Abstract
Infection of human cell with human immunodeficiency virus type-1 (HIV-1) was suppressed by cellular genetic factor(s) at reverse transcription step. Although same amount of virus adsorbed on both cells, small amount of HIV-1 (IIIB strain) infected HeLa (MAGI/CCR5) cell, while large amount of HIV-1 infected HOS (GHOST/CXCR4) cell. Regulation of virus replication at postentry level by cellular factor(s) had an important role for low efficiency of HIV-1 infection to MAGI/CCR5 cell. Provirus DNA formation in MAGI/CCR5 cell was less efficient than in GHOST/CXCR4 cell. Once GHOST/CXCR4 cell was fused with MAGI/CCR5 cell, susceptibility against HIV-1 decreased. Further, HIV-1 reverse transcriptase (RT) activity was strongly inhibited by cytosolic protein, derived from MAGI/CCR5 cell, in vitro. This research cleared a certain human cell genetically carries some factor(s) which inhibits the activity of HIV-1 RT.
