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.