Immunohistochemical Localization of Thromboxane Synthase in Normal and Neoplastic Tissues by the Monoclonal Antibody Tü 300

Abstract

Recently, Nüsing et al. (1) defined a monoclonal antibody Tue 300 (mAB Tue 300) which recognizes thromboxane synthase (T×S) in unfixed tissue sections. Studies on normal human organs revealed that this antibody labels not only thrombocytes from which the immunizing antigen was derived but also all members of the mononuclear phagocytic system, including specialized cells such as starry sky macrophages, dendritic cells of T cell areas, epithelioid cells, multinucleated giant cells, Langerhans cells and Kupffer cells. In addition, a focal labeling of epithelial cells was observed in tonsils, female breast, pancreas, salivary glands and bile ductules (2). In view of controversial findings concerning the role of thromboxane (T×A2) in tumors (for review see ref. 3), an immunohistochemical study on the cellular distribution of T×S was performed on carcinomas of breast, lung and colon.