ITGAX and systemic lupus erythematosus: In SLE, CD11c+ B cells are candidate target B cells for Tph cells; CD11c+ B cells, also known as double negative 2 (DN2) B cells or age-associated B cells (ABCs), do not express IgD, CD27, or CXCR5 and are supposed to differentiate extrafollicularly (50) (Fig. 1, right).