TY - JOUR
T1 - Expression of two markers of germinal center T cells (SAP and PD-1) in angioimmunoblastic T-cell lymphoma
AU - Roncador, Giovanna
AU - Verdes-Montenegro, José Francisco García
AU - Tedoldi, Sara
AU - Paterson, Jennifer C.
AU - Klapper, Wolfram
AU - Ballabio, Erica
AU - Maestre, Lorena
AU - Pileri, Stefano
AU - Hansmann, Martin Leo
AU - Piris, Miguel A.
AU - Mason, David Y.
AU - Marafioti, Teresa
PY - 2007/8
Y1 - 2007/8
N2 - Background and Objectives: In the present paper we report that SAP, an intracytoplasmic molecule that is involved in cell signaling, is an immunohistologic marker for germinal center T cells in paraffin-embedded tissue. We document its expression, and also that of PD-1 (another recently described marker of germinal center T cells to which a new antibody has been raised), in normal and neoplastic lymphoid tissue to evaluate the suggestion that helper T cells within the germinal centers of human lymphoid tissue are the cell of origin of angioimmunoblastic T-cell lymphoma (AITL), and to assess the diagnostic value of these two markers. Design and Methods: Expression of SAP and PD-1 was investigated by immunohistochemistry in paraffin-embedded tissue sections and in cell lines. Western blotting was performed on cell lines, and antibody specificity was confirmed by immunostaining of transfected cells. Results: Screening on more than 500 lymphoma biopsies showed that 95% (40/42) of cases of AITL expressed at least one of these markers. SAP was also expressed on many cases (15/21) of acute T lymphoblastic leukemia, in keeping with its presence in cortical thymocytes. However, PD-1 and SAP were also found in a minority of cases of peripheral T-cell lymphoma other than AITL, in contrast to a report that the former marker is specific for AITL. This observation raises the possibility that such non-angioimmunoblastic cases may be related to germinal center helper T cells. Interpretation and Conclusions: These two markers provide additional evidence that AITL arises from germinal center T cells. They may also prove of value in the diagnosis of this disease since a negative reaction was rarely observed in this disorder.
AB - Background and Objectives: In the present paper we report that SAP, an intracytoplasmic molecule that is involved in cell signaling, is an immunohistologic marker for germinal center T cells in paraffin-embedded tissue. We document its expression, and also that of PD-1 (another recently described marker of germinal center T cells to which a new antibody has been raised), in normal and neoplastic lymphoid tissue to evaluate the suggestion that helper T cells within the germinal centers of human lymphoid tissue are the cell of origin of angioimmunoblastic T-cell lymphoma (AITL), and to assess the diagnostic value of these two markers. Design and Methods: Expression of SAP and PD-1 was investigated by immunohistochemistry in paraffin-embedded tissue sections and in cell lines. Western blotting was performed on cell lines, and antibody specificity was confirmed by immunostaining of transfected cells. Results: Screening on more than 500 lymphoma biopsies showed that 95% (40/42) of cases of AITL expressed at least one of these markers. SAP was also expressed on many cases (15/21) of acute T lymphoblastic leukemia, in keeping with its presence in cortical thymocytes. However, PD-1 and SAP were also found in a minority of cases of peripheral T-cell lymphoma other than AITL, in contrast to a report that the former marker is specific for AITL. This observation raises the possibility that such non-angioimmunoblastic cases may be related to germinal center helper T cells. Interpretation and Conclusions: These two markers provide additional evidence that AITL arises from germinal center T cells. They may also prove of value in the diagnosis of this disease since a negative reaction was rarely observed in this disorder.
KW - AITL
KW - Germinal center T cells
KW - Immunohistochemistry
KW - Lymphoma
KW - Western blotting
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U2 - 10.3324/haematol.10864
DO - 10.3324/haematol.10864
M3 - Article
C2 - 17640856
AN - SCOPUS:35748959075
VL - 92
SP - 1059
EP - 1066
JO - Haematologica
JF - Haematologica
SN - 0390-6078
IS - 8
ER -