Postembedding immunogold electron microscopy for S100, tubulin, and cytoskeletal proteins in an amelanotic malignant melanoma
Hearn, S.A.; Kontozoglou, T.E.
Modern Pathology An Official Journal of the United States and Canadian Academy of Pathology Inc 2(1): 46-54
1989
ISSN/ISBN: 0893-3952 PMID: 2922390 Document Number: 334062
A postembedding Protein A-colloidal gold technique was used for the ultrastructural immunocytochemical investigation of S100, tubulin, and cytoskeletal proteins in a Lowicryl K4M-embedded melanoma with numerous microtubules. S100 protein was localized in the cytoplasm and the nuclei of tumor cells. Melanosomes were not labeled with S100. Perinuclear intermediate filaments and filaments in cytoplasmic processes reacted positively for vimentin. The straight, rod-shaped, parallel intracisternal microtubules failed to react with antisera to tubulin, S100, vimentin, cytokeratin, neurofilaments, desmin, glial fibrillary acidic protein, and immunoglobulin light chains. These results give an improved correlation between the ultrastructural and immunocytochemical characteristics of the tumor, confirm the melanocytic origin of it, and demonstrate the application and usefulness of the postembedding immunogold method in the investigation of the protein composition of subcellular structures.