A material, derived from human erythrocytes and believed to be identical with the receptor site for the myxoviruses, has been obtained in homogeneous form. The method of preparation involves pH adjustment of the stroma, hot phenolic extraction, chloroform-methanol treatment, and ultracentrifugation. The material so obtained possesses a high inhibitory titer to viral hemagglutination (45,000 to ...

In this study, a novel, simple and rapid hemagglutination assay by using a peanut lectin to detect a neuraminidase activity in strains of the Bacteroides fragilis group was developed. One hundred and fourteen species of the B. fragilis group isolated from children with and without diarrhea and 15 reference strains were evaluated. Neuraminidase production was determined by using the method above...

Endogenous lactose-binding proteins from adult chicken liver and intestine have been purified to homogeneity by affinity chromatography on asialofetuinderivatized Sepharose, followed by isoelectric focusing. Since these carbohydrate-binding proteins are assayed as hemagglutinins, they are referred to by the operational term lectins. Although the hemagglutination activity of these lectins is inh...

Antigenic differences between certain inbred strains of mice which could not be revealed by hemagglutination techniques were readily disclosed by lymphocyte cytotoxicity. With an improved cytotoxicity test lymphotoxic titers were as high as 1:512 with non-hemagglutinating A anti CBA antisera. In other mouse strain combinations, a close parallel of both types of antibody activity was obtained. T...

Antibodies to streptococcal extracellular products were detected in rabbit sera by passive hemagglutination tests as early as 1 week after intravenous injection of live group A streptococci (strain C203S). Using these antibodies in immunoadsorbent columns, we prepared an antigenic fraction from crude concentrates of streptococcal extracellular products. The specific activity of this fraction in...