CD100 T cell expression in HIV-1–infected subjects is altered compared with healthy controls. PBMCs from early HIV-1–infected patients (n = 12), elite controllers (EC, n = 20), viremic noncontrollers (NC, n = 20), and healthy controls (HCs, n = 15) were surface stained for CD100 expression. (A) Absolute numbers of CD8⁺ T cells and CD4⁺ T cells expressing CD100. (B) Absolute CD8⁺ and CD4⁺ T cells. (C) Percentage of CD8⁺ T cells or CD4⁺ T cells expressing CD100. (D) Geometric mean fluorescence intensity (gMFI) of CD100 on CD8⁺ T cells and CD4⁺ T cells. (E-G) CD100 expression on CD8⁺ T cells from early HIV-infected subjects at time points, (i) within the first year of HIV-1 infection (early), (ii) 1 to 5 years after infection (late), and (iii) within 3 months after starting ART (treatment). (E) Absolute numbers of CD100⁺CD8⁺ T cells, (F) percentage of CD100 expression, and (G) CD100 gMFI. Statistical analysis was performed using (A-D) Kruskal Wallis tests with Dunn posttest; (E-G) paired t tests (*P < .05, **P < .01, and ***P < .001).