Affiliation:
1. MRC Laboratories, Fajara, Banjul, The Gambia
Abstract
ABSTRACT
Natural killer (NK) cells are potent effectors of natural immunity and their activity prevents human immunodeficiency virus type 1 (HIV-1) viral entry and viral replication. We sought to determine whether NK immune responses are associated with different clinical course of HIV-1 and HIV-2 infections. A cross-sectional analysis of NK cell responses was undertaken in 30 HIV-1 and 30 HIV-2 subjects in each of three categories of CD4
+
-T-cell counts (>500, 200 to 500, and <200 cells/μl) and in 50 HIV-uninfected control subjects. Lytic activity and gamma interferon (IFN-γ) secretion were measured by chromium release and enzyme-linked immunospot assays, respectively. Flow cytometry was used to assess intracellular cytokines and chemokines. Levels of NK cytotoxicity were significantly higher in HIV-2 than in HIV-1 infections in subjects with high CD4
+
-T-cell counts and were similar to that of the healthy controls. In these HIV-2 subjects, cytolytic activity was positively correlated to NK cell count and inversely related to plasma viremia. Levels of intracellular MIP-1β, RANTES, tumor necrosis factor alpha, and IFN-γ produced by NK CD56
bright
cells were significantly higher in HIV-2- than HIV-1-infected subjects with high CD4
+
-T-cell counts but fell to similar levels as CD4 counts dropped. The data suggest efficient cytolytic and chemokine-suppressive activity of NK cells early in HIV-2 infection, which is associated with high CD4
+
T-cell counts. Enhancement of these functions may be important in immune-based therapy to control HIV disease.
Publisher
American Society for Microbiology
Subject
Virology,Insect Science,Immunology,Microbiology
Reference38 articles.
1. Ahmad, A., and J. Menezes. 1995. Positive correlation between the natural killer and gp 120/41-specific antibody-dependent cellular cytotoxic effector functions in HIV-infected individuals. J. Acquir. Immune Defic. Syndr. Hum. Retroviruses10:115-119.
2. Ahmad, R., S. T. Sindhu, E. Toma, R. Morisset, J. Vincelette, J. Menezes, and A. Ahmad. 2001. Evidence for a correlation between antibody-dependent cellular cytotoxicity-mediating anti-HIV-1 antibodies and prognostic predictors of HIV infection. J. Clin. Immunol.21:227-233.
3. Berry, N., K. Ariyoshi, S. Jaffar, S. Sabally, T. Corrah, R. Tedder, and H. Whittle. 1998. Low peripheral blood viral HIV-2 RNA in individuals with high CD4 percentage differentiates HIV-2 from HIV-1 infection. J. Hum. Virol.1:457-468.
4. Biron, C. A., K. B. Nguyen, G. C. Pien, L. P. Cousens, and T. P. Salazar-Mather. 1999. Natural killer cells in antiviral defense: function and regulation by innate cytokines. Annu. Rev. Immunol.17:189-220.
5. Bonaparte, M. I., and E. Barker. 2003. Inability of natural killer cells to destroy autologous HIV-infected T lymphocytes. AIDS17:487-494.
Cited by
31 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献