MOLECULAR CHARACTERIZATION OF HUMAN MONOCLONAL-ANTIBODIES SPECIFIC FOR SEVERAL HIV PROTEINS - ANALYSIS OF THE V(H)3 FAMILY EXPRESSION

We have analyzed the heavy-chain variable (V-H) region genes expressed by a panel of human monoclonal antibodies derived from an immunized v olunteer, an AIDS patient and seropositive asymptomatic donors, and sp ecific for HIV-1 enu, pol and gag gene products. The third complementa rity-determining regions show a high complexity with unconventional ge ne recombination events. Most of the V-H genes utilized are also frequ ently encountered in other immune responses. Their sequences are, in g eneral, typical of an antigen-driven immune response. Molecular mechan isms that generate high-affinity antibodies are then effective during HIV infection. Remarkably, V(H)3 family, which dominates the human ant ibody repertoire, is barely encountered among anti-HIV antibodies.