Switched Memory B cells are indicators of normal B cell activation and development in germinal centers of lymph nodes or other secondary lymphoid organs. The amount of switched memory B cells in peripheral blood is an indicator for humoral immunodeficiency, such as specific antibody deficiency (SAD) or common variable immunodeficiency (CVID).

Non-target cells are labeled with a cocktail of biotinylated CD2, CD14, CD16, CD36, CD43, CD235a (glycophorin A), Anti-IgM, and Anti-IgD antibodies. These cells are subsequently magnetically labeled with Anti-Biotin MicroBeads. Highly pure switched memory B cells are obtained by depletion of the magnetically labeled cells.

Purified switched memory B cells can be used for studies in cell biology or molecular biology and functional assays.