Figure 2. Quantification of Env-specific humoral responses in rectal and vaginal mucosa of rhesus macaques in response to immunization.

(A) Env-specific IgG and (B) IgA levels in vaginal washes collected 3 weeks after each immunization. (C) Comparison of vaginal Env-specific IgG and IgA levels at wk41, the last time point prior to SIV challenge. (D) Env-specific IgG and (E) IgA levels in rectal secretions collected 3 weeks after each immunization. (F) Comparison of rectal Env-specific IgG and IgA levels at wk41. Vaginal and rectal secretions that tested positive for blood were excluded from the analysis. Panels A-C: Pre-vaccination n=28; 1^st Adeno n=33; 2^nd Adeno n =35; 1^st boost n=37; 2^nd boost n=36. Panels D-F: Pre-vaccination n=25; 1^st Adeno n=23; 2^nd Adeno n=24; 1^st boost n=30; 2^nd boost n= 28. Dynamics of Env-specific antibody secreting cells (ASC: PBs and PCs) assessed by ELISpot for (G) IgG secreting cells and (H) IgA secreting cells. (I). Eighteen immunized animals were selected for analysis of rectal Env-specific IgA and IgG ASC. All 18 samples were included in rectal IgA Env-specific ASC ELISpot assays for all timepoints. Some samples did not have sufficient cells for the IgG Env-specific ASC ELISpot as follows: Panel G: Pre-vaccination n=14; 1^st Adeno n=18; 2^nd Adeno n=14, 1^st boost n=15; 2^nd boost n=18. (I) Comparison of vaccinated and control animals for IgG and IgA Env-specific ASC at wk41. Data were analyzed by the Wilcoxon Signed-rank Test; Comparisons between vaccinated and control groups in (C), (F) and (I) were analyzed by the Mann-Whitney U test. Horizontal and vertical bars denote mean and SEM. *p < 0.05; **p<0.01; ***p<0.001; ****p<0.0001.