In oncology, AFP-L3 is an isoform of Alpha-fetoprotein (AFP), a substance typically used in the triple test during pregnancy and for screening chronic liver disease patients for hepatocellular carcinoma (HCC). AFP can be fractionated by affinity electrophoresis into 3 glycoforms: L1, L2, and L3 based on the reactivity with the lectin Lens culinaris agglutinin (LCA). AFP-L3 binds strongly to LCA via an additional α 1-6 fucose residue attached at the reducing terminus of N-acetylglucosamine; this is in contrast to the L1 isoform. It is the L1 isoform which is typically associated with non-HCC inflammation of liver disease condition. The L3 isoform is specific to malignant tumors and its detected presence can serve to identify patients whom need increased monitoring for the development of HCC in high risk populations (i.e. chronic hepatitis B & C and/or liver cirrhosis). AFP-L3% is now being considered as a tumor marker for the North American demographic.
AFP-L3 is isolated via an immunoassay and quantified using chemiluminesence on an automated platform. Results for AFP-L3 are represented as a ratio of LCA-reactive AFP to total AFP (AFP-L3%). The AFP-L3% assay, a liquid-phase binding assay, will help to identify at-risk subjects earlier, allowing for more intense evaluation for evidence of HCC according to existing practice guidelines in oncology. AFP-L3% is the standard for quantifying the L3 isoform of AFP in serum of high risk chronic liver... Read More