Isolation of lipid-free C-reactive protein by affinity chromatography

Human C-reactive protein purification has been hampered by its association with lipids. Isolation of pure lipid-free C-reactive protein was obtained by a three step procedure. First, partially lipid-free C-reactive protein was obtained by affinity chromatography from ascitic fluids; second, lipid-bound proteins were eliminated by calcium-dependent precipitation; and third, lipid-free pure C-reactive protein was obtained by affinity re-chromatography of the supernatant. A 46-50% yield of lipid-free C-reactive protein was obtained compared with the 14.7% obtained by the old method of extraction with lipid solvents.