Human immunodeficiency virus type 2 infection and fusion of CD4-negative human cell lines: induction and enhancement by soluble CD4.
We describe human immunodeficiency type 2 (HIV-2) strains which induce cell-to-cell fusion and infect certain CD4- human cell lines. Soluble CD4 (sCD4) induces or enhances fusion by most HIV-2 strains tested. Soluble CD4-immunoglobulin G chimeras and conjugates of sCD4 and antibody to the third domain of CD4 block HIV-2 fusion of CD4- cells. We conclude that HIV-2 can enter CD4- cells via an alternative cell surface receptor to CD4. While some strains entered efficiently, others retained a dependency on an interaction with sCD4 to initiate changes in the virion envelope required for membrane fusion.
Clapham
P R
PR
Chester Beatty Laboratories, Institute of Cancer Research, London, England.
McKnight
A
A
Weiss
R A
RA
D000163:Acquired Immunodeficiency Syndrome / Q000382:microbiology*; D015704:CD4 Antigens / Q000378:metabolism*; D002459:Cell Fusion / Q000187:drug effects / Q000502:physiology*; D002460:Cell Line; D004252:DNA Mutational Analysis; D015699:HIV Envelope Protein gp120 / Q000378:metabolism; D015498:HIV-2 / Q000472:pathogenicity*; D006801:Humans; D015728:Receptors, HIV / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D012208:Rhabdomyosarcoma / Q000382:microbiology; D014407:Tumor Cells, Cultured
D015704:CD4 Antigens; D015699:HIV Envelope Protein gp120; D015728:Receptors, HIV; D011993:Recombinant Fusion Proteins