Multiple studies on human immunodeficiency virus and simian immunodeficiency virus (SIV) infection have indicated the association of major histocompatibility complex class I (MHC-I) genotypes with rapid or slow AIDS progression.
We then discovered that vaccinated Chinese macaques developed a previously unrecognized class of non-cytolytic MHC-Ib/E-restricted CD8<sup>+</sup> T cells (or CD8<sup>+</sup> T-Regs) that suppressed the activation of SIV RNA-infected CD4<sup>+</sup> T cells and thereby inhibited the (activation-dependent) reverse transcription of the virus and prevented the establishment of SIV infection.
In human immunodeficiency virus (HIV) and simian immunodeficiency virus (SIV) infections, host major histocompatibility complex class I (MHC-I) genotypes have a great impact on viral replication and MHC-I-associated viral genome mutations are selected under CD8<sup>+</sup> T-cell pressure.