Properdin

Properdin is a protein found in human blood plasma and considered an important part of the body's immune response. It is a key factor in the classical pathway of the complement system, which is responsible for recognizing and eliminating pathogens. Properdin plays a role in amplifying the response of other components of the complement system, such as triggering the activation of the membrane attack complex (MAC). Properdin also exists in several other species, including cows, rabbits and some fishes. Its presence is essential for the activation of the classical pathway and proper functioning of the immune system, thereby helping to protect the body against invading microorganisms and foreign particles. In humans, properdin deficiency has been associated with various types of autoimmune diseases, and is actively studied for its connection with these conditions.