Mannose-binding lectin (MBL), also known as mannose-binding protein (MBP), is a calcium-dependent oligomeric protein that belongs to the collectin family of proteins. It contains a collagen-like domain and a carbohydrate recognition domain, Enabling MBL to recognize carbohydrates (for example, MBL can activate complement pathways that are not related to classical and alternative complement activation pathways by using linked mannose-binding lectin-associated serine protease (MASP-2) in antibodies and C1q-. MASP- 2 Allow C4 and C2 to be cleaved to form C3 convertase. Once bound, MBL exhibits complement-dependent antibacterial activity, such as microbial opsonization and/or microbial lysis through membrane attack complexes, thus innate immunity.
In humans, MBL is encoded by a single gene, while in mice, there are two homologous proteins called MBL-A and MBL-C. The concentration of MBL-A in serum is about 6 times lower than that of MBL-C. In casein and LPS injection models, MBL-A is an acute phase protein, but not MBL-C. In addition, MBL-A-deficient mice have been shown to have abnormal antigen-specific IgM responses and increased sensitivity to infection. Please note that monoclonal antibody 8G6 is a calcium-dependent antibody.