Copurification of P6, MRP8, and MRP14 from human granulocytes and separation of individual proteins.

A method is described for purification of P6, MRP8, and MRP14, three calcium-binding proteins assigned to the S100 protein family. The purification procedure included preparation of human granulocytes, ammonium sulfate precipitation, and anion-exchange chromatography and resulted in the copurification of P6, MRP8, and MRP14. Individual proteins were separated by either preparative isoelectric focusing or preparative SDS-PAGE. The procedure was carried out in the course of 4 days and yielded several milligrams of essentially pure P6, MRP8, and MRP14 in either native or denatured form.