Monoclonal antibody 7g1 recognizes human m-ficolin, also known as ficolin-1. Ficollins are a family of pattern recognition molecules, which contain both collagen like domain and fibrinogen like domain. They can activate the complement system on the surface of microorganisms by binding with MASPS. In humans, there are three known ficolins: m-ficolin, L-ficolin (ficolin-2) and h-ficolin (ficolin-3). M-ficolin was mainly expressed by monocytes, granulocytes and lung cells, and localized in the inflammatory area. However, this has recently been found in serum, suggesting that m-ficolin also plays a role in systemic immunity, just like L-and h-ficolin. Functional analysis of m-ficolin showed that its ligand was sialic acid, which existed in bacteria because the binding was eliminated when the bacteria were treated with sialidase. In addition, studies have shown that m-ficolin can promote the uptake of E.coli by leukemia monocyte lymphoma cells, which indicates that it acts as a phagocytic receptor on the surface of circulating monocytes. Low concentrations of m-ficolin in cord blood are associated with higher mortality associated with necrotizing enterocolitis, and two identified SNPs in the m-ficolin gene are associated with the development of rheumatoid arthritis. Monoclonal antibody 7g1 is suitable for immunoassay and Western blotting. -