Attenuated-SIVmac239?nef Viral Sequencing

Different HIV/SIV vaccine vectors expressing the same viral antigens can elicit disparate T-cell responses. Within this spectrum, replicating variable vaccines like SIVmac239?nef appear to generate particularly efficacious CD8 T-cell responses. Here, we sequenced T-cell receptor ß-chain (TRB) gene rearrangements from immunodominant Mamu-A*01-restricted Tat28-35SL8-specific CD8 T-cell populations together with the corresponding viral epitope in four rhesus macaques during acute SIVmac239?nef-infection. Ultradeep pyrosequencing showed that viral variants arose with identical kinetics in SIVmac239?nef and pathogenic SIVmac239 infection. Furthermore, distinct Tat28-35SL8-specific TCR repertoires were elicited by SIVmac239?nef compared to a DNA/Ad5 prime/boost regimen, likely reflecting differences in antigen sequence stability.