I 131 Monoclonal Antibody A33

**Semantic type:** Amino Acid, Peptide, or Protein|Pharmacologic Substance

**Definition:** A radioimmunoconjugate of a humanized monoclonal antibody (MoAb) A33 labelled with Iodine 131 (I-131). MoAb A33 recognizes A33 antigen, a 43 KDa transmembrane glycoprotein of the immunoglobulin superfamily, highly and homogenously expressed in 95% of colorectal cancers, with only restricted expression in normal colonic mucosa. Using MoAb A33 as a carrier for I-131 results in the targeted imaging and/or destruction of cells expressed A33 antigen.

**Synonyms:** - Iodine I 131 Monoclonal Antibody A33