ABSTRACT
A crucial role in eliciting anti-tumor immunity of costimulatory molecule CD80(B7-1) has been demonstrated by animal experimental studies.In this paper, CD80 expression in human tumor cell lines and EBV-transformed B cell was detected using RT-PCR and FACS methods. The results showed that CD80 expression of Raji and EBV-transformed B cell was positive but that of 3AO,MCF-7,MDA-453,MKN-45, Hela was negative. We have constructed retroviral vector CD80-pLN,transfected package cell PA317, screened high titer rctrovirus supernatant then infected human tumor cell lines and gained CD80 positive tumor cell clones. With pre-and post-CD80-transfected human breast carcinoma cell line MDA-453,the upregulated expression of ICAM-I, HLA class I molecule was observed, but the expression of HLA class II molecule wasn't changed.