C8 Antibody (Polyclonal)

C8 is a glycoprotein which is present in normal human serum/plasma at approximately 50 μg/mL. C8 is unique in that it is made up of 3 non-identical subunits, α, β, and γ. The molecular weights of these subunits are 64 kD, 64 kD, and 22 kD, respectively. The α and γ chains are linked together by a disulfide bond, whereas the β chain is associated to the α-γ complex by a non-covalent bond. The main function of the C8 protein is to initiate the binding of C9 to form the Membrane Attack Complex (MAC) . With activation of the classical or alternative pathways of the complement system, C5 convertase cleaves the C5 chain into C5a and C5b. C5b remains bound to the convertase and will combine with C6 to form a C5b,6 complex. This complex normally interacts with C7 to form C5b,6,7 that becomes partially embedded in the target cell outer membrane. The C5b,6,7 complex will subsequently bind C8 and multiple C9 molecules completing the terminal pathway. The C5b,6,7,8,9, or C5b-9 complex, is also known as the Membrane Attack Complex (MAC), which causes irreversible damage to the target cell membrane.

The anti-human C8 polyclonal antisera was tested against normal human plasma by double immunodiffusion, one-dimensional immunoelectrophoresis, quantitative radial immunodiffusion, and quantitative rocket immunoelectrophoresis. The antiserum was determined to be monospecific for C8 at varying concentrations.