The E11 monoclonal antibody specifically binds to CD35. CD35 is also known as Complement receptor type 1 (CR1), C3b/C4b receptor, C3BR, C4BR, Immune adherence receptor, or KN. CD35 is a type I transmembrane glycoprotein that exists in four allelic forms of 160, 190, 220 and 250 kDa. CD35 serves as a receptor for complement fragments C3b, iC3b, C3dg, C4b, iC3, and iC4. It enhances phagocytosis by neutrophils and monocytes and regulates complement activation. It is expressed on erythrocytes, granulocytes, monocytes, B cells, and some dendritic cells, T cells, and NK cells. It binds complement components C3b and C4b, mediating. This antibody cannot inhibit the phagocytic capacity of granulocytes. The CD35 antibody is useful in studies of cells that express complement receptors.