Efficiency of mesenchymal stem cells in the mice with primary immune thrombocytopenia and its mechanism

Objective To investigate the efficiency of mesenchymal stem cells (MSCs) in the mice with primary immune thrombocytopenia (ITP) and its mechanism.Method ITP was induced by daily intraperitoneal injection of anti-platelet membrane CD41 antibody into BALB/c mice,then 20 cases were enrolled as observation group and-20 cases as control group at the same time.2 × 107 MSCs were injected into each mouse in observation group through the tail vein.After 14 days,the number of blood platelets was counted in two groups,and the absolute number of myeloid DC (Lin-HLA-DR+CD11c+ cells) and the expression of CD80 and CD86 on mDC of ITP patients were anylyzed by using flow cytometry.The levels of INF-γ,IL-2,IL-4 and IL-10 were detected by using ELASA.Results The number of blood platelets in observation group [(623± 78.9) × 1 09/L] was significantly greater than that in control group [(288 ± 87.8) × 109/L] (P＜0.05).The absolute number of myeloid DC in observation group [(16.24± 9.97)/ml] was significantly less than that in control group [(29.32±13.21)/ml] (P＜0.05).The expression of CD80 and CD86 on mDC in observation group [(2.31 ±1.26)％ and (46.25 ± 20.21)％ respectively] were significantly lower than that in control group [(6.27 ± 3.31) ％ and (62.21 ± 16.41) ％ respectively].The concentrations of Th1 type cytokins INF-γ and IL 2 in observation group [(3.1 ± 1.7) pg/ml and (3.2 ± 2.1) pg/ml,respectively] were significantly lower than those in control group [(10.3 ± 4.8) pg/ml and (16.3 ± 5.7) pg/ml respectively] (P＜0.05),but those of Th2 type cytokins IL-4 and IL-10 in observation group [(88.6 ± 15.2) pg/ml and (38.3 ± 11.8) pg/ml respectively] were significantly higher than those in control group [(32.7 ± 5.7) pg/ml and (22.1 ± 3.4) pg/ml respectively] (P＜0.05).Conclusion MSCs are associated with a favorable efficiency in mice with primary ITP,which was related with the suppression of Th1-dominant response due to the enhanced function of DC. Key words: Mice;  Mesenchymal stem cells;  Immune thrombocytopenia; TH 1 cells; Dentritic cell