mbl

MBL is an acronym with multiple meanings across different fields. The most widely studied usage is mannose-binding lectin, a soluble protein of the innate immune system.

Mannose-binding lectin is primarily produced by the liver and circulates in the bloodstream. It binds to carbohydrate patterns on the surfaces of a broad range of pathogens, especially sugars such as mannose and N-acetylglucosamine. Upon recognition, MBL can activate the complement system via the lectin pathway through MBL-associated serine proteases (MASPs), leading to opsonization and recruitment of inflammatory responses, and in some cases to direct lysis of pathogens. Genetic variation in the MBL2 gene influences circulating levels and functional activity of the protein. Certain variants are associated with low MBL and may correlate with increased susceptibility to infections, particularly in infancy or in individuals with other immune defects. MBL levels and genotype can be studied in research and, in some clinical contexts, used to assess infection risk, although deficiency in itself is not usually diagnostic or determinative of disease.

Beyond mannose-binding lectin, MBL can be used as an acronym in other contexts to denote various organizations, products, or concepts in different fields. Because the meaning depends on context, clarifying the field is necessary to identify the intended subject.