Multiple HLA-class I-specific inhibitory NK receptor expression and IL-4/IL-5 production by CD8+T-cell clones in HIV-1 infection

Several mechanisms may contribute to the decline in HIV-1 specific CDS + cy totoxic T-lymphocyte (CTL) activity that is observed in infected patients, including loss of CD4 + cell help, antigenic shift, impaired clonogenicity and functional impairment due to expression of inhibitory NK receptors (iNK Rs). In addition to a decrease in HIV-l-specific cytolytic activity, an inc reased proportion of CD8 + T-cells producing IL-4 and IL-5 has been recentl y observed in advanced HIV-I infection. Remarkably, an impaired HIV-1-speci fic CTL activity was primarily detected among the TC0/Tc2 CD8 + CTLs. A ser ies of CD3 + CD8 + T-cell clones expressing inhibitory NK receptors (iNKRs) isolated from HIV-I infected patients was analyzed in order to determine t heir cytokine production pattern and to assess the extent of iNKR expressio n at the single cell level. Our data indicate that iNKR + CD3 + CD8 + clone s isolated from infected patients frequently express multiple iNKR and may produce IL-4 and IL-5 to a relevant extent. (C) 2000 Elsevier Science B.V. All rights reserved.