Immunohistochemical demonstration of cytokeratins in endocrine cells of the human pituitary gland and in pituitary adenomas.
Ten non-neoplastic pituitary glands and 22 pituitary adenomas producing different hormones were studied by immunofluorescence microscopy as well as peroxidase-antiperoxidase and biotin-avidin techniques on frozen sections and formalin-fixed, paraffin-embedded material using antibodies to cytokeratin, vimentin, GFAP, neurofilament protein and different pituitary hormones. The endocrine cells in non-neoplastic pituitary glands as well as in most pituitary adenomas were cytokeratin-positive. The cytoplasmic cytokeratin distribution patterns of non-neoplastic and tumor cells were similar and typical of the type of hormone produced: GH-producing normal cells showed a paranuclear condensation of cytokeratin-reactive intermediate filaments; this accumulation was even further accentuated in GH-producing adenomas resulting in fibrous bodies (Kovacs and Horvath 1978) decorated by cytokeratin antibodies. Prolactin-producing cells showed a less intense cytoplasmic cytokeratin-specific staining with focal paranuclear accentuation in non-neoplastic as well as in neoplastic glands. ACTH-producing cells in normal pituitary glands as well as in adenomas exhibited a strong and more uniform cytoplasmic cytokeratin staining. The cytokeratin reactivity in glycoprotein hormone-producing cells of non-neoplastic tissue and adenomas was weak. Vimentin and GFAP reactivity was confined to agranular folliculo-stellate cells. The specific and different distribution patterns of cytokeratins in pituitary cells can, therefore, provide an (indirect) indication to the production of a specific hormone if immunocytochemistry fails to demonstrate hormone production.
D000236:Adenoma / Q000378:metabolism*; D005260:Female; D006651:Histocytochemistry; D006801:Humans; D007120:Immunochemistry; D007381:Intermediate Filament Proteins / Q000378:metabolism; D007633:Keratins / Q000378:metabolism*; D008297:Male; D008856:Microscopy, Fluorescence; D010902:Pituitary Gland / Q000166:cytology / Q000378:metabolism*; D010911:Pituitary Neoplasms / Q000378:metabolism*; D014018:Tissue Distribution
D007381:Intermediate Filament Proteins; D007633:Keratins