The antigenicity of rat collagen.

A method is described for preparing purified collagen from the tail tendons of rats with minimal alteration from its native state. This purified collagen is soluble in dilute acetic acid and when injected intraperitoneally into rabbits induces complement-fixing antibodies in low titer. It has been demonstrated by the use of certain immunological tests, enzymatic analyses, and electron microscopy that these antibodies are probably directed specifically toward collagen rather than toward accompanying impurities such as tissue proteins or polysaccharides. Evidence is presented suggesting that collagen exhibits species specificity.