STRUCTURE AND ORIGIN OF HIV TYPE-1 DNA IN PERSISTENTLY INFECTED B-LYMPHOBLASTOID CELL-LINES

The Epstein-Barr virus (EBV) and human immunodeficiency virus type 1 ( HIV-1) can coinfect resting B cells, leading to EBV-carrying lymphobla stoid cell lines (LCLs) persistently infected with HIV-1. LCLs establi shed from coinfected peripheral blood lymphocytes (PBLs) differed from LCLs derived from HN-l-infected cell lines, in that the majority if n ot all of the cells expressed gp120 and a high percentage produced inf ectious HIV-1 after continuous passage for 6-9 months, Restriction ana lysis of the putative HIV-1 provirus revealed that persistently infect ed LCLs carried variable copies of primarily unintegrated circular and /or linear forms of HIV-1 DNA, This extrachromosomal location is strik ingly different from that of the one to three copies of integrated pro viral DNA deleted in persistently infected T cell and monocytic cell l ines, Anti-gp120 monoclonal antibody and 3'-azido-3'-deoxythymidine (A ZT) inhibited HIV-1 expression and reduced HIV-I DNA copy number in pe rsistently infected LCLs, supporting the hypothesis that unintegrated HIV-I DNA accumulates primarily as a result of superinfection, We prop ose that the extrachromosomal location of the HIV-1 DNA contributes to the semipermissive nature of B cell infection by HIV-1.