本文采用RT PCR技术从人外周血PBMC中克隆HLA A2基因的胞外区 ,拼接上依赖BirA酶的可生物素化序列后 ,装入pET 42b (+)高效表达载体进行诱导表达。并对表达产物进行纯化与复性。结果成功地扩增出HLA A2基因并测序证实 ;构建了融合表达载体pET HLA A2 ,并获表达与纯化。为研究在原核系统中表达、纯化与复性及进一步体外构建MHC I类分子四聚体 ,探讨免疫识别机制奠定了基础。 In this study, we cloned the extracellular domain of HLA A2 gene from PBMC of human peripheral blood by RT-PCR. The biotinylated sequence of BirA enzyme was spliced ​​and inserted into pET 42b (+) high expression vector for inducing expression. The expression product was purified and refolded. Results The HLA A2 gene was successfully amplified and confirmed by sequencing. The fusion expression vector pET HLA A2 was constructed and expressed and purified. To study the expression, purification and refolding in the prokaryotic system and to further construct MHC class I tetramer in vitro, and to explore the mechanism of immune recognition.