STUDIES ON AGGLUTINATION OF TOXOPL,4$MA GONDII BY

A direct agglutiaation test for Toxoplasma gondii was described by FULTON and TURK (1959) in a preliminary communication, and has since been further developed. The antigen consists of a suspension of the parasites free from other cells, which can be used equally well in the complement-fixation test (FULTON and SUTTON, 1962). The results obtained in the direct agglutination test have shown good correlation with other serological tests commonly used in the detection of Toxoplasma antibodies, including the fluorescent antibody test (FULTON and VOLLER, 1964). The specificity of the agglutination test has been studied by immunization and absorption procedures and by the use of sera from other parasitic infections. The occurrence of agglutinins in sera, in the absence of known antigenic stimulus, has also been investigated, and these have been termed natural agglutinins. Materials and methods Antigen The method of preparation was essentially that of FULTON and SPOONER (1960), in which the RH strain of Toxoplasma gondii was isolated from the peritoneal exudate o