CD21 (also known as complement receptor 2 [CR2] or B2) is also associated with at least some B-cell lymphomas (Nadler et al, 1983; Scoazec et al, 1989; Gloghini & Carbone, 1993; Echeverri et al, 2002) but anti-CD21 antibody internalization has only been evaluated in a limited number of studies (Pulczynski et al, 1994; Tessier et al, 2006). This evidence concerns the gene CR2 and B-cell non-Hodgkin lymphoma.