<prompt> All are B-cell marker except:CD15CD19CD21CD24  <response>: Direct lines from Wintrobes hematology..CD-15 is expressed on neutrophils, esinophils and monocytes but not on on platelets,lymphocytes and erythrocytes.About option dCD24 is expressed on B cell activation and differentiation and is lost at the plasma cell stage. It is also present ion granulocytes and thymocytes but not on mature T cells.data shows its increased levels are associated with colonbreast and pancreatic cancer. ref Robbins 7th670,9e590 