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A M Staub

Publications and source records attributed to A M Staub.

6 recordsLinked to original sources

Origin of the heterogeneity of cell wall O-polysaccharides from Salmonella zuerich (1,9,12,(46),27).

The heterogeneity of the cell wall O-polysaccharide of Salmonella zuerich (factor 1 present or absent) is probably not due to mutations in the stock since it was seen in essentially similar fashion (proportion one 1+ to four 1-forms) in four separate lots of polysaccharide extracted from separate culture batches. The results of indirect fluorescent antibody studies suggest that form variation of factor 1, occurring at an unusually high rate, is the most probable basis of the heterogeneity.

Antigens, Bacterial

Molecular immunological heterogeneity of the Salmonella zuerich [1, 9, 12, (46), 27] cell-wall polysaccharides.

Extraction of O specific polysaccharide from S. zuerich leads to three fractions (ZA, ZB, ZC). Polysaccharide ZB carries specificities 1, 27, and 46, present on the Salmonella cells. It exhibits a factor 27 that is very similar to that present on the S. typhi T2 1-minus 27-+ polysaccharide, a factor 1 that is close to that present on S. senftenberg polysaccharide, and a factor 46 that gives a very weak cross-reaction with anti-46 antibodies. Polysaccharides ZA and ZB are immunologically different and ZB contains two distinct fractions: ZB 1-minus devoid of Ofactor 1 and carrying the specificities 46 and 27 mostly, of not completely, on the same molecule (46, 27); and ZB1-+ carrying O factors 1, (46), 27. ZB 1-+ is composed of at least two different molecules: [1,(46)] precipitable with anti-1 antibodies but only coprecipitable with anti-46 antibodies; and (1, 27) precipitable with both anti-1 and anti-27 antibodies. Molecules [1, (46)] precipitate only part of the anti-1 antibodies precipitable by (1, 27). The smaller precipitation of anti-27 antibodies (when factor 27 is present together with factor 1 on the same molecule) and the coprecipitation, instead of precipitation, of anti-46 antibodies (when factors 46 and 1 are present on the same molecule) may be explained by a sterical hindrance between O-factors 1 and 27, and 1 and 46. The molecular, immunological heterogeneity of the polysaccharides extracted from S. zuerich would result from the presence on the cells of two kinds of O polysaccharides: one with, the other without O factor1, which is related to the presence of a side-chain of an alpha-D-glucosyl residue. A structure for S. zuerich polysaccharide is proposed.

ABO Blood-Group System

[Do immunization of rabbits by N-acetylgalactosamine and a disaccharide linked to a protein produce anti-microbial antibodies (author's transl)].

Rabbits were immunized with N-acetylgalactosamine linked to bovalbumine. They produced antibodies which precipitated this same sugar linked to human gamma-globulins but did not agglutinate Salmonella johannesburg which carry a side chain of N-acetylgalactosamine. The same immunization enhanced the titre of "natural" antibodies agglutinating human A red cells (which carry a terminal N-acetylgalactosamine) but they did not evoke such antibodies in rabbits with no "natural" hemagglutinins. These negative results, when compared to the positive one obtained with 0-acetyl-3,6-dideoxygalactose suggest that rabbit antibody-sites limited to one sugar may exist but that they can be detected only under certain conditions. Another group of 8 rabbits was immunized with a disaccharide alpha-Glc-(1 leads to 6)-GalNAc linked to a protein. All produced antibodies agglutinating S. johannesburg (1,40) which carry this disaccharide and S. senftenberg which carry the disaccharide alpha-Glc-(1 leads to 6)-Gal. The titres of these antibodies decreased after a second course of immunization.

ABO Blood-Group System

[Specific blast transformation of rabbit spleen cells induced by a bacterial polysaccharide and inhibitory effect of peripheral blood lymphocytes (author's transl)].

Following immunization with bacteria (i.e. Salmonella johannesburg), rabbit spleen lymphocytes developed a specific blast response when the lymphocytes were stimulated with polysaccharide, the haptenic moiety of lipopolysaccharide. A clear cut dissociation was noted in the blast response induced by polysaccharide compared with those induced by lipopolysaccharide and lipid A. There was no correlation between the magnitude of the cellular responses and that of the antibody response. Moreover, there was less specificity at the cellular level than at the level of antibody secreted by cells. A decrease of 3H-thymidine incorporation was often observed after immunization, at the level of peripheral blood lymphocytes. An inhibitory effect of these cells was shown on the blast response of spleen lymphocytes with polysaccharide. A high blast response to Salmonella polysaccharide which could be observed in some non-immunized rabbits might be related to a natural sensitization of animals with the same or related unknown antigens which could not be recognized by anti-S. johannesburg antibodies.

Animals

[Study of X antigen of Salmonella typhi responsible for the production of protective antibody towards chick embryo].

Laboratory animals are not sensitive to human S. typhi strain (O+ Vi+). But the chick embryo is very susceptible to infection by this strain. This property can be used to test protective activity of immuno sera. Several antigenic fractions have been prepared from Ty6S strain (0- Vi+) by washing methods. The " outer layer " of the bacteria is easily removed by NaCl 0,5 M. Injected in rabbits this preparation produces the synthesis of protective antibodies. The active antigen X is spun down with the Vi antigen. The relation of X antigen to Vi antigen is being studied.

Animals