摘要
目的探讨白细胞介素7(IL7)对急性白血病(AL)细胞B7分子表达和免疫原性的影响。方法用流式细胞术检测AL原代白血病细胞B7分子的表达。体外用IL7诱导白血病细胞,分析其对B7分子蛋白表达的影响,进而用RTPCR检测B71和B7-2mRNA表达。MTT法检测诱导后白血病细胞对异基因外周血单个核细胞(PBMNC)的刺激作用,并用酶联免疫吸附法(ELISA)测定上清液中γ干扰素(IFNγ)含量。应用B71、B72和W6/32单抗阻断实验研究B7分子刺激PBMNC的机制。结果11例AL患者中B71弱阳性3例,B7-2弱阳性1例。IL7能显著刺激白血病细胞B7-1和B72表达,呈时间依赖性。IL7作用于HL60细胞可诱导B71和B72mRNA表达。诱导后的白血病细胞显著刺激PBMNC增殖并产生IFNγ。B71单抗和W6/32单抗可抑制白血病细胞诱导PBMNC增殖和产生IFNγ,而B7-2单抗无抑制作用。结论原代AL细胞低表达B71和B72分子。在体外,IL7通过诱导白血病细胞B71分子表达,刺激淋巴细胞增殖,使PBMNC分泌IFNγ增多,显著提高了白血病细胞的免疫原性。在共刺激分子诱导抗白血病T细胞免疫反应中,B71作用显著强于B7-2。
Objective To investigate the effects of interleukin 7 (IL-7) on B7 molecules expression and immunogenicity of acute leukemia(AL) cells. Methods The B7 molecules expression on fresh acute leukemia cells and on the IL-7 exposed leukemia cells was detected by FACScan cytometer. B7-1 and B7-2 mRNA in IL-7 treated HL-60 cells were detected by reverse transcription-PCR (RT-PCR). The stimulation of proliferation of allogeneic peripheral blood mononuclear cells (PBMNC) by IL-7 treated leukemia cells was detected by MTT method. The level of interferon-gamma (IFN-γ) secreted by the stimulated PBMNC was determined using enzyme-linked immunosorbent assays (ELISA). The blocking experiments were performed using monoclonal antibodies against B7-1, B7-2 and W6/32. Results B7-1 was weakly expressed in three, whereas B7-2 did in only one of eleven AL patients. IL-7 significantly enhanced B7 molecules expression on AL cells in a time-dependent manner. Furthermore, IL-7 could induce higher expression of B7-1 and B7-2 mRNAs on HL-60 cells. IL-7 treated leukemia cells could stimulate PBMNC proliferation and promote their IFN-γ production. Anti-B7-1 and anti W6/32 but not anti-B7-2 monoclonal antibodies significantly inhibited the stimulated PBMNC proliferation and IFN-γ secretion. Conclusion Fresh AL cells express low level of B7-1 and B7-2 molecules. IL-7 enhances the B7 molecules expression on AL cells. The IL-7-treated leukemia cells can significantly stimulate the proliferation of allogeneic PBMNC and induce their IFNγ secretion.
出处
《中华血液学杂志》
CAS
CSCD
北大核心
2005年第5期289-292,共4页
Chinese Journal of Hematology
基金
浙江省卫生厅青年人才基金资助项目(2000QN003)
