Human immunodeficiency virus vaccine an update

Since the discovery of acquired immuno deficiency syndrome (AIDS) in late1980s, the spread of human immunodeficiency virus (HIV) has reached pandemic proportions, representing a global developmental and public health threat. Finding of a safe, globally effective and affordable HIV vaccine offers the best hope for the future control of the disease pandemic. Significant progress has been made over the past years in the areas of basic virology, immunology, and pathogenesis of HIV/AIDS and the development of anti-retroviral drugs. However, the search for an HIV vaccine faces formidable scientific challenges related to the high genetic variability of the virus, the lack of immune correlates of protection, limitations with the existing animal models and logistical problems associated with the conduct of multiple clinical trials. Most of the vaccine approaches developed so far aim at inducing cell-mediated immune responses. Multiple vaccine concepts and vaccination strategies have been tested, including DNA vaccines, subunit vaccines, live vectored recombinant vaccines, various prime-boost vaccine combinations and vaccine based on broadly neutralizing human anti-HIV Antibody 2G12. This article reviews the state of the art in HIV vaccine research, summarizes the results obtained so far and discusses the challenges to be met in the development of a successful HIV vaccine.