Distinct profiles of activation marker expression on memory CD27⁻IgG⁺ B cells of CGD patients. (A) Representative and (B) comparisons of mean fluorescence intensity (MFI) profiles of expression for activation markers CD80, TACI, and CD95 were obtained from PBMCs of 9 CGD patients. Only persons with very low frequencies of CD21^lo B cells were included. Gating on CD20⁺/CD10⁻ cells established the B-cell population, and expression of IgD, IgG, and CD27 was used to establish naive (IgD⁺CD27⁻), as well as IgG⁺ CD27⁻ and CD27⁺ memory B cells. Horizontal bars represent medians.