Last revised by Daniel J Bell on 16 Feb 2024

S100 is a family of cytoplasmic calcium-binding proteins expressed in numerous cell lines which can be targeted by immunohistochemistry. Staining for S100 is helpful in characterizing a number of tumors, including malignant melanoma, glial tumors, neurogenic tumors (e.g. schwannomas and neurofibromas), mesenchymal tumors (e.g. chondromas, chondrosarcomas, liposarcomas, some osteogenic sarcomas) and some histiocytic tumors 1,2

History and etymology

S100 is a contracture of "100% soluble" in ammonium sulfate at neutral pH 3.

ADVERTISEMENT: Supporters see fewer/no ads

Updating… Please wait.

 Unable to process the form. Check for errors and try again.

 Thank you for updating your details.