Objectives: We evaluated whether DNA immunization with HIV-1 regulatory gen
es 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 ag
ainst 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 ce
lls for HIV-7 infection in vivo. Various proportions of the CD4+ T lymphocy
te population carry the HIV-1 genome, produce virus and contribute to the s
ystemic spread of HIV-1. Methods: CD4+ cell lines were established through
HTLV-1 transformation which made the cells susceptible to NK lysis, NK acti
vity was then tested in a Cr-51 release assay. Results: NK cells of asympto
matic 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 a
ntiretroviral treatment. Conclusion: DNA immunization with HIV-7-regulatory
genes did not significantly change the NK effector cell activity. Copyrigh
t (C) 2001 S. Karger AG, Basel.