The immune response against early regulatory proteins of simian- and human immunodeficiency virus (SIV, HIV) has been associated with a milder course of infection. Here, we directly compared vaccination with Tat/Rev versus Pol/Gag. Challenge infection with SIVmac32H (pJ5) suggested that vaccination with Tat/Rev induced cellular immune responses that enabled cynomolgus macaques to more efficiently control SIV replication than the vaccine-induced immune responses against Pol/Gag. Vaccination with Tat/Rev resulted in reduced plasma SIV loads compared with control (P=0.058) or Pol/Gag-vaccinated (P=0.089) animals, with undetectable plasma viral loads in two of the four Tat/Rev-vaccinated animals. Therefore, the results warrant further investigation of the early regulatory proteins and their potential for vaccination against HIV.

Animals, Antibodies, Viral/biosynthesis/blood, Gene Products, gag/genetics/immunology, Gene Products, pol/genetics/immunology, Gene Products, rev/genetics/immunology, Gene Products, tat/genetics/immunology, Humans, Immunity, Cellular, Macaca fascicularis, RNA, Viral/blood/genetics, SAIDS Vaccines/genetics/*immunology, Simian Acquired Immunodeficiency Syndrome/immunology/prevention & control/virology, Simian immunodeficiency virus/genetics/*immunology, Viremia/immunology/prevention & control/virology,
Erasmus MC: University Medical Center Rotterdam

Stittelaar, K.J, Gruters, R.A, Schutten, M, van Baalen, C.A, van Amerongen, G, Cranage, M.P, … Osterhaus, A.D.M.E. (2002). Comparison of the efficacy of early versus late viral proteins in vaccination against SIV. Vaccine, 20(23-24), 2921–2927. doi:10.1016/S0264-410X(02)00219-0