Linker for activation of T cells (LAT), a novel immunohistochemical marker for T cells, NK cells, mast cells, and megakaryocytes: evaluation in normal and pathological conditions.

Journal Article (Journal Article)

LAT (linker for activation of T cells) is an integral membrane protein of 36-38 kd that plays an important role in T cell activation. Using a rabbit polyclonal antibody generated against the cytosolic portion of LAT, we investigated the immunohistochemical expression of LAT in normal and pathological hematolymphoid tissues. LAT reacts with human T cells in paraffin sections, including decalcified bone marrow trephines. LAT appears early in T cells at the thymocyte stage and before TdT expression in embryos, and is expressed in peripheral lymphoid tissues, without restriction to any T cell subpopulations. In addition to T cells, natural killer (NK) cells (evaluated with flow cytometry), megakaryocytes and mast cells are also LAT-positive, whereas B cells and other myeloid and monocytic derived cells are negative. Tested on a total of 264 paraffin-embedded tissue biopsies, LAT reacted with the great majority (96.8%) of T/NK-cell neoplasms, covering the full range of T cell maturation. Although antibodies to both LAT and CD3 had a similarly high sensitivity in the staining of T/NK-cell lymphomas, when used in conjunction, they successfully identified a higher number of cases (98.4%). Atypical megakaryocytes from different hematological disorders, as well as mast cells in mastocytosis were also LAT-positive, but all neoplasms of B cell origin, Hodgkin's lymphomas, and several nonlymphoid malignancies were negative. These data indicate that the anti-LAT antibody may be of value to diagnostic histopathologists for the identification of T cell neoplasms.

Full Text

Duke Authors

Cited Authors

  • Facchetti, F; Chan, JK; Zhang, W; Tironi, A; Chilosi, M; Parolini, S; Notarangelo, LD; Samelson, LE

Published Date

  • April 1999

Published In

Volume / Issue

  • 154 / 4

Start / End Page

  • 1037 - 1046

PubMed ID

  • 10233842

Pubmed Central ID

  • PMC1866564

International Standard Serial Number (ISSN)

  • 0002-9440

Digital Object Identifier (DOI)

  • 10.1016/S0002-9440(10)65356-4


  • eng

Conference Location

  • United States