Our previous study demonstrated that beta 2-glycoprotein I (β2GPI) stimulation promotes bone marrow derived dendritic cells (BMDCs) maturation and T cell proliferation in a Toll-like receptor 4 (TLR4) dependent manner. However, β2GPI induced T cell differentiation and the role of TLR4 in this process have rarely been reported. In the present study, we focused on the differentiation of splenic T cells in β2GPI immunized Balb/c, C3H/HeN and C3H/HeJ mice. According to our results, Th2 dominated differentiation was observed in β2GPI immunized Balb/c and C3H/HeN mice than in those treated with normal saline (NS), namely the up-regulated levels of Th2 markers GATA3 and IL-4 (p?