PAX-5

Formalin-fixed, paraffin embedded tissue block or cell block, or 1 unstained charged slide for each test requested plus 3-4 additional unstained slides cut at 4 microns. Adequate space on each slide for control tissue is required.

PAX-5 is expressed in all stages of B-cell development as early as pro-B-cells and it is down regulated (silenced) in plasma cell stage. It is a sensitive and specific pan-B-cell marker and it is expressed in the great majority of mature and immature B-cell neoplasms and nodular lymphocyte predominant Hodgkin lymphoma. It is also expressed at a low intensity in classical Hodgkin lymphoma.