Long-Term Effects of Bone Marrow-Derived Mesenchymal Stem Cells in Dextran Sulfate Sodium-Induced Murine Chronic Colitis

BACKGROUND/AIMS: Bone marrow-derived mesenchymal stem cells (BM-MSCs) have shown beneficial effects in experimental colitis models, but the underlying mechanisms are not fully understood. We investigated the long-term effects of BM-MSCs, particularly in mice with chronic colitis. METHODS: Chronic colitis was induced by administering 3% dextran sulfate sodium (DSS) in a series of three cycles. BM-MSCs were injected intravenously into DSS-treated mice three times during the first cycle. On day 33, the therapeutic effects were evaluated with clinicopathologic profiles and histological scoring. Inflammatory mediators were measured with real-time polymerase chain reaction. RESULTS: Systemic infusion of BM-MSCs ameliorated the severity of colitis, and body weight restoration was significantly promoted in the BM-MSC-treated mice. In addition, BM-MSC treatment showed a sustained beneficial effect throughout the three cycles. Microscopic examination revealed that the mice treated with BM-MSCs had fewer inflammatory infiltrates, a lesser extent of inflammation, and less crypt structure damage compared with mice with DSS-induced colitis. Anti-inflammatory cytokine levels of interleukin-10 were significantly increased in the inflamed colons of BM-MSC-treated mice compared with DSS-induced colitis mice. CONCLUSIONS: Systemic infusion of BM-MSCs at the onset of disease exerted preventive and rapid recovery effects, with long-term immunosuppressive action in mice with repeated DSS-induced chronic colitis.

Mesenchymal Stem Cell Transfer Suppresses Airway Remodeling in a Toluene Diisocyanate-Induced Murine Asthma Model

PURPOSE: Severe asthma is characterized by high medication requirements to maintain good disease control or by persistent symptoms despite high medication use. The transfer of bone marrow-derived mesenchymal stem cells (BMDMSCs) to the injured lungs is a possible treatment for severe asthma. This study investigated the therapeutic effects of BMDMSCs in airway remodeling and inflammation in an experimental toluene diisocyanate (TDI)-induced asthma animal model of severe asthma. METHODS: BMDMSCs were transferred into rats after TDI inhalation. Bronchoalveolar lavage (BAL) cell profiles, histological changes including an inflammatory index and goblet cell hyperplasia, and the airway response to methacholine using plethysmography were analyzed. Smooth muscle actin (SMA) and proliferating cell nuclear antigen (PCNA) protein expression were observed in lung tissue using immunohistochemical staining. The collagen content was measured in lung tissue sections and lung extracts using Masson's trichrome staining and an immunoassay kit. RESULTS: The numbers of inflammatory cells in BAL fluid, histological inflammatory index, airway response to methacholine, number of goblet cells, and amount of collagen were increased in TDI-treated rats compared with sham rats (P=0.05-0.002). BMDMSC transfer significantly reduced the TDI-induced increase in the inflammatory index and numbers of eosinophils and neutrophils in BAL fluid to levels seen in sham-treated rats (P<0.05). BMDMSC transfer significantly reduced the number of goblet cells, collagen deposition, and immune staining for SMA and PCNA with concomitant normalization of the airway response to methacholine. CONCLUSIONS: The systemic transfer of BMDMSCs effectively reduced experimental TDI-induced airway inflammation and remodeling and airway hyperreactivity.