R.E. Kavetsky Institute of Experimental Pathology, Oncology and Radiobiology NAS of Ukraine, Kiev 03022, Ukraine
Abstract. CD150 belongs to novel CD2/CD150 subfamily of cell surface receptors. Expression of this receptor was found on activated T and B lymphocytes, monocytes and dendritic cells. CD150 was shown to play a dual role in regulation of lymphocyte fate and a potential to transmit positive or negative signals. The objective of this paper was to study CD150 expression in normal human tissues and tumors of different histogenesis using immunohistochemical approach. Our pillot tissue screening studies revealed CD150 expression outside of hematopoietic system: in basalioma and squamous cell carcinomas of uterine cervix, rectum and oral cavity. These tumors have ectodermal origin and their normal counterparts did not show expression of CD150. Detailed studies of non-Hodgkin’s lymphomas showed CD150 expression in T-cell lymphoma, mantle cell lymphoma (very low level) and in diffuse large B-cell lymphoma with activated B cell phenotype that is in accordance with CD150 expression in their normal counterparts. We also found CD150 expression in Hodgkin/Reed — Sternberg cells in Hodgkin’s lymphoma. In these lymphomas, except mantle cell lymphoma, CD150 was coexpressed with the small adaptor protein SH2D1A. Since SH2D1A is involved in regulation of CD150 signaling and function, coexpression of SH2D1A and CD150 could contribute to pathogenesis of these types of lymphomas.
