A simple method for isolation of human properdin by affinity chromatography.

Human properdin was prepared from the zymosan eluate or euglobulin fraction of serum by immunoadsorbent column chromatography. An immunoadsorbent column containing antibody to human serum was employed to remove serum proteins other than properdin from zymosan eluates. Immunoadsorbent with antibody to properdin was used for direct isolation of properdin from the euglobulin fraction. Properdin isolated by these methods showed satisfactory purity with high activity. No immunochemical differences between the two types of preparation were found.