HIV-gp160 modulates differentially the production in vitro of IgG, IgA and cytokines by blood and tonsil B lymphocytes from HIV-negative individuals.

HIV1-gp160 holds promises in anti-HIV vaccinal strategies. However, this molecule has been described to exhibit superantigenic activities. The present study aimed at examining the effect(s) of HIV1-gp160 on human B cells and in particular on B cells originating from HIV- donors. We purified human B cells of various origins, i.e. from blood and from tonsils (representing a mucosal-type origin), and we tested these cells (stimulated with a polyclonal B cell activator, interleukin (IL)-2 and IL-10 as cytokines, and recombinant HIV1-gp160) for the production of IgG and IgA in an in vitro model. Gp160 induced significantly less total IgG by blood - but not tonsil-originating - B cells and did not affect total IgA production. Further, HIV1-gp160 up-regulated IL-2-, IL-4- and IL-10-mRNA levels in stimulated blood B cells (these cytokines are known to be active on B cell activation and differentiation). Interestingly, HIV1-gp160 also up-regulated IL-1beta-, transforming growth factor (TGF)-beta-, interferon (IFN)-gamma- and IL-12-mRNA levels in stimulated mucosal-type, tonsil-originating, B cells. As these latter cytokines are involved in proinflammatory activities, HIV-gp160 delivery at the mucosal sites would be compatible with an adjuvant activity.