To examine the effect of UC-MSCs on CD4+T cells from ITP patients, we treated CD4+T cells with UC-MSCs in the absence or presence of stimuli (CD3/CD28) and found that CD4+T cells could not proliferate culturing with UC-MSCs or in the absence of stimuli (Figures 3(a) and 3(c)). Here, CD28 is linked to autoimmune thrombocytopenic purpura.