label: Increased proportion of class-switched memory B cells
label_lc: increased proportion of class-switched memory b cells
description: "An increase in the normal proportion of class-switched memory B cells (CD19+/CD27+/IgM+/IgD+) relative to the total number of B cells. Marginal zone B cells undergo limited somatic hypermutation and produce high-affinity IgM and some IgG, whereas class-switched memory B cells synthetize IgG, IgM, and IgA."