Immunosuppressive effects of mesenchymal stem cell transplantation in rat burn models

This study is to investigate the effects of mesenchymal stem cell (MSC) transplantation in burn treatment.

Wharton's Jelly was stripped from neonatal umbilical cord, and human umbilical cord MSCs were then cultured. Burn models were constructed in male SD rats weighted at 200±5 g, and the rats were randomly divided into control and MSCs transplantation groups. The rats in transplantation group were injected subcutaneously with MSCs (2×10(6)) at 24 h after burning. Blood samples were collected at 0 d, 1 d, 2 d, 3 d, 5 d and 7 d after burning and the contents of white blood cells (WBC), C-reactive protein (CRP), interferon-γ (IFN-γ), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and interleukin-10 (IL-10 ) were detected. The wound healing rate at 7 d, 14 d, 21 d and 28 d together with the wound healing time were compared and analyzed statistically by analysis of variance (ANOVA).

WBC and CRP in control group increased significantly at 1 d and 2 d, 2 d and 3 d, respectively. IFN-γ, IL-6 and IL-10 levels in serum showed increasing till 5th day and TNF-α arrived its peak value at 7th day. By contrast, WBC, CRP, TNF-α, IL-6 and IL-10 in the MSCs transplantation group showed slight increase after burning and the differences were verified by statistically analysis. IFN-γ showed no significant difference between the two groups. MSCs transplantation group showed significantly higher wound healing rate at 14 d, 21 d, 28 d and showed shorter wound healing time than control.

MSCs transplantation could suppress secondary inflammatory reaction by lowering inflammatory cytokines after burning, thus promoting wound healing and scald repair in burn animal model.