Isolation, lactoperoxidase catalyzed radioiodination, and recovery of proteins bound to insoluble immunoadsorbents.

A method for the direct radioiodination and recovery of proteins specifically absorbed to an insoluble immunoadsorbent is described. The optimal conditions for adsorption, washing, radiolabelling by lactoperoxidase catalyzed iodination, and elution of radiolabelled proteins from the immunoadsorbent have been determined. The technique is a rapid and efficient means of isolating and radioiodinating specific proteins present in biological fluids and has been applied to the detection of immunoglobulin and histocompatibility antigens in mouse cell culture supernates. This method should be particularly applicable in research situations in which the specific antisera are available but the antigen concentration is low or the volume of material to be analyzed is limited.