This can contribute to some disease proceses. The action of complement much be confine to designated targets because once activated, complement s activity is non-specific. Many of the proteins that regulate complement are described in Table 13-6 . 1. One intrinsic aspect that contributes to regulation is the inherent instability of intermediary components. For example, C3b s site for attachment to membranes becomes inactive by the time it diffuses 40 nm away from the C3 convertase that generated it.
Inhibitory proteins exist.
For example, C1InH formas a complex with C1r2s2 and promotes its dissociation from C1q. Inhibits classical pathway. There is a whole family of C3 convertase regulators. This is an important step at which to regulate complement since it prevents the major amplification step . The pathways of action of several of these are illustrated in Figure 13-10.