Proteinase-resistant factors in human erythrocyte membranes mediate CD4-dependent fusion with cells expressing human immunodeficiency virus type 1 envelope glycoproteins.
Murine CD4+ cells are resistant to human immunodeficiency virus type 1 (HIV-1) entry and to fusion with cells expressing HIV-1 envelope glycoproteins (Env). The role of human-specific factors in Env/CD4-mediated fusion is shown by the ability of transient cell hybrids formed between CD4+ murine cells and human HeLa cells to fuse with Env+ cells. Fusion events were observed when other human cells, including erythrocytes, were substituted for HeLa cells in the hybrids. Experiments with erythrocyte ghosts showed that the factors allowing Env/CD4-mediated fusion are located in the plasma membrane. These factors were fully active after extensive digestion of erythrocytes with proteinase K or pronase. Nonprotein components of human plasma membranes, possibly glycolipids, could therefore be required for Env/CD4-mediated fusion and virus entry.
Dragic
T
T
Institut National de la Santé et de la Recherche Médicale U332, Institut Cochin de Génétique Moléculaire, Paris, France.
Picard
L
L
Alizon
M
M
D016475:3T3 Cells; D000818:Animals; D015704:CD4 Antigens / Q000502:physiology*; D002460:Cell Line; D019286:Endopeptidase K; D004910:Erythrocyte Membrane / Q000502:physiology*; D015686:Gene Products, env / Q000502:physiology*; D015497:HIV-1 / Q000502:physiology*; D006801:Humans; D004915:Leukemia, Erythroblastic, Acute / Q000473:pathology; D008561:Membrane Fusion; D051379:Mice; D011402:Pronase / Q000494:pharmacology; D012697:Serine Endopeptidases / Q000494:pharmacology
D015704:CD4 Antigens; D015686:Gene Products, env; D012697:Serine Endopeptidases; D019286:Endopeptidase K; D011402:Pronase