Precipitation of proteins from salt-containing proteinaceous fluids employing a desalting treatment, and use thereof in selective plasmapheresis
AssigneeUniversity Patents, Inc.
InventorMilan Bier
Life of this patent
Estimating the term…
Abstract
Total or fractional precipitation of proteins from salt-containing proteinaceous solution or suspension mixtures is induced or enhanced by subjecting the proteinaceous mixture to a desalting treatment, for example, by electrodialysis. In one aspect of the invention, the desalting treatment is used in conjunction with the addition of heavy metal ions to the proteinaceous mixture to provide a synergistic effect on the precipitation of the protein fraction. In another aspect of the invention, the desalting treatment, either with or without the heavy metal ion addition, is employed as an integral part of a selective plasmapheresis procedure for the removal or recovery of one or more selected plasma proteins from blood plasma.
Claims28
A method for the fractionation of a proteinaceous solution or suspension mixture containing one or more salts selected from the group consisting of alkali metal salts and alkaline earth metal salts, comprising the steps of:
- (a) subjecting said proteinaceous mixture to a desalting treatment controlled so as to reduce said salt content thereof to a predetermined level;
- (b) incorporating into said proteinaceous mixture either prior or subsequent to step (a) a predetermined concentration of heavy metal ions, said predetermined level of salt content and said predetermined concentration of heavy metal ions each being selected and coordinated so that the combination thereof provides a synergistic precipitation of a protein fraction from the resulting heavy metal ion-containing desalted mixture;
- and
- (c) separating the precipitated protein fraction from the supernatant protein-impoverished mixture.
In a selective plasmapheresis method for the removal or recovery of one or more selected plasma proteins from whole blood, comprising the steps of withdrawing whole blood from a living donor, separating said whole blood into a plasma fraction and a corpuscular element fraction, treating said plasma fraction so as to remove said selected plasma proteins therefrom, recombining the resulting protein-impoverished plasma fraction with said corpuscular element fraction, and returning said recombined fractions back into the blood stream of said donor, the improvement wherein said protein-impoverished plasma fraction is obtained by the steps comprising:
- (a) subjecting said separated plasma fraction to a desalting treatment controlled so as to reduce the physiological salt content thereof to a predetermined level at which said selected plasma proteins will preferentially precipitate;
- (b) separating the precipitated protein fraction from the supernatant protein-impoverished desalted plasma fraction;
- and
- (c) reconstituting the salt balance of said protein-impoverished desalted plasma fraction back to a physiological level.
In a continuous or semicontinuous flow selective plasmapheresis apparatus including means for separating whole blood into a plasma fraction and a corpuscular element fraction, means for maintaining said blood and said fractions thereof in extracorporeal circulation, and on-line plasma treating means for effecting removal of one or more selected plasma proteins from said plasma fraction, the improvement wherein said plasma treating means comprises in combination:
- (a) plasma desalting means controllable so as to effect a reduction in the physiological salt content of said plasma fraction to a predetermined level at which said selected plasma proteins will preferentially precipitate;
- (b) means for separating the precipitated protein fraction from the supernatant protein-impoverished desalted plasma fraction;
- and
- (c) means for reconstituting the salt balance of said protein-impoverished desalted plasma fraction back to a physiological level.
Dependencies are inferred from the claim text.