Immunochemical detection of an acute-phase protein in rat serum

Abstract

A new protein designated α₂-AP (acute phase) globulin, not present in normal rat serum, has been detected by immunochemical methods in a wide variety of pathologic states. The protein is a carbohydrate-containing euglobulin and migrates with the mobility of an α₂-globulin in filter paper and agar gel. In acrylamide and starch gels it exhibits a very low mobility suggestive of a macroglobulin. It is not related antigenically to C-reactive protein or Cx-reactive protein. Possible factors responsible for the production of the protein were discussed. It was concluded that the appearance of the protein in the circulation represents a systemic manifestation of the acute inflammatory response, and that the synthesis of the protein is stimulated by substances released from injured or necrotic cells.