What is the role of control proteins in the complement system?

The role of control proteins in the complement system is primarily to prevent damage to host tissue. These control proteins function as regulators that ensure the complement cascade does not become overactivated, which could lead to excessive inflammation and tissue damage.

In the complement cascade, while active components can effectively target pathogens, they can also inadvertently harm the host's own cells if not properly regulated. Control proteins serve to inhibit the activity of specific complement components, helping to maintain a balance between an effective immune response and the protection of host tissues. For example, proteins such as factor H and CD55 can bind to active complement components and prevent them from damaging host cells.

This regulatory mechanism is crucial for preventing autoinflammatory conditions or autoimmune diseases, which can arise from inappropriate complement activation. Therefore, the presence of control proteins is essential for maintaining homeostasis and ensuring that the immune response is tailored to eliminate pathogens without causing collateral damage to the body itself.