Report of the cent gardes HIV vaccine conference the B-cell response to HIV. Part 1: Broadly neutralizing antibodies fondation mérieux conference center, Veyrier du Lac, France, 5-7 November 2012

The Cent Gardes Conference on HIV Vaccines took place on November 5-7, 2012 at the Fondation Mérieux Conference Center, Annecy, France. The aim of the meeting was to review the B cell response to human immunodeficiency virus-1 (HIV-1) infection and immunization, from broadly neutralizing antibodies (bnAbs) to non-neutralizing antibodies (n-nAbs). The production of cross-reactive bnAbs is one of the greatest challenges in HIV-1 vaccine development. In natural HIV infection, bnAbs are observed in only a minority of infected individuals and take a few years to develop. This report presents a comprehensive review of how these Abs arise, the possible role of viral evolution, and the activation and maturation requirements of B cell lines that lead to their production. Passive immunization with bnAbs provides efficient, cross-clade protection against simian/human immunodeficiency chimeric virus (SHIV) challenges in nonhuman primates. Despite many efforts to design immunogens that elicit them by active immunization, no immunogen other than HIV itself has yet been able to elicit a bnAb response. For this reason, innovative approaches are under investigation, including their production in the body through a gene delivery approach, vector immunoprophylaxis.