Vaccine Against Primate Immunodeficiency Retroviruses

SIV infection of rhesus macaques serves as a valuable model for HIV infection in humans. Both virusthrough the CD4 T-lymphocyte receptor and are infectious and cytopathic for CD4+ T-lymphocytes and mviruses are genetically closely related: SIV shares approximately 50 percent homology with HIV-1 andhomology with HIV-2. In SIV- infected rhesus macaques, as in HIV-infected humans, a predominantly asinfection is followed by a disease onset which is characterized by decreasing CD4+ T-lymphocytes, into opportunistic infections and increasing viral load. Due to the ability to challenge vaccinated mapathogenic virus, the SIV; rhesus macaque model system is invaluable in the development of HIV vaccimore rapid disease onset in this animal model (less than 2 years as opposed to l0 years with HIV infenables vaccine efficacy to be determined relatively quickly (for review see: Gardner and Hu, l99l).under ideal laboratory conditions, the development of a safe vaccine that will protect against SIV irigorous conditions has remained elusive. A complete vaccine would induce cytotoxic T lymphocytes (Cfour major antigenic proteins in SIV and humoral immunity against the envelope coat protein. Prelimimacaques have demonstrated that use of recombinant BCG can efficiently generate such antigen specifiproject will verify these results as well as examine the other types of immunity resulting from immuvectors. It will also validate the use of a new biological adjuvant to serve as a safe boosting agen