HUMAN SERUM PRECIPITINS TO GOAT'S MILK PROTEINS AND TO COW'S MILK PROTEINS

Abstract

Antigenic relationships of cow's milk, cow's serum, goat's milk, and goat's serum were studied, using techniques of agar double-diffusion, DEAE-cellulose fractionation of milk proteins, and human sera containing precipitins to cow's milk. Immunologically similar proteins are present in goat's serum and cow's serum, and evidence is presented for the occurrence of crossreacting antigenic serum proteins in milk of both species. However, the samples of milk also contain other proteins, unreleated to serum proteins, which react with rabbit and human antisera.

Several human sera which contained antibodies to cow's milk were studied. Antibodies to goat's milk could be demonstrated in most of these, and to cow's serum and goat's serum in some of them. No precipitin lines were formed when rabbit or human sera were tested against commercial evaporated goat's milk, although precipitin lines were formed with reconstituted commercial dried goat's milk.

Milk samples were separated into 16 fractions by column chromatographic procedures and tested against human sera. One serum sample contained antibodies only to whey proteins while two other sera contained antibodies to all 16 fractions in both cow's milk and goat's milk.