After another 40 passages, env gene and Env protein in the cells were detected by PCR, Southern-blot, IFA and Western-blot.

• 连续传40代后,分别用PCR、Southern-blot、间接免疫荧光(IFA)及Western-blot对细胞中的env基因进行了检测,并进行了抗病毒感染分析。