In vitro binding and internalization of HIV envelope glycoproteins by human epidermal Langerhans cells does not require the CD4-gp120-binding site.
Langerhans cells (LC) are epidermal dendritic cells which express several surface antigens, among them the CD4 antigens. Recent data demonstrated that LC constitute target and storage cells for HIV. To better understand the interactions between HIV and LC, we investigated, in the present work, the fate of HIV envelope glycoproteins (gp120 and gp160) incubated with healthy human trypsinized LC in suspensions. After trypsin treatment, only the epitope for OKT4 appeared to be resistant on LC. In the absence of antigenic sites identified by OKT4A, Leu3a or BL4 (epitopes implicated in HIV binding), LC bound and internalized recombinant HIV gp120 or gp160. This finding supports the hypothesis that there exists at the surface of LC a second molecule which may act as an HIV receptor.
Schmitt
D
D
INSERM U. 209, URA CNRS 601, Hôpital E. Herriot, Lyon, France.
Dezutter-Dambuyant
C
C
Hanau
D
D
Kolbe
H V
HV
Kieny
M P
MP
Cazenave
J P
JP
Thivolet
J
J
D000911:Antibodies, Monoclonal / Q000276:immunology; D001665:Binding Sites; D015704:CD4 Antigens / Q000378:metabolism*; D015496:CD4-Positive T-Lymphocytes / Q000378:metabolism*; D004817:Epidermis / Q000378:metabolism*; D000939:Epitopes / Q000276:immunology; D015686:Gene Products, env / Q000378:metabolism; D015699:HIV Envelope Protein gp120 / Q000378:metabolism*; D019302:HIV Envelope Protein gp160; D006801:Humans; D066298:In Vitro Techniques; D007801:Langerhans Cells / Q000378:metabolism* / Q000473:pathology; D011498:Protein Precursors / Q000378:metabolism; D015728:Receptors, HIV / Q000378:metabolism; D014616:Vaccinia virus / Q000032:analysis
D000911:Antibodies, Monoclonal; D015704:CD4 Antigens; D000939:Epitopes; D015686:Gene Products, env; D015699:HIV Envelope Protein gp120; D019302:HIV Envelope Protein gp160; D011498:Protein Precursors; D015728:Receptors, HIV