DatasheetSDS

S-100 protein was first extracted from the brain and at first believed to be a glial marker marker. S-100 protein is made up of two subunits, it has been identified that S-100 protein is differently expressed by various cells. This antibody shows one double peak (S-100 A and B) when tested in crossed immunoelectrophoresis against human and bovine brain extracts, and will react with S-100 protein from different species. S-100 protein beta subunit is secreted in a few tumors and all S-100 positive cells. The alpha subunit is secreted only in neurons and lymph node macrophages. The S-100 protein is a reasonably stable antigen that withstands formalin fixation and paraffin embedding. Consequently, the presence of S-100 protein is readily demonstrated in routinely processed malignant melanomas. S-100 protein expression was found in normal melanocytes, Langerhans cells, histiocytes, chondrocytes, lipocytes, skeletal and cardiac muscle, Schwann cells, epithelial and myoepithelial cells of the breast, salivary and sweat glands, in addition to glial cells. Neoplasms derived from these cells also express S-100 protein to varying degrees. A large proportion of well-differentiated tumors of salivary gland, adipose, cartilaginous tissue, and Schwann cell derived tumors express S-100 protein.