THE ELECTROPHORETIC COMPOSITION OF GUINEA PIG SERUM: EFFECTS OF HEAT INACTIVATION, DECOMPLEMENTATION, AND AGING

Abstract

The proteins of normal guinea pig serum have been characterized by several electrophoretic methods, and the effects of aging, decomplementation, and heat inactivation investigated. Storage at 4 °C for 2 weeks, decomplementation with a specific antigen–antibody precipitate, and heating at 56 °C for 30 minutes resulted in a loss of 64, 92, and 100%, respectively, of hemolytic complement activity. Moving-boundary analyses demonstrated an apparent increase of γ-globulin in the decomplemented serums. Heat inactivation caused the disappearance of the α1-globulin fraction concomitant with pronounced apparent decreases in the albumin and β-globulin fractions and a conspicuous increase in the α2-globulin area.Filter paper electrophoresis revealed an apparent increase in the α2-globulins and a decline in the γ-globulin fraction in decomplemented serums. In heated serums the concentration of the albumin and γ-globulin fractions apparently decreased and levels of the α2- and β-globulins were elevated. Twenty-one bands were observed in normal guinea pig serum by the starch gel technique. Decomplementation resulted in the loss of 1 band, and heat inactivation caused an alteration in 11. Four precipitin arcs, termed α0, β2-I, β1-IV, and β1-X, were affected in the immunoelectropherograms when complement activity was altered. Aging elicited the appearance of a new precipitin arc, β1-X, and a decrease in the mobility of β1-IV. A decrease in the mobility of the β1-IV arc was observed in decomplemented serums. Heating caused the disappearance of two precipitin lines, α0 and β1-V, an increase in the electrophoretic mobility of β1-I, and a decrease in the rate of migration of the β1-IV arc.