Study on the up-regulation of expression of B7 molecules and immunogenicity of acute leukemia cells induced by cytarabine / 白血病·淋巴瘤

ABSTRACT

Objective To investigate the effects of cytarabine(Ara-C) on expression of B7 molecules and immunogenicity of acute leukemia (AL) cells. Methods The expression of B7 molecules on fresh AL ceils and on the Ara-C exposed leukemia ceils was detected by FACS cytometer. B7 mRNA in Ara-C treated HL-60 cells were detected by reverse RT-PCR. The stimulation of proliferation of allogeneic PBMC by Ara-C treated HL-60 cells was detected by MTT method. Results B7-2 was weakly expressed in four and positive in three, whereas BT-1 was positive in only one of fourty AL patiens. Ara-C significantly enhanced B7 molecules expression on AL cells. Ara-C could induce higher expression of B7 mRNAs on HL-60 cells.Ara-C treated HL-60 cells could stimulate PBMC proliferation and promote their IFN -γ production.Conclusion Fresh AL cells express low level of B7 molecules. Ara-C enhances the B7 molecules expression on AL cells. The Ara-C treated leukemia cells can significantly stimulate the proliferation of allogeneic PBMC and induce their secretion of IFN-γ.