The leukocyte adhesion glycoprotein CD18 participates in HIV-1-induced syncytia formation in monocytoid and T cells.
mAb 60.3 and IB4 to CD18, the common beta-subunit of the human leukocytic cell adhesion molecule family, efficiently inhibit syncytium formation induced by the interaction of HIV type 1 (HIV-1)-infected monocytoid cells and CD4+ T cells. The antibodies also interfere with cellfree HIV-1 infection of U-937 clone 16 cells. Virus-induced aggregation of these cells and the subsequent syncytia formation leading to massive cell death are efficiently blocked, and the number of infected cells remains at a very low level, 2 to 5%, for the entire culture period. However, anti-CD18 mAb do not inhibit binding of the viral envelope glycoprotein gp120 to the cell surface receptor CD4. The results indicate participation of CD18, or of the protein complex CD11a-c/CD18, in addition to CD4, in the infection and cytopathic effect of HIV-1. They also suggest that intercellular adhesion contributes to virus transmission from cell to cell and may be an important mechanism for virus spreading.
Valentin
A
A
Department of Virology, Karolinska Institute, Stockholm, Sweden.
Lundin
K
K
Patarroyo
M
M
Asjö
B
B
D000911:Antibodies, Monoclonal; D015703:Antigens, CD / Q000502:physiology*; D018821:CD18 Antigens; D015496:CD4-Positive T-Lymphocytes / Q000166:cytology* / Q000382:microbiology; D002448:Cell Adhesion; D002459:Cell Fusion; D003588:Cytopathogenic Effect, Viral; D015658:HIV Infections / Q000473:pathology; D015497:HIV-1 / Q000472:pathogenicity*; D007158:Immunologic Techniques; D066298:In Vitro Techniques; D009000:Monocytes / Q000166:cytology* / Q000276:immunology; D016028:Receptors, Leukocyte-Adhesion / Q000502:physiology*
D000911:Antibodies, Monoclonal; D015703:Antigens, CD; D018821:CD18 Antigens; D016028:Receptors, Leukocyte-Adhesion