Figure 1. Viral Target cells in the rectal IEL correlated with SHIV acquisition.

a). Viral acquisition curves from two naïve cohorts (N7 and N11) were demonstrated in a low-dose repeated intrarectal challenge model with weekly challenge of SHIVS_F162P4 virus. b–f). Multi-color flow cytometry techniques were used to measure and compare the frequencies of rectal LP CD25⁺FOXP3⁺ of CD4⁺T cells (b), rectal LP CD14+MDSCs (c) and CD15+MDSCs (d) cells; as well as the viral target cells (Ki67⁺CCR5⁺ in CD4⁺T cells) in PBMC (e) and rectal IEL (f) in N7 and N11 cohorts. Mann-Whitney tests were used for comparisons. g–h) Correlations between viral target cells in PBMC (g) and rectal IEL(H) and number of viral exposures for the animals to get infected were performed using Spearman’s tests. Mean±SEM are shown. Triangles denote the N7 group, and filled circles denote the N11 group.