CR2 and Autoimmunity: In that study, DNB cells were found at greater frequencies in the blood of young (<60 years of age) individuals with MS relative to HC and shown to be producers of proinflammatory (tumor necrosis factor-α and lymphotoxin-α) and cytotoxic (granzyme-B) cytokines.30 Furthermore, DNB cells from individuals with MS expressed low levels of CD21, a characteristic associated with autoreactive B cells.30 Cells of a similar phenotype have been associated with autoantibody production and disease activity in other autoimmune conditions.31, 32, 33