Specificity
This antibody reacts with an extracellular epitope of CD22, a 130 kDa type I transmembrane glycoprotein, of the immunoglobulin superfamily, expressed in the cytoplasm of pro-B and pre-B lymphocytes, and on the surface of mature and activated B lymphocytes. It is lost on plasma cells, peripheral blood T lymphocytes, granulocytes, and monocytes.