Isolation of mouse complement component C7

Mouse complement component C7 was purified from serum by a sequential procedure of fractionation precipitation by ammonium sulfate, followed by DE-52 anion exchange chromatography, Protein G affinity column chromatography, Mono S cation exchange chromatography and Superdex 200 gel filtration. The final product contained a highly purified mouse C7 component showing a single band on SDS-PAGE at the apparent Mrs of 90 kDa and 100 kDa under non-reduced and reduced conditions respectively. The yield of C7, which was measured by the biological activity, was 7.0%.