Figure 2.

Relationship between helper CD4⁺ T‐cell count and regulatory T (Treg) cells. HIV‐infected participants were grouped into three categories according to their helper CD4⁺ T‐cell counts [CD4 < 350 cells/mm³ (n = 5); 350–499 cells/mm³ (n = 9); >500 cells/mm³ (n = 17)]. When compared with uninfected participants (n = 17), the median number of Treg cells diminished proportionately with the helper CD4⁺ T‐cell count (a). The lowest values were observed in HIV‐infected participants with CD4 < 350 cells/mm³ (P < 0·05). However, this group showed significant increase in Treg cell percentages within total CD4⁺ T cells compared with other groups (b) with helper CD4⁺ T‐cell count between 350 and 499 cells/mm³ (P < 0·05) or > 500 cells/mm³ (P < 0·001). (c, d) Helper CD4⁺ T‐cell count of HIV‐infected participants correlated positively with the total number of Treg cells and negatively with the percentages of Treg cells. Bars represent the median values, which were compared using Kruskal–Wallis test followed by Dunn's multiple comparison test. (*P <0·05; **P <0·001) Each dot represents a single individual and the correlation was calculated using Spearman test.