Warthin-Finkeldey Polykaryocytes Demonstrate a T-Cell Immunophenotype

Warthin-Finkeldey polykaryocytes have been described in various benign and malignant lymphoid conditions since their initial identification in tonsils of patients in the prodromal stage of measles. However, the nature of these multinucleated giant cells is obscure. The authors studied the immunohistochemical profile of the Warthin-Finkeldey–type giant cells in three cases of lymphoid proliferations (two reactive, one neoplastic) containing many multinucleated cells using a panel of paraffin-reactive antibodies. Warthin-Finkeldey polykaryocytes demonstrated reactivity with Leu22 (CD43), anti-CD3, and OPD4, indicating that these cells are multinucleated T lymphocytes. The significance of these results with respect to the disorders in which these cells are found and their possible role in pathogenesis of disease are discussed.