1A3 antigen (1A3)

The 1A3 antigen is a tumor-associated cell-surface lipid antigen that is significantly enriched in human colorectal carcinoma cells. It was first identified using the murine monoclonal antibody MAb 1A3, which demonstrates high immunospecificity for colorectal adenocarcinoma and is found in over 90% of primary colorectal tumors and their metastases. Unlike many other tumor markers, the 1A3 antigen is a lipid rather than a protein, making it a unique target for diagnostic and therapeutic applications. In clinical research, the 1A3 antigen has been utilized as a target for radioimmunodetection (immunoPET) using radiolabeled versions of the 1A3 antibody, such as 64Cu-MAb 1A3. These studies have shown that the antigen is highly expressed on the surface of viable tumor cells, allowing for the detection of small tumor foci in the abdomen and pelvis. While primarily used for imaging, the high specificity and prevalence of the 1A3 antigen in colorectal cancer make it a potential candidate for targeted therapies, including radioimmunotherapy and antibody-drug conjugates.

Other names

Tumor-associated cell-surface lipid antigenColorectal carcinoma-associated lipid antigen1A3-reactive lipid antigen

Targeted binding for radioimmunodetection and potential radioimmunotherapy