Capnocytin

Capnocytin is a protein found in the blood plasma of various mammals. It is a component of the complement system, a complex network of proteins that plays a crucial role in the innate immune response. Specifically, capnocytin is involved in the lectin pathway of complement activation. This pathway is triggered by the binding of lectins, such as mannose-binding lectin (MBL), to carbohydrate structures on the surface of pathogens.

Upon activation, capnocytin participates in a cascade of enzymatic reactions that ultimately lead to the formation of the membrane attack complex (MAC). The MAC can directly lyse (destroy) bacterial cell membranes. Additionally, complement activation involving capnocytin generates other biologically active fragments that can opsonize pathogens, making them more easily recognized and phagocytosed by immune cells, and can also attract immune cells to the site of infection through chemotaxis. While primarily a defense mechanism, dysregulation of the complement system, including components like capnocytin, has been implicated in various inflammatory and autoimmune diseases. Research continues to explore the precise roles and therapeutic potential of capnocytin and other complement proteins.