EMB and infection: SIV infection was, however, associated with a significant increase in SIVmac239-CS.23 gp70 V1V2 specific antibody responses at 2 weeks PI in both control and vaccinated animals with the responses being significantly higher in vaccinated animals after infection as compared to the control animals suggesting that tonsil vaccination likely primed tier 2 SIVmac239-CS.23 non-neutralizing V1V2 antibody responses prior to infection albeit at low levels that were boosted anamnestically after infection.