A RODENT CELL-LINE PERMISSIVE FOR ENTRY AND REVERSE TRANSCRIPTION OF HUMAN-IMMUNODEFICIENCY-VIRUS TYPE-1 HAS A PREINTEGRATION BLOCK TO PRODUCTIVE INFECTION

Replication of human immunodeficiency virus type 1 (HIV-1) is restrict ed to CD4-expressing primate cells. This tropism may be due partly to the absence from nonprimate cells of a species-specific factor which h as an accessory role to CD4 during virus penetration. In this study we describe a rat B lymphocyte cell line in which there is efficient CD4 -dependent entry of HIV-1. However, this cell line has a block to prod uctive infection of HIV-1 at a stage between reverse transcription and integration. Our results demonstrate that the putative accessory fact or for HIV-1 penetration is not restricted to primate cells and that t here is a novel, uncharacterized cell-virus interaction at a stage bet ween penetration and integration.