Thymic hormone‐containing cells. VI. Immunohistologic evidence for the simultaneous presence of thymulin, thymopoietin and thymosin α1 in normal and pathological human thymuses

Abstract

The localization of the three best-defined thymic hormones, namely, thymulin, thymopoietin and thymosin α1 was studied by immunofluorescence using antibodies directed against these three molecules. With both human thymus frozen sections and cultured cells, thymic hormones were found exclusively in the epithelial component (recognized by its keratin content), in normal as well as pathological thymuses. The double-labeling experiments using the different anti-thymic hormone antibodies showed that the same epithelial cells contained the three hormones. These results suggest that the production of different hormones in the thymus is accomplished by the same epithelial cells.