Regions of the CD4 molecule not involved in virus binding or syncytia formation are required for HIV-1 infection of lymphocytes.
Cell surface-expressed CD4 binds to the envelope glycoprotein of HIV-1 and mediates syncytia formation through interacting with membrane expressed HIV-1 gp120. Further possible roles of the CD4 molecule in the process of cell infection by HIV-1 remain poorly understood. In our study we describe two mAb that recognize the V3/V4 domain of the CD4 molecule. Although these mAb do not inhibit gp120-CD4 binding or HIV-1-induced syncytia formation, they inhibit HIV-1 infection of human PBL. These findings suggest that discrete, definable domains of the CD4 molecule may be involved in interactions after HIV-1 envelope binding that lead to virus entry into the cell.
Hasunuma
T
T
Harvard Medical School, New England Regional Primate Research Center, Southborough, MA 01772.
Tsubota
H
H
Watanabe
M
M
Chen
Z W
ZW
Lord
C I
CI
Burkly
L C
LC
Daley
J F
JF
Letvin
N L
NL
D000911:Antibodies, Monoclonal / Q000276:immunology; D001665:Binding Sites; D015704:CD4 Antigens / Q000276:immunology / Q000378:metabolism*; D002118:Calcium / Q000378:metabolism; D002459:Cell Fusion; D000939:Epitopes; D015699:HIV Envelope Protein gp120 / Q000378:metabolism; D015658:HIV Infections / Q000382:microbiology*; D015497:HIV-1 / Q000378:metabolism*; D006801:Humans; D011948:Receptors, Antigen, T-Cell / Q000502:physiology; D011994:Recombinant Proteins / Q000378:metabolism; D015398:Signal Transduction; D012995:Solubility; D013601:T-Lymphocytes / Q000382:microbiology*
D000911:Antibodies, Monoclonal; D015704:CD4 Antigens; D000939:Epitopes; D015699:HIV Envelope Protein gp120; D011948:Receptors, Antigen, T-Cell; D011994:Recombinant Proteins; D002118:Calcium