FIG 2.

Changes in mean percent and absolute number of peripheral blood CD4⁺ T lymphocytes and mean percent gut mucosal CD4⁺ T lymphocytes in pig-tailed macaques over time. The mean percent (A) and absolute (B) CD4⁺ T lymphocyte levels from whole blood and the mean percent CD4⁺ T lymphocytes from the gut lamina propria (C) are shown for pig-tail macaque ΔGY-infected controllers (black), ΔGY-infected progressors (blue), and SIVmac239-infected naive controls (red). (A) The percentage of CD4⁺ T lymphocytes in whole blood progressively declined in the SIVmac239 control group but remained stable for both ΔGY-controlling and -progressing animals. (B) The absolute number of CD4⁺ T lymphocytes in whole blood remained stable for the ΔGY-infected controllers, decreased in the ΔGY-infected progressors late in the course of infection, and fell rapidly in the SIVmac239-infected group. (C) The percentage of gut lamina propria CD4⁺ T lymphocytes decreased rapidly for the SIVmac239 group. For the ΔGY-infected progressors and controllers there was a mild reduction during acute infection with subsequent recovery to preinfection levels. While the ΔGY-infected controllers maintained gut lamina propria CD4⁺ T lymphocytes through chronic infection, a late decline was observed in the ΔGY-infected progressors at week 60. *, P < 0.05; **, P < 0.01 (between ΔGY-infected controller and SIVmac239 groups). P values were determined using the Mann-Whitney nonparametric test.