IL-12Rβ1–deficient subjects display less CXCR5⁺ CD4⁺ T cells in blood. (A) Representative results of CXCR5 expression on blood CD4⁺ T cells. (B) Percentage of CXCR5⁺ cells within (left) total or (right) memory CD4⁺ T cells. Percentage of memory cells within total CD4⁺ T cells is shown in the center. Each dot represents a sample from either control subjects (n = 68, blue) or IL-12Rβ1–deficient subjects (n = 22, orange). Unpaired Student t test. (C) Mean fluorescent intensity of CXCR5 of CXCR5⁺ CD4⁺ T cells. (D) Percentage of CXCR5⁺ cells within (left) total and (right) memory CD4⁺ T cells at different ages. Each dot represents a sample from an individual subject. Linear regression and 95% confidence interval in each group (control or IL-12Rβ1 deficient) are indicated by solid lines and dotted lines, respectively. (E) Percentages of CXCR5⁺ cells within CD45RA⁻CD4⁺ T cells in groups of age <10. (F) CXCR5 expression in IL-12Rβ1–deficient subjects with different BCG vaccination/dissemination history. D, BCG disseminated; NV, not BCG vaccinated; R, subjects who remained asymptomatic (resistant) after BCG vaccination.