Ficolin-2 (FCN2)

Ficolin-2 (FCN2), also known as L-ficolin, is a pattern recognition receptor of the innate immune system, encoded by the FCN2 gene and secreted mainly by the liver into serum. It consists of a collagen-like stalk and a C-terminal fibrinogen-like domain; this multimeric lectin binds specifically to acetylated carbohydrate structures on microbial surfaces such as lipoteichoic acid of Gram-positive bacteria. Upon binding, Ficolin-2 assembles with MBL-associated serine proteases (MASPs), thereby activating the lectin pathway of the complement cascade and promoting opsonization and phagocytosis of pathogens. Ficolin-2 interacts with other humoral molecules (e.g., pentraxin 3) to enhance complement deposition on pathogens. Genetic polymorphisms in FCN2 significantly impact Ficolin-2 serum levels, potentially altering individual susceptibility to infectious diseases.

Other names

EBP-37P35FCNLFicolin-BFicolin-betaHucolinL-ficolinSerum lectin p35Collagen/fibrinogen domain-containing protein 237 kDa elastin-binding protein

Ligand recognition triggers assembly with MBL-associated serine proteases (MASPs), leading to complement activation and opsonization of pathogens