HIV vaccine: hopes and hurdles.

The AIDS vaccine development effort has already been facing various scientific and economic challenges. The fundamental challenge resides at the level of understanding the basic biology of HIV-1 infection and an effective antiviral immune response. There is a need to design immunogens that can elicit cross-clade neutralizing antibodies (NAbs) along with effective T-cell responses against a wide variety of primary HIV isolates. We must exploit the capabilities of the vaccine-elicited cytotoxic T cells and the NAb responses in controlling HIV-1 replication. A coordinated approach is required to understand the intricacies involved in the basic immune responses against HIV infection as well as the cross-clade effectiveness of an AIDS vaccine.