A Hæmoglobin-binding β-Globulin in Human Serum

Abstract

A NUMBER of human serum proteins have the property of forming definite compounds with hæmoglobin. The term haptoglobin has been applied to them by Jayle^1,2, who was able to isolate them by salt fractionation and characterize them as α₂-globulins by electrophoresis. In several studies using paper electrophoresis, hæmoglobin-binding proteins have been detected in the α₂ region. Hæmoglobin has also been found in the β-globulin region, especially when large amounts are present, but since free hæmoglobin itself migrates as a β-globulin, it has been assumed that this represents uncombined hæmoglobin. Neale, Aber and Northam³ found that a discrete band in the β-globulin region reacted with benzidine reagents, but did not appear to be free hæmoglobin. They suggested that a β-globulin binds hæmoglobin as well as an a α₂-globulin.