What is the role of complement proteins in the immune response?

The role of complement proteins in the immune response is primarily to enhance the ability of antibodies and phagocytic cells to clear pathogens. Complement proteins are part of the innate immune system and serve several functions that amplify the immune response. When activated, these proteins can opsonize pathogens, tagging them for destruction by phagocytes, which are immune cells responsible for engulfing and digesting cellular debris and pathogens.

Additionally, complement proteins can promote inflammation and assist in the formation of membrane attack complexes that can directly lyse pathogens by creating pores in their membranes. This multifaceted approach not only helps in directly eliminating pathogens but also primes the immune response, making it more effective and efficient in targeting infections.

Such enhancement is particularly important because it not only aids in the direct attack against pathogens but also ensures a more coordinated response involving various components of the immune system, including antibodies produced by B cells that can further neutralize pathogens. Therefore, the function of complement proteins is integral to both innate and adaptive immunity, reinforcing their essential role in the overall immune response.