Pathway: Ficolins bind to repetitive carbohydrate structures on the target cell surface
Reactions in pathway: Ficolins bind to repetitive carbohydrate structures on the target cell surface :
Ficolins bind to repetitive carbohydrate structures on the target cell surface
Ficolins are recognition molecules in the lectin pathway of complement activation. Three types of ficolin have been identified in humans: M-ficolin (ficolin-1, FCN1), L-ficolin (ficolin-2, FCN2) and H-ficolin (ficolin-3, FCN3). FCN2 and 3 circulate in blood plasma whereas FCN1 is locally secreted by immune response cells (Teh et al. 2000, Liu et al. 2005, Matsushita et al. 2002). Plasma ficolins circulate as complexes with MBL-associated serine proteases (MASPs). Upon binding of ficolins to carbohydrates on the target cell surface, MASPs are activated and subsequently activate the complement cascade (Matsushita et al. 2002, Gout et al. 2009). Ficolins function as trimers and larger oligomers. Ficolin peptide sequences contain an amino-terminal cysteine-rich region, a collagen-like domain, a neck region and a carboxy-terminal fibrinogen-like domain. The fibrinogen-like domain binds to pathogen- or apoptotic cell-associated molecular patterns. Different ficolins have distinct recognition specificities (Endo et al. 2007, Thiel and Gadjeva 2009, Garlatti et al. 2010).
Innate immunity encompases the nonspecific part of immunity tha are part of an individual's natural biologic makeup
Humans are exposed to millions of potential pathogens daily, through contact, ingestion, and inhalation. Our ability to avoid infection depends on the adaptive immune system and during the first critical hours and days of exposure to a new pathogen, our innate immune system.