultured in media containing serum bring risks of infection and other problems. In this study, we compared the effect of human MSCs in serum-free medium (SF-MSCs) on peritoneal fibrosis with that of MSCs cultured in medium containing 10% fetal bovine serum (10%MSCs).MethodsPeritoneal fibrosis was induced by intraperitoneally injecting 0.1% chlorhexidine gluconate (CG). SF-MSCs or 10%MSCs were intraperitoneally administered 30 min after the CG injection. Ten days after the CG and MSC injections, we performed histological analyses and peritoneal equilibrium testing. In the in vitro experiments, we used transforming growth factor (TGF)-β1-stimulated human peritoneal mesothelial cells incubated in conditioned medium from MSCs to examine whether the SF-MSCs showed enhanced ability to produce antifibrotic humoral factors.ResultsHistological staining showed that the SF-MSCs significantly suppressed CG-induced cell accumulation and thickening compared with that of the 10%MSCs. Additionally, the SF-MSCs significantly inhibited mesenchymal cell expression, extracellular matrix protein deposition and inflammatory cell infiltration. Peritoneal equilibration testing showed that compared with administering 10%MSCs, administering SF-MSCs significantly reduced the functional impairments of the peritoneal membrane. The in vitro experiments showed that although the conditioned medium from MSCs suppressed TGF-β1 signaling, the suppression did not significantly differ between the SF-MSCs and 10%MSCs.ConclusionsSerum-free culture conditions can enhance the antifibrotic abilities of MSCs by suppressing inflammation. Administering ex vivo expanded SF-MSCs may be a potential therapy for preventing peritoneal fibrotic progression.

Effects of Early MSC Intervention on Preventing the Streptozotocin-Induced T1DM Progression in Mice

Type 1 diabetes mellitus is characterized by progressive pancreatic β-cells failure and progressive autoimmunity. It is difficult to diagnose T1DM and to prevent the pancreatic β-cells destruction because of the undetectable pancreatic β-cell necrosis and abnormal autoimmunity. Here, we built streptozotocin-induced T1DM mouse model and performed MSC injection at the early stage of T1DM. We found that MSC infusion displayed enhanced effects on reducing the pathological damage and improving the survival quality. Moreover, the delivery of MSCs inhibited Th1 cell polarization and downregulated the Th1 subset ratio. The immunomodulatory mechanism of MSC was further investigated. Real-time PCR and ELISA assays demonstrated that IFN-γ expression at both mRNA and protein level in MSC infusion T1DM mice was downregulated, partially regulated by MSC-exosome-derived miR-148a-3p. Taken together, this early therapeutic strategy may improve the clinical efficacy of MSC-based therapy in T1DM.

Strategies to improve Adipose Mesenchymal Stromal Cell Therapeutic Effect: Application to pelvic radiotherapy side effects

Background & Aim Healthy tissues surrounding pelvic tumours may be impaired during radiotherapy (RT) and could lead to chronic gastrointestinal complications with substantial mortality. Injection of Adipose-derived Mesenchymal Stromal Cells (Ad-MSC) represents a promising therapeutic strategy. However, many stem cell clinical trials do not confer expected beneficial effect, suggesting a real need to accelerate research towards the successful clinical application. We hypothesized that heparan sulfate (HS)-mimetic injections that restore the extracellular matrix network and enhance the biological activity of growth factors, associated with local injection of MSC protected in a hydrogel that improves cell engraftment and cell survival, could improve the therapeutic benefit of MSC treatment. Methods, Results & Conclusion We used an experimental model of radiation proctitis developed in rats that reproduces severe colonic mucosal damages and fibrosis similar to those observed in patients treated by radiotherapy. We tested injections of HS-m, local injection through endoscopy of Ad-MSC embedded in Si-HPMC hydrogel as well as combinations of these various treatments. The therapeutic benefit was evaluated by endoscopy, histology and functional parameters as epithelial barrier were also tested. We demonstrated that hydrogel loaded-Ad-MSCs were viable, able to secrete trophic factors and responsive to the inflammatory environment. In animal model, Ad-MSC+Si-HPMC improve colonic epithelial structure and hyperpermeability. This therapeutic benefit is associated with greater engraftment of Si-HPMC-embedded Ad-MSCs in the irradiated colonic mucosa. We demonstrated that combination of HS-m to hydrogel-embedded MSC treatment enhances the therapeutic benefit of MSC therapy alone. We also demonstrated that the combined treatment favored the epithelial regenerative process. Finally, using an animal model of colonic surgery after irradiation, we demonstrated that the combined treatment improved rat survival, healing of the anastomosis and scar quality assessed by collagen deposit. In this study, we identified a new way, clinically applicable, to optimize stem-cell therapy and could be proposed to patients suffering from severe colonic defect after RT.

A novel waterjet technology for transurethral cystoscopic injection of viable cells in the urethral sphincter complex.

In a recent preclinical study, we noticed that injection of cells in the urethral sphincter by needle through a cystoscope under visual control frequently yielded in misplacement or loss of cells. We, therefore, investigated if a needle-free waterjet device delivers viable cells under defined settings, including injection volume and pressure, fluid velocity and transportation media, precisely through the urothelium and connective tissue close to the sphincter muscle without full penetration of the sphincter apparatus. Mesenchymal stromal cells (MSCs) were prepared for needle-free waterjet injections. Upon injections into liquids cell viability and yield were investigated by trypan blue dye exclusion. Upon injection into cadaveric urethral tissue samples, cells were isolated from the urethrae and expanded to prove that this novel method delivered viable cells into the tissue. MSC injections by William's needle served as controls. Waterjet injections of MSCs into isotonic cell culture medium resulted in equal or better yields of viable cells when compared with needle injections. Upon injection in urethral tissue samples, the waterjet technology facilitated fast and precise injections of viable cells through urothelial, mucosal and submucosal layers to reach the sphincter muscle. By controlling the injection pressure, loss of cells due to insufficient thrust or unintended full penetration was avoided. Needle-free waterjet injections deliver cells in the urethra faster and more precisely when compared with needle injections without compromising their viability. This is the first proof-of-concept study providing evidence that a waterjet transports viable cells precisely into the targeted tissue.

Combination therapies enhance immunoregulatory properties of MIAMI cells

BackgroundMesenchymal stromal cells (MSCs), adult stromal cells most commonly isolated from bone marrow (BM), are being increasingly utilized in various therapeutic applications including tissue repair via immunomodulation, which is recognized as one of their most relevant mechanism of action. The promise of MSC-based therapies is somewhat hindered by their apparent modest clinical benefits, highlighting the need for approaches that would increase the efficacy of such therapies. Manipulation of cellular stress-response mechanism(s) such as autophagy, a catabolic stress-response mechanism, with small molecules prior to or during MSC injection could improve MSCs’ therapeutic efficacy. Unfortunately, limited information exists on how manipulation of autophagy affects MSCs’ response to inflammation and subsequent immunoregulatory properties.MethodsIn this study, we exposed BM-MSC precursor cells, “marrow-isolated adult multilineage inducible” (MIAMI) cells, to autophagy modulators tamoxifen (TX) or chloroquine (CQ), together with IFN-γ. Exposed cells then underwent RNA sequencing (RNAseq) to determine the effects of TX or CQ co-treatments on cellular response to IFN-γ at a molecular level. Furthermore, we evaluated their immunoregulatory capacity using activated CD4+ T cells by analyzing T cell activation marker CD25 and the percentage of proliferating T cells after co-culturing the cells with MIAMI cells treated or not with TX or CQ.ResultsRNAseq data indicate that the co-treatments alter both mRNA and protein levels of key genes responsible for MSCs’ immune-regulatory properties. Interestingly, TX and CQ also altered some of the microRNAs targeting such key genes. In addition, while IFN-γ treatment alone increased the surface expression of PD-L1 and secretion of IDO, this increase was further enhanced with TX. An improvement in MIAMI cells’ ability to decrease the activation and proliferation of T cells was also observed with TX, and to a lesser extent, CQ co-treatments.ConclusionAltogether, this work suggests that both TX and CQ have a potential to enhance MIAMI cells’ immunoregulatory properties. However, this enhancement is more pronounced with TX co-treatment.

Mesenchymal stem cells and treadmill training enhance function and promote tissue preservation after spinal cord injury

Spinal cord injury (SCI) is considered a serious neurological disorder that can lead to severe sensory, motor and autonomic deficits. In this work, we investigated whether cell therapy associated with physical activity after mouse SCI could promote morphological and functional outcomes, using a lesion model established by our group. Mesenchymal stem cells (8 × 105 cells/2 µL) or DMEM (2 µL), were injected in the epicenter of the lesion at 7 days after SCI, and the mice started a moderate treadmill training 14 days after injury. Functional assessments were performed weekly up to 8 weeks after injury when the morphological analyses were also performed. Four injured groups were analyzed: DMEM (SCI plus DMEM injection), MSCT (SCI plus MSC injection), DMEM + TMT (SCI plus DMEM injection and treadmill training) and MSCT + TMT (SCI plus MSC injection and treadmill training). The animals that received the combined therapy (MSCT + TMT) were able to recover and maintained the better functional results throughout the analyzed period. The morphometric analysis from MSCT + TMT group evidenced a larger spared white matter area and a higher number of preserved myelinated fibers with the majority of them reaching the ideal G-ratio values, when compared to other groups. Ultrastructural analysis from this group, using transmission electron microscopy, showed better tissue preservation with few microcavitations and degenerating nerve fibers. Also, this group exhibited a significantly higher neurotrophin 4 (NT4) expression as compared to the other groups. The results provided by this study support the conclusion that the association of strategies is a potential therapeutic approach to treat SCI, with the possibility of translation into the clinical practice.

MSC-Derived Exosome Promotes M2 Polarization and Enhances Cutaneous Wound Healing.

Mesenchymal stem cell transplantation (MSCT) promotes cutaneous wound healing. Numerous studies have shown that the therapeutic effects of MSCT appear to be mediated by paracrine signaling. However, the cell-cell interaction during MSCT between MSCs and macrophages in the region of cutaneous wound healing is still unknown. In this study, early depletion of macrophages delayed the wound repair with MSC injection, which suggested that MSC-mediated wound healing required macrophages. Moreover, we demonstrated that systemically infused bone marrow MSCs (BMMSCs) and jaw bone marrow MSCs (JMMSCs) could translocate to the wound site, promote macrophages toward M2 polarization, and enhance wound healing. In vitro coculture of MSCs with macrophages enhanced their M2 polarization. Mechanistically, we found that exosomes derived from MSCs induced macrophage polarization and depletion of exosomes of MSCs reduced the M2 phenotype of macrophages. Infusing MSCs without exosomes led to lower number of M2 macrophages at the wound site along with delayed wound repair. We further showed that the miR-223, derived from exosomes of MSCs, regulated macrophage polarization by targeting pknox1. These findings provided the evidence that MSCT elicits M2 polarization of macrophages and may accelerate wound healing by transferring exosome-derived microRNA.

P12.10 Treatment of pharmacoresistent epilepsy by combining stereotactic destruction and authologous mesenchymal stem cells

Abstract BACKGROUND Existing anti-epileptic drugs (AED) have limited efficiency in many patients, necessitating the search for alternative approaches such as stereotactic radiosurgery (SRS) and followed by stem cell therapy to improve results of previous treatment. MATERIAL AND METHODS From 2016 to 2017, a prospective study included 6 patients with a combined pathology, a median of 56 years of age, in the past TBI - 3 patients, a solitary metastatic focus in the brain (GM) - 2 patients. The indications for stereotactic intervention were both the presence of a metastatic lesion of the GM, and the bitemporal epilepsy with generalized convulsive, complex and simple partial attacks, regardless of the presence of an organic focus on CT or MRI GM. SRS was undertaken in patients undergoing a course of anticonvulsant drug therapy in combination with other types of symptomatic therapy in the absence of therapeutic effect. The frequency of generalized convulsive seizures ranged from 2–3 to 7–10 per month, complex partial from daily to 2–3 per month. SRS was performed on a stereotactic irradiation system with conical “BrainLab” collimators mounted on a linear CLINAC accelerator and allowing the session of SRS arc arches. Total dose was 12–30 Gy in isocenter, 1 fraction. After 2–3 monthes from SRS the patients received AED supplemented with single intravenous administration of undifferentiated autologous MSC (target dose of 1 × 106 cells/kg), followed by a single intrathecal injection of neurally induced autologous MSC (target dose of 0.1 × 106 cells/kg). RESULTS duration of epilepsy at the time of surgery ranged from 3 to 42 years. Cessation of attacks after 2–3 months after SRS with followed MSC therapy in 2 out of 6 patients was achieved remission (no seizures for one year and more), and 3 patients became responders to AEDs additionally, reduction of the pathological EEG pattern (disappearance of beta focusing, reduction of theta2-index to 23.6). Persistent clinical onco- and neurological remission 18 months. Reduction of the dose of enkorata-chrono - 3 patients, complete abolition of anticonvulsant therapy - 2 patients. MSC injections were well tolerated and did not cause any severe adverse effects. CONCLUSION MSC possess unique immunomodulatory properties and are a safe and promising candidate for cell therapy in AED resistant epilepsy patients in the frame of combined treatment.

Mesenchymal stem cells overexpressing hepatocyte nuclear factor-4 alpha alleviate liver injury by modulating anti-inflammatory functions in mice

BackgroundMesenchymal stem cells (MSCs) can migrate to tissue injury sites where they can induce multipotential differentiation and anti-inflammation effects to treat tissue injury. When traditional therapeutic methods do not work, MSCs are considered to be one of the best candidates for cell therapy. MSCs have been used for treating several injury- and inflammation-associated diseases, including liver cirrhosis. However, the therapeutic effect of MSCs is limited. In some cases, the anti-inflammatory function of naïve MSCs is not enough to rescue tissue injury.MethodsCarbon tetrachloride (CCl4) was used to establish a mouse liver cirrhosis model. Enhanced green fluorescence protein (EGFP) and hepatocyte nuclear factor-4α (HNF-4α) overexpression adenoviruses were used to modify MSCs. Three weeks after liver injury induction, mice were injected with bone marrow MSCs via their tail vein. The mice were then sacrificed 3 weeks after MSC injection. Liver injury was evaluated by measuring glutamic-pyruvic transaminase (ALT) and glutamic oxalacetic transaminase (AST) levels. Histological and molecular evaluations were performed to study the mechanisms.ResultsWe found that HNF-4α-overexpressing MSCs had a better treatment effect than unmodified MSCs on liver cirrhosis. In the CCl4-induced mouse liver injury model, we found that HNF-4α-MSCs reduced inflammation in the liver and alleviated liver injury. In addition, we found that HNF-4α promoted the anti-inflammatory effect of MSCs by enhancing nitric oxide synthase (iNOS) expression, which was dependent on the nuclear factor kappa B (NF-κB) signalling pathway.ConclusionsMSCs overexpressing HNF-4α exerted good therapeutic effects against mouse liver cirrhosis due to an enhanced anti-inflammatory effect. Gene modification is likely a promising method for improving the effects of cell therapy.