HIV type 2 primary isolates induce a lower degree of apoptosis "in vitro" compared with HIV type 1 primary isolates.
To determine whether subtypes of HIV-1 and HIV-2 vary in their ability to induce T cell apoptosis in vitro, human peripheral blood mononuclear cells (PBMC) from healthy donors and CEM.NKR-CCR5 cells were infected with a variety of HIV-1 and HIV-2 isolates in vitro. Apoptotic cell levels and chemokine and cytokine production were analyzed. Significant variations in cytopathic effects following in vitro infection with primary isolates of HIV-1 or HIV-2 subtypes were observed in PBMCs. The percent of apoptotic cells from each individual ranged from 2 to 78% after HIV-1 infection and from 0 to 28% after HIV-2 infection (p < 0.01). We did not observe significant differences in the degree of apoptosis induced among cells infected with different HIV-1 group M subtypes or group O virus, nor among cells infected with different HIV-2 isolates. However, HIV-2 induced significantly lower degree of apoptosis overall in PBMC and CEM.NKR-CC5 cells when compared with HIV-1 subtypes (p < 0.0001). No significant differences were observed in the production of chemokines, such as RANTES, MIP-1alpha, and MIP-1beta, and cytokines, such as TNF-alpha and TNF-beta when PBMC cultures were infected with different HIV-1 subtype viruses, or HIV-2 isolates. In conclusion, HIV-2 isolates induced significantly lower levels of T cell apoptosis in both PBMC and CEM.NKR-CCR5 cells than HIV-1 isolates. No differences in T cell apoptosis levels were seen between different subtypes of HIV-1 group M or group O isolates. This is consistent with the mild clinical course of infection with HIV-2 that has been reported relative to that observed with HIV-1.
Machuca
Ana
A
Laboratory of Molecular Virology, Division of Emerging and Transfusion Transmitted Diseases, Office of Blood Review and Research, Center for Biologics Evaluation and Research, Food and Drug Administration, Bethesda, Maryland 20892, USA.
Ding
Linna
L
Taffs
Rolf
R
Lee
Sherwin
S
Wood
Owen
O
Hu
Jinjie
J
Hewlett
Indira
I
D017209:Apoptosis / Q000502:physiology*; D018925:Chemokines / Q000096:biosynthesis; D016207:Cytokines / Q000096:biosynthesis; D015497:HIV-1 / Q000502:physiology*; D015498:HIV-2 / Q000502:physiology*; D006801:Humans; D066298:In Vitro Techniques; D009000:Monocytes / Q000166:cytology* / Q000378:metabolism / Q000821:virology
D018925:Chemokines; D016207:Cytokines