IL-12Rβ1–deficient subjects display less memory B cells in blood. (A) Representative results of phenotypic analysis of blood B-cell subsets. (B) Frequency of naïve (IgD⁺CD27⁻), IgD⁻CD27⁺ memory, and IgD⁺CD27⁺ nonswitched memory cells within CD20⁺ B cells in control subjects (n = 61, blue) or IL-12Rβ1–deficient subjects (n = 15, orange). Unpaired Student t test. (C) Composition of blood B-cell subsets 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.