通过Fas-FasL途径体外清除小鼠同种异体反应性T细胞

目的　通过Fas Fas配体 (FasL)途径清除小鼠同种异体反应性T细胞 (ARTC) ,为减轻异基因骨髓移植 (allo BMT)后的移植物抗宿主病探索新的手段。方法　用磁性细胞分离系统分离BALB c小鼠 (H 2 d)Sca 1+早期造血细胞 (HC) ,然后借助逆转录病毒基因转移技术对其转染外源小鼠FasL(mFasL)cDNA基因 ;扩增 1周后与异基因BAC小鼠 (H 2 d ×b)脾细胞进行单向混合淋巴细胞培养(OWMLC) 6d ,观察处理后的BAC小鼠脾细胞对Na251 CrO4标记的BALB c小鼠脾细胞的杀伤作用。结果　成功分离出BALB c小鼠Sca 1+HC ,纯度为 (89.0± 6 .1) %。BAC小鼠脾细胞与转染外源mFasL的BALB cHC以 1∶5比例共培养 6d后 ,对BALB c源脾细胞杀伤率在不同效、靶比例时均呈显著降低 (P<0 .0 1)。结论　体外反应中 ,转染外源mFasLcDNA并高表达的早期HC可清除针对自身MHC抗原的ARTC。

Selected elimination of mouse alloreactive T cells by Fas-FasL passway

OBJECTIVE: To explore a new method of alleviating graft-versus-host disease (GVHD) after allogeneic bone marrow transplantation (allo-BMT) through selected elimination of mouse alloreactive T cells (ARTC) by Fas-Fas ligand (FasL) passway. METHODS: The Sca-1(+) early hematopoietic cells (EHCs) were isolated from BALB/c mouse (H-2(d)) bone marrow mononuclear cells (BMMC) by using a high gradient magnetic cell sorting system (MACS), then transferred with exogenous mouse FasL (mFasL) gene by retroviral gene transfecting technique. Afterward the transduced EHCs were expanded in vitro for one week followed by coculture with the spleen cells from BAC mouse (H-2(d) x b) as one-way mixed lymphocyte culture (OWMLC) for 6 days, then the cytotoxicity of treated BAC mouse spleen cells against Na(2)(51)CrO(4) labelling spleen cells from BALB/c mouse was observed. RESULTS: The Sca-1(+) EHCs were successfully isolated by MACS, with a purity of (89.0 +/- 6.1)%. After transferred with exogenous mFasL gene and expanded for one week, the transferred EHCs in the 6 day OWMLC with the spleen cells from BAC mouse at a ratio of five to one resulted in an obvious inhibition of the BAC mouse spleen cells cytotoxicity against the BALB/c mouse spleen cell at different effector/target ratios as compared to the control group (P < 0.01). CONCLUSION: The higher exogenous mFasL-expressing mouse EHCs can deplete ARTC against their own major histocompatibility complex (MHC) antigens in vitro.