Allogeneic Marrow-derived Mesenchymal Stromal Cells Research Articles

Intravenous Autologous Bone Marrow-derived Mesenchymal Stromal Cells Delay Acute Respiratory Distress Syndrome in Swine.

Rationale: Early post injury mitigation strategies in ARDS are in short supply. Treatments with allogeneic stromal cells are administered after ARDS develops, require specialized expertise and equipment, and to date have shown limited benefit. Objectives: Assess the efficacy of immediate post injury intravenous administration of autologous or allogeneic bone marrow-derived mesenchymal stromal cells (MSCs) for the treatment of acute respiratory distress syndrome (ARDS) due to smoke inhalation and burns. Methods: Yorkshire swine (n = 32, 44.3 ± 0.5 kg) underwent intravenous anesthesia, placement of lines, severe smoke inhalation, and 40% total body surface area flame burns, followed by 72 hours of around-the-clock ICU care. Mechanical ventilation, fluids, pressors, bronchoscopic cast removal, daily lung computed tomography scans, and arterial blood assays were performed. After injury and 24 and 48 hours later, animals were randomized to receive autologous concentrated bone marrow aspirate (n = 10; 3 × 106 white blood cells and a mean of 56.6 × 106 platelets per dose), allogeneic MSCs (n = 10; 6.1 × 106 MSCs per dose) harvested from healthy donor swine, or no treatment in injured control animals (n = 12). Measurements and Main Results: The intravenous administration of MSCs after injury and at 24 and 48 hours delayed the onset of ARDS in swine treated with autologous MSCs (48 ± 10 h) versus control animals (14 ± 2 h) (P = 0.004), reduced ARDS severity at 24 (P < 0.001) and 48 (P = 0.003) hours, and demonstrated visibly diminished consolidation on computed tomography (not significant). Mortality at 72 hours was 1 in 10 (10%) in the autologous group, 5 in 10 (50%) in the allogeneic group, and 6 in 12 (50%) in injured control animals (not significant). Both autologous and allogeneic MSCs suppressed systemic concentrations of TNF-α (tumor necrosis factor-α). Conclusions: The intravenous administration of three doses of freshly processed autologous bone marrow-derived MSCs delays ARDS development and reduces its severity in swine. Bedside retrieval and administration of autologous MSCs in swine is feasible and may be a viable injury mitigation strategy for ARDS.

Local administration of allogeneic or autologous bone marrow-derived mesenchymal stromal cells enhances bone formation similarly in distraction osteogenesis

Background aimsDistraction osteogenesis (DO) is a surgical technique to promote bone regeneration that requires a long time for bone healing. Bone marrow-derived mesenchymal stromal cells (MSCs) have been applied to accelerate bone formation in DO. Allogeneic MSCs are attractive, as they could be ready to use in clinics. Whether allogeneic MSCs would have an effect similar to autologous MSCs with regard to promoting bone formation in DO is still unknown. This study compares the effect of autologous MSCs versus allogeneic MSCs on bone formation in a rat DO model. MethodsRat bone marrow-derived MSCs were isolated, characterized and expanded in vitro. Adult rats were subjected to right tibia transverse osteotomy. On the third day of distraction, each rat received one injection of phosphate-buffered saline (PBS), autologous MSCs or allogeneic MSCs at the distraction site. Tibiae were harvested after 28 days of consolidation for micro-computed tomography examination, mechanical test and histological analysis. ResultsResults showed that treatment with both allogeneic and autologous MSCs promoted bone formation, with significantly higher bone mass, mechanical properties and mineral apposition rate as well as expression of angiogenic and bone formation markers at the regeneration sites compared with the PBS-treated group. No statistical difference in bone formation was found between the allogeneic and autologous MSC treatment groups. ConclusionsThis study indicates that allogeneic and autologous MSCs have a similar effect on promoting bone consolidation in DO. MSCs from an allogeneic source could be used off-the-shelf with DO to achieve early bone healing.

TGF-β2 decreases surface expression of MHC I and MHC II on equine bone marrow-derived mesenchymal stromal cells.

Abstract Allogeneic bone marrow-derived mesenchymal stromal cells (MSCs) are a promising cell source for treatment of inflammatory diseases, but elicit immune responses in vivo due to recipient recognition of mismatched Major Histocompatibility Complex (MHC) molecules. The purposes of this study were to evaluate the effectiveness of TGF-β2 in decreasing and stabilizing MHC expression on equine bone marrow-derived MSCs before and after IFN-γ stimulation. FACS analysis showed that MSCs treated with 1, 5, or 10 ng/ml of TGF-β2 had significantly reduced MHC I expression. MHC I expression levels on TGF-β2-treated MSCs were also quantified and determined to be similar to fetal fibroblasts. MHC II expression in two positive animals was greatly reduced compared to untreated MSCs. MSCs pre-treated and continuously treated with 1 ng/ml TGF-β2 had significantly lower MHC I expression following stimulation with IFN-γ for 72 hours compared with untreated. Continuously treated MSCs that were baseline positive for MHC II had significantly lower MHC II expression following IFN-γ stimulation, but there was no significant difference in MHC II expression between TGF-β2-treated and untreated MHC II-negative MSCs after IFN-γ stimulation. These results indicate TGF-β2 treatment has significant promise for reducing recipient immune recognition of MHC-mismatched molecules on allogeneic MSCs, but further work is needed to maintain MHC expression stability.

Allogeneic Bone Marrow–Derived Mesenchymal Stromal Cells Promote Healing of Refractory Perianal Fistulas in Patients With Crohn’s Disease

Patients with perianal fistulizing Crohn's disease have a poor prognosis because these lesions donot heal well. We evaluated the effects of local administration of bone marrow-derived mesenchymal stromal cells (MSCs) to these patients from healthy donors in a double-blind, placebo-controlled study. Twenty-one patients with refractory perianal fistulizing Crohn's disease were randomly assigned to groups given injections of 1× 10(7) (n= 5, group 1), 3× 10(7) (n= 5, group 2), or 9× 10(7) (n= 5, group 3) MSCs, or placebo (solution with no cells, n= 6), into the wall of curettaged fistula, around the trimmed and closed internal opening. The primary outcome, fistula healing, was determined by physical examination 6, 12, and 24 weeks later; healing wasdefined as absence of discharge and <2 cm of fluid collection-the latter determined by magnetic resonance imaging at week 12. All procedures were performed at Leiden University Medical Center, The Netherlands, from June 2012 through July2014. No adverse events were associated withlocal injection of any dose of MSCs. Healing at week 6 wasobserved in 3 patients in group 1 (60.0%), 4 patients in group 2 (80.0%), and 1 patient in group 3 (20.0%), vs 1 patient in the placebo group (16.7%) (P= .08 for group 2 vs placebo). At week 12, healing was observed in 2 patients in group 1 (40.0%), 4 patients in group 2 (80.0%), and 1 patient in group3 (20.0%), vs 2 patients in the placebo group (33.3%); theseeffects were maintained until week 24 and even increased to 4 (80.0%) in group 1. At week six, 4 of 9 individual fistulas had healed in group 1 (44.4%), 6 of 7 had healed in group 2 (85.7%), and 2 of 7 had healed in group 3 (28.6%) vs 2 of 9 (22.2%) in the placebo group (P= .04 for group 2 vs placebo). At week twelve, 3 of 9 individual fistulas had healed in group 1 (33.3%), 6 of 7 had healed in group 2 (85.7%), 2 of 7 had healed in group 3 (28.6%), and 3 of 9 had healed in the placebo group (33.3%). These effects were stable through week 24 and even increased to 6 of 9 (66.7%) in group 1 (P= .06 group 2 vs placebo, weeks 12 and 24). Local administration of allogeneic MSCs was not associated with severe adverse events in patients with perianal fistulizing Crohn's disease. Injection of 3× 10(7) MSCs appeared to promote healing of perianal fistulas. ClinicalTrials.gov ID NCT01144962.

Adoptive transfer of mesenchymal stromal cells accelerates intestinal epithelium recovery of irradiated mice in an interleukin-6-dependent manner

Apoptosis of radiosensitive cells in the bone marrow and gut is a serious, at times life-threatening, complication arising from radiation exposure. We investigated whether adoptive transfer of allogeneic bone marrow-derived mesenchymal stromal cells (MSC) could exert cytoprotective and life-sparing effects in a mouse model of sublethal total body irradiation (TBI). We demonstrated that a single intraperitoneal injection of C57Bl/6 MSC given to major histocompatibility complex (MHC)-mismatched Balb/c mice within 24 h of sublethal TBI significantly reduced mortality in a dose-dependent manner. Histologic analysis and Ki67 immunostaining of jejunum sections collected 3 and 6 days post-TBI indicated that MSC protected the gastrointestinal epithelium from TBI-induced damage and significantly accelerated recovery of the gut by stimulating proliferation of the crypt cell pool. Using interleukin-6(-/-) (IL-6) MSC, we demonstrated that IL-6 expressed by MSC played a role in gastrointestinal epithelium regeneration. Our results suggest that allogeneic MHC-mismatched MSC may be exploited to reduce gastrointestinal complications and mortality arising from ionizing radiation exposure.