Nacolomab Tafenatox

**Semantic type:** Immunologic Factor|Pharmacologic Substance

**Definition:** A recombinant fusion protein of the bacterial superantigen Staphylococcal enterotoxin A (SEA) and the variable Fab fragment of the C242 monoclonal antibody. Upon administering nacolomab tafenatox, the Fab fragment binds to Lewis antigen, a glycoprotein overexpressed in human colon and pancreatic carcinoma cell surfaces, thereby directing PNU-214565 to the tumor target area and providing tumor specificity. Superantigen staphylococcal enterotoxin A (SEA) promotes the crosslinking of T-cell receptor (TCR) Vb regions with major histocompatibility complex (MHC) class II molecules on antigen presenting cells, thereby enhancing cytotoxic T-lymphocyte activation, cytokine production and tumor cell lysis.

**Synonyms:** - C242Fab-SEA Immunotoxin - NACOLOMAB TAFENATOX - PNU-214565