Methods The DNA fregment target to the translation initiation site of CCR5 mRNA obtained by RT - PCR from peripheral blood mononuclear cells(PBMCs)was cloned into retro-viral vector pLXSN.

• 方法 用RT-PCR从健康人外周血单个核细胞（PBMCs）中获得趋化因子受体CCR5翻译起始区的基基片段,用基因重组技术将此目的基因以正、反两个方向定向插入到逆转录病毒载体pLXSN。