Studies on the A-Antigenic Polysaccharide from the Abomasus of Cattle

[摘要] From the mucosa of the cow's fourth stomach, the abomasus, a polysaccharide has been prepared which exerted a strong neutralizing effect on α-agglutinins of B-serum and on anti-A and anti-sheep hemolysins. It was active in a dilution of 1:1 million. Its action on the β-agglutinins of A-serum was 100 times weaker.The protein-free polysaccharide was inhomogeneous. It contained 20–25 percent of chondroitin- or mucoitin-sulphuric acid. The remainder was a neutral polysaccharide and contained about equal parts of acetylated glucosamine and another sugar, possibly galactose. The presence of mannose could be excluded by means of the Dische reaction.The antigenic properties of the crude polysaccharide were not destroyed by mild treatment with alkali nor through OH-acetylation and subsequent deacetylation. They were, however, immediately destroyed on boiling with N or 0.1 N acid. Consequently, the high molecular polysaccharide structure is essential to the A-effect of the antigen.When the polysaccharide was submitted to cataphoretic migration it was fractionated into strongly acid fractions containing chondroitin- and mucoitinsulphuric acid and into neutral fractions. Strangely enough, all fractions showed the same neutralizing effect on α-iso-agglutinins and on hemolysins. The neutralizing effect on the α-agglutinins and on the hemolysin, although strong, was not clear-cut, indicating some kind of incompleteness in the antigenic picture. Evidently the A-property occurring in the erythrocyte membrane, in saliva, and in urine has a more complete structure.

[学科分类] 生物科学（综合）