CD22 is characterized as a doublet of 130/140 kDa and is expressed on the surface of normal human B-cells and some neoplastic B-cell lines and tumors. CD22 has also been further divided into four different epitope groups, A, B, C, and D, which represent groups of determinants situated on different portions of the CD22 molecule. Anti-CD22-SAP recognizes and specifically eliminates cells that possess the group-A epitope of the human B-cell antigen, CD22. Anti-CD22 immunotoxins have been used to study precursor-B cell acute lymphoblastic leukemia.
Anti-CD22-SAP is a chemical conjugate of a mouse monoclonal antibody to Human CD22 and the ribosome-inactivating protein, saporin. It specifically eliminates cells that express the group-A epitope of the human B-cell antigen, CD22.