Fixation of complement is a biological process in which the complement system is activated as a cascade of proteins which trigger a series of enzymatic reactions. The spelling of this term is based on the international phonetic alphabet (IPA) as /fɪkˈseɪʃən ʌv ˈkɒmplɪmənt/. The /k/ sound is spelled with "k", while the /ɔ/ sound is spelled with "o". The /ʃ/ sound is spelled with "sh" and the /ə/ sound is spelled with "a". Overall, the word "fixation of complement" describes an essential process in the immune system that fights against infections and foreign substances.
The fixation of complement refers to the process by which certain proteins in the blood, known as complement proteins, are activated and bind to foreign substances, such as pathogens or immune complexes. Complement proteins are an integral part of the immune system and play a crucial role in identifying and eliminating these foreign invaders.
The fixation of complement involves a series of enzymatic reactions, known as the complement cascade. It begins when specific complement proteins recognize and bind to the surface of a foreign substance, through a process known as opsonization. This binding triggers a chain reaction, leading to the activation of other complement proteins in a sequential manner.
Once activated, complement proteins produce several effects that aid in the destruction of foreign substances. These effects include the formation of membrane attack complexes, which can create pores in the cell membranes of pathogens, leading to their lysis. Complement proteins also facilitate the recruitment of immune cells to the site of infection, promoting an inflammatory response and enhancing the clearance of the foreign substance.
The fixation of complement is an important defense mechanism against infection and plays a crucial role in both innate and adaptive immunity. It helps to identify and eliminate foreign substances, enhancing the body's ability to fight off pathogens and maintain overall immune homeostasis.
See under complement.
A practical medical dictionary. By Stedman, Thomas Lathrop. Published 1920.