可溶性 CD8α链基因克隆及序列分析

Cloning and sequencing of the solubf CD8α chain gene

可溶性 CD8抗原(sCD8)是从 CD8^+细胞分泌或脱落至细胞外的白细胞分化抗原,sCD8与免疫调控和再生障碍性贫血等疾病有着密切关系。为从膜 CD8抗原基因中获得具有编码可溶性 CD8分子的基因,我们以 CD8抗原复合体分子的主要亚基α链基因为改构对象,采用逆转录重组 PCR 方法,在基因扩增的同时进行 DNA 重组拼接,除去编码 CD8α链穿膜序列的 DNA,从而克隆出 sCD8α链基因,并对重组的sCD8α链基因进行了序列分析.sCD8α链基因的克隆为进一步研究其表达及可溶性 CD8抗原在免疫调控中的功能奠定了基础.

The human CD8 molecule consists of two chains,termed α and β termed α and β chain · Transfeetion studies have shown the expression of the CD8β gene product gene product is strict-ly dependent on the CD8α gene product and that CD8 is expressed either as an α/α homodimer or α/β heterodimer on transfectants.Soluble CD8(sCD8)molecules come from CD8+cells and take an important rule in immunology and some diseases.For the further studies on sCD8 molecule,we have amplified a new gene coding sCD8 α chain from the cell surface CD8 α gene,which the membrane—spanning sequence has been spliced off by the method of recombinant PCR.sCD8α gene was cloned into the vector of pBluescript Ⅱ and sequenced and ready for its exprission stud-ies next.