Association between immune activation and altered hematopoiesis. (A) Lack of correlation between CD34⁺ HPC counts and viral load in treatment-naive HIV-1–infected patients. (B) Inverse correlation between CD34⁺ HPC counts and percentages of CD38-expressing memory CD8⁺ T cells in treatment-naive HIV-1–infected patients. The Spearman rank test was used to determine correlations. Plasma levels of (C) SDF-1α, IP-10, MIG and (D) sCD14 in middle-aged (M) adults and treatment-naive HIV-1–infected patients with CD4⁺ T-cell counts > 500 (H), between 200 and 500 (I), or < 200 (L) cells/μL. The Mann-Whitney or Kruskal-Wallis tests were used for comparing 2 groups or ≥ 3 groups, respectively. *P < .05, **P < .01, and ***P < .001. Bars indicate the median.