Complement component 4 is a protein involved in the complement system.It is cleaved into proteins 4a and 4b; 4b can be further cleaved into 4c and 4d. C4a is an anaphylatoxin. C4b forms part of C3-convertase in conjunction with 2a: C4b can bind CR1.
This page contains content from the copyrighted Wikipedia article "Complement component 4"; that content is used under the GNU Free Documentation License (GFDL). You may redistribute it, verbatim or modified, providing that you comply with the terms of the GFDL.