OBJECTIVETo study the relationship of Blimp-1 hypoexpression with abnormality of Treg level and pathogenesis of aplastic anemia (AA).

METHODSThe mouse model with AA was established by adminis tration of IFN-γ combined with busulfan. The samples were collected at different day establishing AA model, and the spleen Treg number was detected, the Treg cells were sorted and expression level of prdm-1 was detected.

RESULTSThe number of Tregs in mice with AA was lower than that in control mice, moreover, the level of Treg decrease positively correlated with the AA severity (r=0.805), the higher the expression level of prdm-1, the higher the ratio of Treg/lymphocytes, showing positive correlation between them (r=0.548).

CONCLUSIONBlimp-1 expression may promote the proliferation and differentiation of Treg. The hypoexpression of Blimp-1 mediates the pathogenesis of AA and promotes progression of AA through reducing the proliferation of Treg, and decreacing the number of Treg.