Patent ID: 6680376
Filing Date: 2004-01-20
Classification: C07K,Y10S

Abstract:
A process for selectively isolating antibody isoforms from egg yolk, the process comprising:(i) obtaining an aqueous fraction of egg yolk from a fowl hen egg; (ii) treating the aqueous fraction with a (NH4)2SO4 salt at a first concentration to provide a precipitate comprising a major portion of a first antibody isoform from the aqueous fraction and a resultant supernatant comprising a second antibody isoform; and (iii) salting out a major portion of the second antibody isoform from the resultant supernatant by adjusting the resultant supernatant with (NH4)2SO4 salt at a second concentration, wherein the first concentration is no more than about 21% (w/v) (NH4)2SO4 based on the volume of the aqueous fraction treated in step (ii), and the second concentration is about 31% (w/v) (NH4)2SO4 based on the volume of the resultant supernatant in step (iii), and the first antibody isoform is IgY, the second antibody isoform is IgY(&Dgr;Fc), and the ratio of IgY(&Dgr;Fc) antibodies to IgY antibodies in the salted-out material comprising the major portion of the second antibody isoform is greater or equal to 7.81.