Letter from Enrique E. Ecker, Western Reserve University to Michael Heidelberger

In this letter, Ecker discussed matters of evidence, interpretation, and priority in the young field of complement research, a field in which Heidelberger's and Ecker's laboratories played leading roles during the 1940s. Ecker wrote in response to criticism of his laboratory's findings offered in a forthcoming article by Heidelberger, Otto Bier, one of Heidelberger's former postdoctoral researchers, and others. Heidelberger helped launch the field of complement chemistry during the late 1930s and early 1940s by proving that complement actually existed, and was a group of specific chemical substances that could be isolated in the laboratory. Subsequent research has shown that complement is a complex system of over twenty serum proteins that after activation had an essential enzymatic function in host defense mechanisms against invading microorganisms, namely in the promotion of inflammation, phagocytosis (the engulfing of invading organisms by immune cells), and lysis (the breaking up of such organisms).