The Metabolism of Normal Plasma Proteins and Gamma-Myeloma Protein in Mice Bearing Plasma-Cell Tumors

Study of the synthesis, catabolism and nature of y-globulin has been facilitated by the availability in mice of transplantable plasma-cell tumors, each capable of synthesizing characteristic and different forms of plasma globulin (1). Since the use of such tumors in inbred mice readily permits mul- tiple comparable observations, a study was carried out in sufficient detail to permit evaluation of the effects of different plasma-cell tumors on the me- tabolism of individual serum proteins. The find- ings were compared with those in human multiple myeloma in which published results are few and apparently conflicting. Thus, Berson and Yalow (2) found the fractional turnover rate of a y-mye- loma protein to be approximately normal in the donor patient as well as in another patient with- out a serum myeloma protein. Lippincott and co- workers (3, 4), however, observed a rapid turn- over of normal y-globulins and -y-myeloma proteins in patients with -y-myeloma proteins. Gamma- globulin turnover was less rapid in patients with ,8-myeloma proteins. Neufeld (5) also noted a rapid turnover for globulins in a patient with a y-myeloma protein.