HIV-1 expression in chimpanzees can be activated by CD8+ cell depletion or CMV infection.
CD8+ cell antiviral activity and cytomegalovirus (CMV) were investigated in vivo as possible cofactors influencing the outcome of HIV-1 infection. The role of CD8+ cell suppression of HIV replication was evaluated by depleting CD8+ cells in two infected chimpanzees by inoculation with monoclonal anti-CD8 antibodies. Two other infected animals were injected with chimpanzee CMV (CCMV)-infected human fibroblasts to determine if exposure to this virus would induce HIV replication. Treatment with anti-CD8 antibody resulted in recovery of virus from the CD4+ lymphocytes of one animal at 1, 4, and 6 months, and from a second animal at 1 month postinoculation. In contrast, virus had been recovered only once or not at all from these infected chimpanzees for 4 years prior to treatment. Similarly, HIV was recovered from the CD4+ cells of the two animals 2 to 3 months after inoculation of CCMV-infected fibroblasts but not after inoculation of control uninfected fibroblasts. These studies suggest that CD8+ cell-mediated suppression and the presence of other viruses (such as CMV) could act as cofactors in influencing the extent of HIV-1 replication in vivo and, possibly, progression to disease.
Castro
B A
BA
Cancer Research Institute, University of California, San Francisco 94143-0128.
Homsy
J
J
Lennette
E
E
Murthy
K K
KK
Eichberg
J W
JW
Levy
J A
JA
D000818:Animals; D000917:Antibody Formation; D016827:CD8 Antigens / Q000276:immunology; D003586:Cytomegalovirus Infections / Q000150:complications* / Q000276:immunology; D015483:HIV Antibodies / Q000276:immunology; D015658:HIV Infections / Q000150:complications / Q000276:immunology*; D015497:HIV-1 / Q000254:growth & development* / Q000276:immunology; D008212:Lymphocyte Depletion; D002679:Pan troglodytes; D016176:T-Lymphocyte Subsets / Q000276:immunology*; D014779:Virus Replication
D016827:CD8 Antigens; D015483:HIV Antibodies