A p50 surface antigen restricted to human urinary bladder carcinomas and B lymphocytes

Cancer Immunol Immunother. 1985;20(1):23-8. doi: 10.1007/BF00199769.


We have previously described the derivation of a monoclonal antibody, S2C6, to a novel 50 Kdalton antigen associated with human urinary bladder carcinoma. No reactions were obtained with carcinomas of unrelated origin or with normal urothelial cells. However, the antibody also reacted with a similar antigen on some cell lines of B lymphocyte origin. Using large panels of target cells we have now shown that this reactivity was entirely restricted to cells of the B lineage within the haematopoietic system. As opposed to its apparent restriction to malignant cells of the urothelium, the S2C6 antigen was expressed by normal B lymphocytes as well as by many malignant B cells (chronic lymphocytic leukaemia, hairy cell leukaemia and immunocytoma). Pre-B cells derived from acute lymphocytic leukaemia and plasma cells from multiple myeloma lacked the antigen. Expression was significantly enhanced on cultured B cells from Burkitt lymphomas and on Epstein-Barr virus-transformed lymphoblastoid cell lines including those of the pre-B phenotype derived from fetal bone marrow. As judged from the molecular size and the distribution pattern displayed by the S2C6 antigen it appears to be distinct from other B cell antigens previously described. A possible relation of the S2C6 antigen to a receptor for B cell growth factors is discussed.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antibodies, Monoclonal
  • Antigens, Neoplasm / analysis*
  • Antigens, Surface / analysis*
  • B-Lymphocytes / immunology*
  • Blood Cells / immunology
  • Carcinoma / immunology*
  • Cell Transformation, Viral
  • Herpesvirus 4, Human
  • Humans
  • Palatine Tonsil / immunology
  • Spleen / immunology
  • Thymus Gland / immunology
  • Urinary Bladder Neoplasms / immunology*


  • Antibodies, Monoclonal
  • Antigens, Neoplasm
  • Antigens, Surface