Before vaccine candidates are tested in humans, they must be first be evaluated in the laboratory for safety and efficacy. Studies in animal models have been vital in determining disease mechanisms, predicting disease triggers, and developing treatments and diagnostic tests. It has been difficult to study HIV because the virus exclusively infects and causes disease in humans. As a result, there is no ideal animal model that can imitate the natural history and pathogenesis of HIV/AIDS in the human body.
Scientists are using macaque monkeys infected with simian immunodeficiency virus (SIV), a virus closely related to HIV, as an approximate animal model. This model is useful because SIV in macaques follows a disease course that is similar to HIV. Macaques are used to evaluate vaccines that closely resemble the ones being developed for humans. This provides some clues to the safety and potential efficacy of a vaccine candidate. In addition to nonhuman primates, researchers are making progress in developing mouse models that may be used in the future for evaluating HIV vaccine candidates.
Data from animal models provides useful information (e.g. safety, potential efficacy) that can help guide scientists on whether the vaccine candidate should be moved into human clinical trials.
Two grant awards were made through the Consortia for AIDS Vaccine Research in Nonhuman Primates in 2011 to increase our understanding of the nonhuman primate models. Through this program, Emory University in Atlanta and Beth Israel Deaconess Medical Center, part of Harvard University in Boston, will co-lead research designed to understand the events that occur at the earliest stages of mucosal SIV infection and how those events can be blocked or mediated by vaccine-induced immune responses.
Through a contract mechanism, NIAID supports Simian Vaccine Evaluation Units (SVEUs) to serve as a resource to evaluate promising SIV and HIV vaccines in nonhuman primates in support of HIV vaccine development. NIAID accepts proposals from investigators for vaccine studies that if approved, are conducted at one of the SVEU sites.
Last Updated July 27, 2012
Last Reviewed July 27, 2012