gp100 (Melanosome, 95kD melanocyte-specific secreted glycoprotein, M-beta, Melanocyte lineage specific antigen GP100, Melanocyte protein Pmel 17, Melanoma associated ME20 antigen, Melanosomal matrix protein17, p100, p26, PMEL17, Premelanosome protein, Secreted melanoma-associated ME20 antigen, SILV, Silver homolog) (PE)

By immunohistochemistry, it specifically recognizes a protein in melanocytes and melanomas. This MAb reacts with junctional and blue nevus cells and variably with fetal and neonatal melanocytes. Intradermal nevi, normal adult melanocytes, and non-melanocytic cells are negative. It does not stain tumor cells of epithelial, lymphoid, glial, or mesenchymal origin. Metastatic amelanotic melanoma can often be confused with a variety of poorly differentiated carcinomas, large cell lymphomas, and sarcomas using H & E stains alone. It is also difficult to differentiate melanoma from spindle cell carcinomas...