Epitope-specific CD8 T cell kinetics rather than viral variability determine the timing of immune escape in simian immunodeficiency virus infection

Abstract

CD8+ T cells are important for the control of chronic HIV infection. However, the virus rapidly acquires "escape mutations" that reduce CD8+ T cell recognition and viral control. The timing of when immune escape occurs at a given epitope varies widely among patients and also among different epitopes within a patient. The strength of the CD8+ T cell response, as well as mutation rates, patterns of particular amino acids undergoing escape, and growth rates of escape mutants, may affect when escape occurs. In this study, we analyze the epitope-specific CD8+ T cells in 25 SIV-infected pigtail macaques responding to three SIV epitopes. Two epitopes showed a variable escape pattern and one had a h..