Monoclonal antibody C9-5-48 recognizes mouse complement component C9. The complement system is an ancient pro-inflammatory and microbial destruction system that can be considered part of the innate and adaptive immune system. It consists of classical, alternative and lectin binding pathways. Each pathway is triggered in a unique way, but all C3 fragments are deposited on the target and bind to a common terminal sequence called TCC or "membrane attack complex" (MAC). In contrast to activation pathways that require enzymatic cleavage, the final pathway relies on conformational changes induced by the binding of different subunits. TCC is composed of a complex of 4 complement proteins (C5b, C6, C7 and C8). These proteins bind to the outer surface of the target plasma membrane, and there are many copies of the fifth protein (C9) connected to each other to form a loop in膜上. The membrane. The ring structure formed by C9 is a pore in the membrane that allows molecules to diffuse freely in and out of the cell. If enough pores are formed, the cells will not survive. When the complement protein C5 convertase cleaves C5 into C5a and C5b, it initiates the membrane attack complex. The binding of C6 promotes the binding of C7, which changes the conformation of the complex. After C8 is combined, a variable number of C9 molecules associate with the C5b678 complex to form TCC. The formation of TCC causes cell lysis or can trigger a variety of cellular metabolic pathways, leading to the synthesis and release of inflammatory mediators.