OBJECTIVETo study the immune repair effect of umbilical cord mesenchymal stem cells (UC-MSC) on inflammatory disorders and thrombophilia state of MRL/lpr mice by detecting the expression change of peripheral blood CD4(+) CD25(+) T cells and the levels of plasma inflammatory cytokines TNF-α, IL-6 and thrombosis indicators TF, FIB.

METHODSTwenty five MRL/lpr mice were divided into control (C) group, UC-MSC one time treatment (UT1) group and UC-MSC three time treatments (UT3) group. UC-MSC cell suspension was injecled via tail vein and these mice were feeded in SPF environment. The blood samples were taken from the mice every 2 weeks after 16(th) week. FCM was used to detect the expression of CD4(+) CD25(+) T cells in peripheral blood, ELISA assay was used to detect the levels of inflammatory cytokines TNF-α, IL-6 and thrombosis indicators TF, FIB.

RESULTSThe expression of peripheral blood CD4(+) CD25(+) T cells in treatment groups increased during 16(th) to 18(th) week, dropped and tended to be stable since 20(th) week, and lower than those in control group. The levels of plasma TNF-α and IL-6 in treatment group decreased since 16(th) week and significantly lower than those in control group (P < 0.05). The levels of plasma TF and FIB in treatment group decreased since 16(th) week. The level of plasma TF in treatment group was significantly lower than those in control group (P < 0.05) since 18(th) week.

CONCLUSIONUC-MSC can repair the immune inflammatory microenvironment disorders of MRL/lpr mice through its immunomodulatory effect. UC-MSC contribute to repair of immune inflammatory thrombophilia of MRL/lpr mice.