1. Small quantities of antiserum bring about instantaneous agglutination of pneumococci in the circulation of the rabbit; the reaction is specific and occurs in every case in which sufficient serum is given to influence the course of the septicemia or to prolong the life of the animal. 2. The agglutinating titer of antipneurnococcus serum can be made considerably higher by adding only a small q...

Magnesium oxalate agar was found to select against virulent types of Yersinia enterocolitica. Small colonies isolated from magnesium oxalate agar which were presumably virulent generally contained no detectable virulence-specific plasmids, did not agglutinate with virulence-specific antiserum, and exhibited various degrees of virulence in mice. Results indicate that the virulence potential of a...

The meningococcus, like some other pathogenic species, varies in its agglutination in immune serum, some strains being readily agglutinable while others agglutinate with difficulty in their homologous serum as well as in heterologous serums. The different strains appear to vary also in their action as antigens. In order to secure representative strains, therefore, it was thought necessary to co...

We studied hemagglutinating and adherence properties in Staphylococcus saprophyticus isolates originating from symptomatic urinary tract infections. 12/13 (92%) of strains adhered to Hep cells and 11/13 (85%) were able to agglutinate sheep erythrocytes. Adherence properties differed markedly between strains (P less than 0.0001). Two strains, one hemagglutinating and adherent and one negative fo...

Blood can form a gel when there are high concentrations of proteins, such as IgM and/or IgG antibodies, that precipitate at low temperatures (cryoglobulins) or agglutinate red blood cells (cold agglutinins) (1, 2 ). A bone marrow biopsy performed on this patient revealed Waldenström macroglobulinemia, which produces large amounts of IgM (3, 4). Warming this patient’s sample in a water bath, kee...

Human lymphoblasts in long-term culture are specifically agglutinated by concentrations of concanavalin A that do not agglutinate normal human lymphocytes. The agglutination is inhibited by a-D-methyl mannoside. Lymphoblast lines kept in long-term culture bound 2 to 3 times more concanavalin A per cell than did normal lymphocytes. Normal lymphocytes and lymphoblasts bound approximately equivale...

Epimastigotes and trypomastigotes of T. cruzi obtained from acellular culture as well as bloodstream trypomastigotes agglutinate with concanavalin A (Con A). Con A-binding sites were also localized on the cell membrane by using the Con A-horseradish peroxidase-diaminobenzidine method. Passage of epimastigotes and trypomastigotes from acellular culture through DEAE-cellulose column did not affec...

Several tissue culture cell lines that were transformed by a tumor virus have been found to react with an agglutinin, while under identical conditions their untransformed parent cell lines did not agglutinate. Since a short treatment of the parent cell line with low concentrations of proteases exposed the same agglutinin receptor sites in a fashion indistinguishable from the transformed cells, ...

A simple and economical method for differentiating Bacteroides asaccharolyticus of oral sources from nonoral sources is described. The present data indicate that oral strains of B. asaccharolyticus strongly agglutinate sheep erythrocytes, whereas isolates from various nonoral sites typically are devoid of hemagglutination activity. The direct hemagglutination test may aid in determining the sou...

the intensity of staining in frozen sections exceeds that in the corresponding fixed and embedded sections. The lectins work satisfactorily on formalinfixed material but the clarity and intensity of staining is enhanced by trypsinisation. The technique was found to be consistent and reproducible with the exception of SBA. This lectin was unpredictably prone to agglutinate in solution and fail t...