Objective To explore the immunosuppression effects,outcomes and clinical significance of mesenchymal stem cells (MSCs) transplantation in burn treatment by comparing the levels of WBC,C-reaction protein (CRP),interferon-γ(IFN-γ),interferon-o (TNF-α),interleukin-6 (IL-6),interleukin-10 (IL-10) between control burn models and models conducting MSCs transplantation.Methods After stripping Wharton's Jelly from the neonatal umbilical cord,MSCs was cultured and expanded.Burn models were constructed in male SD rats weighted at (200± 5) g,and randomly grouped for control and MSCs transplantation.The rats in transplantation group were injected subcutaneously with hUCMSCs (1.5× 106) at 24 h after burning.The content of WBC,CRP,IFN-γ,TNF-α,IL-6,IL-10 in blood samples at 0,1,2,3,5 and 7 d after burning were detected by enzyme-linked immunosorbent assay (ELISA).The ELISA results,the wound healing rate at 7,14,21 and 28 d,as well as wound healing time were compared and analyzed statistically by ANOVA between the two groups.Results WBC in control group increased significantly at 1 and 2 d,and CRP in control group increased substantially at 2 and 3 d.IFN-% IL-6 and IL-10 levels in serum showed increase on 5 d,and TNF-α arrived at its peak value at 7 d.By contrast,WBC,CRP,TNF-α,IL-6 and IL-10 of the MSCs transplantation group showed slightly increase after burning and the differences were convinced by statistical analysis,while IFN-γ showed little difference among the two groups.The MSCs transplantation group also showed significantly higher wound healing rate at 14,21,28 d and shorter wound healing time than that of the control.Conclusions MSCs transplantation can suppress the over-inflammatory response by significantly mediating the inflammatory cytokines as WBC,CRP,TNF-α,IL-6,IL-10 in burn.IFN-γseems not affected by MSCs transplantation.MSCs would be suitable to promote wound healing and repair in burn,which is achieved not only by differentiation and paracrine,but also by subtle immunoregulation.