The Cy34.1 monoclonal antibody specifically binds to the B-lymphocyte differentiation antigen CD22 on strains having the Lyb-8.2 alloantigen (e.g., A, BALB/c, CBA, C3H/He, C57BL, C57L, C58, SJL, SWR, but not AKR, DBA/1, DBA/2, NZB, PL). CD22 is expressed at high levels on mature peripheral B lymphocytes (follicular and marginal zone), B-1 cells (CD5+ B cells), and plasma cells. It is a member of the Ig gene superfamily and associates with the B-cell antigen receptor. Its sialic acid- binding immunoglobulin-like lectin (siglec) extracellular region mediates B-cell adhesion to ligands on endothelial cells in the bone marrow. Its intracellular domain is phosphorylated after cross-linking of antigen receptor or MHC class II antigen. It is involved in negative regulation of B-cell activation and protection from autoimmunity. B-cell proliferative responses to LPS or anti-mouse Ig µ chain are augmented in the presence of Cy34.1 mAb.
This antibody is routinely tested by flow cytometric analysis. Other applications were tested at BD Biosciences Pharmingen during antibody development only reported in the literature.