Quantification of large C3 fragments as an index of complement activation in mice. I. In vitro studies

This paper describes a method which enables one to evaluate the mouse C3 activation. It is based on differences of solubility of native and activated C3 molecules in polyethylene glycol. The apparent molecular weights of C3 molecules detected were found to be about 230-240 kilodaltons for native C3 and 210 and 220 kilodaltons, respectively, for the two 'activated' C3 molecules. In vitro studies showed the specificity and the sensitivity of this evaluation.