Adsorption and Aggregation of Gamma Globulin onto Chylomicrons in Serum of Lowered Ionic Strength †

In the course of experiments involving centrifugation of fresh postprandial human serum diluted with isotonic sucrose, an unexpected phenomenon was noted; the usual opaque fat layer at the surface was missing, and a white pellet was deposited at the bottom of the tube. Microscopic and chemical examinations revealed the deposit to be composed of chylomicrons. Further study of this phenomenon demonstrated that lowering the ionic strength of serum led to adsorption of gamma globulin onto chylomicrons, with resulting increase in their density. This adsorbed gamma globulin was, at least in part, aggregated as evidenced by its biological activity.