Premium
Loss of CD19 expression in B‐cell neoplasms
Author(s) -
Masir N,
Marafioti T,
Jones M,
Natkunam Y,
Rüdiger T,
Hansmann ML,
Mason D Y
Publication year - 2006
Publication title -
histopathology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.626
H-Index - 124
eISSN - 1365-2559
pISSN - 0309-0167
DOI - 10.1111/j.1365-2559.2005.02317.x
Subject(s) - cd19 , b cell , lymphoma , cd20 , pathology , lymphocyte , medicine , epitope , biopsy , antibody , biology , immunology
Aims : To investigate whether an antibody against an intracellular epitope can detect CD19 in routine biopsy specimens and thus to document in detail its expression in human lymphomas. Method and results : A polyclonal antibody to the C terminus of CD19 was used to immunostain paraffin‐embedded samples of normal and neoplastic lymphoid tissues. CD19 was widely expressed in normal B cells and in extramedullary plasma cells. It was found in most B‐cell neoplasms, but expression in follicular lymphoma was weak (33/69) or negative (four cases). Similarly, CD19 expression in diffuse large B‐cell lymphomas was weak (28/56) or negative (eight cases). In T‐cell‐rich B‐cell lymphomas, CD19 was also weak (4/10) or negative (three cases). CD19 was often absent in post‐transplant B lymphoproliferative disease, classical Hodgkin's disease and plasma cell neoplasms. An unexpected finding was the frequent absence of CD19 in the neoplastic cells in lymphocyte predominant Hodgkin's disease. Conclusions : CD19 can now be detected in routine biopsy specimens. In contrast to the classical pan‐B marker CD20, CD19 is not always strongly expressed in B‐cell neoplasms. Furthermore, the lymphocytic and histiocytic (L&H) cells of lymphocyte predominant Hodgkin's disease (which express most B‐cell‐associated markers) commonly lack CD19.