Purification of three porcine immunoglobulin classes from the same biological source.

Porcine IgG, IgA and IgM were isolated from sow milk. They were systematically purified by a combination of gel filtration and ion exchange chromatography. The yields were 85%, 64% and 32%, respectively. These immunoglobulins were very pure, as checked by SDS-PAGE and Ouchterlony immunodiffusion. SDS-PAGE showed moreover the evidence of secretory component S in the IgA molecule and of joining piece J both in IgA and IgM molecules. The procedure can be used to purify immunoglobulin classes from other biological sources.