Human natural killer cells in asymptomatic human immunodeficiency virus-1 Infection

Objectives: We evaluated whether DNA immunization with HIV-1 regulatory genes change natural killer (NK) effector cell activity. NK cells are the most important cells for the immediate host defense against virus-infected and tumor cells. We analyzed the NK activities of HIV-1-infected individuals against K562 cells (the classical assay) as well as against a CD4+ cell line with and without HIV-7 infection. CD4+ T lymphocytes are the main target cells for HIV-7 infection in vivo. Various proportions of the CD4+ T lymphocyte population carry the HIV-1 genome, produce virus and contribute to the systemic spread of HIV-1. Methods: CD4+ cell lines were established through HTLV-1 transformation which made the cells susceptible to NK lysis, NK activity was then tested in a Cr-51 release assay. Results: NK cells of asymptomatic HIV-infected individuals mediated considerable lytic activity against K562 cells as well as against the uninfected and HIV-1-infected CD4+ cell line, and so did the NK cells of HIV-1-infected patients on highly active antiretroviral treatment. Conclusion: DNA immunization with HIV-7-regulatory genes did not significantly change the NK effector cell activity. Copyright (C) 2001 S. Karger AG, Basel.