CYTOPLASMIC LOCALIZATION OF FTS (FACTEUR THYMIQUE SERIQUE) IN THYMIC EPITHELIAL-CELLS - AN IMMUNOELECTRONMICROSCOPICAL STUDY

  • 1 January 1980
    • journal article
    • research article
    • Vol. 2  (3) , 177-186
Abstract
The localization of the facteur thymique serique (FTS) by immunoelectronmicroscopy in cultured [rat] thymic epithelial cells was attempted. The FTS antibodies labelled differently sized cytoplasmic vacuoles containing a substance of variable density. This substance occurs occasionally in crystalline structures which reacted strongly with purified FTS antibodies. On the ultrastructural level the FTS-positive cells were demonstrated to fix specifically keratin antibodies and to contain tonofilaments. Some of these cells originated from the thymic medulla, proved by the presence of microvilli-forming cytoplasmic vacuoles. The existence of FTS-positive crystalline inclusions confirmed the hypothesis of a storage process in the cytoplasm of thymic epithelial cells in vitro or in pathological conditions.