FIG. 1.

Differential expression of CD14 and CD16 on the surface of peripheral blood monocytes in Rhesus macaques, sooty mangabeys, and humans. Representative flow cytometric analysis of CD14⁺CD16⁺ monocyte in one healthy volunteer and an HIV-infected individual (A). Mean percentage of CD14⁺⁺CD16⁺ and CD14⁺CD16⁺⁺ in uninfected and HIV-infected individuals (C). Flow cytometric density plots characteristic for healthy and SIV_mac251-infected Rhesus macaques and sooty mangabeys (B). Three distinct monocyte subsets were delineated by lines that were drawn based on fluorescence-minus-one (FMO) controls: classical CD14⁺⁺CD16⁻, I—intermediate CD14⁺⁺CD16⁺, and NC—nonclassical CD14⁺CD16⁺⁺. Mean frequency of CD14⁺⁺CD16⁺ and CD14⁺CD16⁺⁺ monocyte subsets in healthy and SIV_mac251-infected Rhesus macaques (D) and SIV_SM-infected and uninfected sooty mangabeys (E). Plots represent means while whiskers represent standard deviation (SD). Statistically significant differences between groups are indicated. Mean fluorescence intensity (MFI) of CCR5 expression in different monocyte subsets in Rhesus macaques (RM) (F), uninfected sooty mangabeys, and SIV_SM-infected sooty mangabeys (SM) (G). Plots represent means while whiskers represent standard deviation. Statistically significant differences between groups are indicated. The paired t-test was used in the statistical analysis in B, C, D, E, and G.