FURTHER STUDIES OF THE GAMMA-RELATED PROTEINS OF NORMAL URINE

Abstract

The urinary proteins which are anti-genically related to plasma gamma globulins are divisible into 2 groups on the basis of molecular size. The large molecules appear to be 75 gamma globulin, derived from the corresponding protein of plasma. The smaller molecules ("gamma-[mu] protein") resemble Bence Jones proteins in molecular size, thermosolubility and antigenic structure. As defined by reactions with rabbit antiserum to plasma gamma globulins, the antigenic structure of gamma- [mu] protein appears to include all determinants represented on the different antigent antigenic types of Bence Jones proteins, and no other determinants. Material resembling gamma-[mu] protein in molecular size and antigenic structure .has also been identified in serum and cerebrospinal fluid. An isotopic study suggested that gamma-[mu] protein is not a breakdown product of larger plasma gamma globulin molecules.