Purification of the fifth component of murine complement from ascites fluid

The murine complement component C5 was purified on an affinity column using a monoclonal anti-mouse C5 antibody. We describe in this paper that ascites fluid from normal (C5-sufficient) mice contains almost as much C5 protein as mouse serum. Since ascites fluid is much easier to obtain in large quantities it is a convenient source for the purification of this mouse serum protein.