Purification from euglobulin of the first component (C1) of complement and its subcomponents by heparin-sepharose chromatography.

Most of the C1 material of euglobulin was adsorbed to heparin-Sepharose at an ionic strength of 0.265. After desorbtion at an ionic strength of 0.415 the C1 material was found to be purified six to seven-fold. Highly purified subcomponents C1q, C1r and C1s were recovered at DEAE-Sephadex chromatography from such purified C1 material after EDTA-treatment. Tests on isolated C1q, C1r and C1s disclosed in addition to the well known interaction between heparin and C1q an equally strong or even stronger interaction between heparin and C1s. Even C1r was adsorbed to heparin although by somewhat weaker ionic bonds.