Cross-reactions of lipopolysaccharides of Pseudomonas aeruginosa in antipneumococcal and other antisera.

Lipopolysaccharides of the seven Fisher immunotypes of Pseudomonas aeruginosa gave cross-precipitation in many antipneumococcal sera. The reaction of Pseudomonas type IV in type 25 antipneumococcal serum was immediate and heavy: 93 micrograms of antibody nitrogen per ml. Correlations are described, mainly between the structures of the O-chains of the immunotypes and their specificities as shown by the cross-reactions.

Crossreactions of Escherichia coli K and O polysaccharides in antipneumococcal and anti-Salmonella sera.

Crossreactions of 24 K polysaccharides and 4 O polysaccharides of E. coli in antisera to 27 pneumococcal types, 3 anti-Salmonella sera, and anti-Klebsiella Kl serum are discussed in relation to structural features of the polysaccharides insofar as these are known. Predictions based on the crossprecipitations are also ventured for several instances in which structures are as yet undetermined.

Cross-reactions of polysaccharides of staphylococci and streptococci in antipneumococcal and other antisera.

Relationships between chemical structure and immunological specificity, deduced from cross-precipitation with antibodies to polysaccharides of known structure, are drawn for polysaccharides of strains of staphylococci and of groups D and H streptococci.

Cross-reactions of polysaccharides of fungi, molds, and yeasts in anti-pneumococcal and other antisera.

Cross-reactions of a number of glycans and polysaccharides isolated from fungi, molds, and yeasts in anti-pneumococcal and other antisera are tabulated and discussed insofar as possible with relation to the chemical structures of the cross-precipitating substances and the polysaccharidic antigens giving rise to the reactive antibodies. For example, the slime of Physarum polycephalum precipitated antisera to pneumococcal type 4 and Klebsiella type K1. The polysaccharides of type 4 and K1 contain pyruvic acid in acetal linkage on hydroxyls 2 and 3 of sugars. Therefore, pyruvic acid was looked for and found in Physarum slime. Numerous other relations between chemical structure and immunological specificity are given.

Precipitating cross-reactions among pneumococcal types.

Data accumulated over many years are brought together on cross-reactions of 46 among the more than 80 pneumococcal serological types, with the idea of correlating cross-reactions with the structures of the relevant type-specific capsular polysaccharides, insofar as these have been determined. The precipitin reaction was carried out with the polysaccharides and antibodies raised in horses, rabbits, and a mule. Quantitative values (micrograms of antibody nitrogen per milliliter of antiserum at 0 to 1 degree C) are given in many instances and discussed, together with arbitrary qualitative data, in terms of the known structures of the polysaccharides. Some precise relationships are uncovered, and an attempt is made to determine why some of the cross-reactions are reciprocal and why others are only unilateral.

Immunochemical determination of the configuration of a haptenic substituent.

Quantitative inhibition of specific immune precipitation, a rapid microanalytical technique requiring no expensive equipment, was used to determine the stereoconfiguration of pyruvyl groups attached as acetals to two hydroxyls of nonreducing lateral end groups of the capsular polysaccharides of Klebsiella serotypes K11 and K21. The R and S isomers of 4,6-O-pyruvyl-D-alpha-methylgalactoside were used as inhibitors with appropriate polysaccharide antigens and antisera to the two serotypes. The R isomer was a potent inhibitor of precipitation in both antisera, showing that the pyruvylgalactosyl residues in the polysaccharides of both K11 and K21 are in the R form, in which the methyl group of pyruvyl is equatorial to the plane of the acetal ring.

More on cross-reactions of Pneumococci and Klebsiella.

Earlier studies are extended to the higher-numbered K-types of Klebsiella, several of which may now be fitted into the previously found groups. Additional correlations between chemical structure and serological specificity are given, not only among the higher K-types, but also for several which were previously uninterpretable because structures were not known at the time. K1, K5, K6, K7 and K56 are shown to form a related group, although the reasons for their cross-reactivities are not always the same.

Homologous and cross-reactive precipitins in anti-pneumococcal sera raised in mules.

Serial bleedings were obtained from two mules during prolonged immunization, one with type XXV the other with type VIII pneumococcal vaccine. IgGa, IgGb, IgGc, IgB, IgG(T) and IgM present among purified Pn anti-XXV and Pn anti-VIII immunoglobulin isolated from various bleedings were identified by use of rabbit anti-equine heavy chain specific reagents. Radioimmunodiffusion with 14C-labelled type XXV pneumococcal capsular polysaccharide and horse and donkey reagents with species specificity directed against donkey or horse IgGa respectively, demonstrated both parental horse and donkey IgGa heavy chain isotypes among the anti-PnXXV antibodies of the interspecies hybrid. Qualtitative and quantitative examination of the cross-precipitation of mule anti-PnXXV sera with the capsular polysaccharides of pneumococcal types IV, X and XA, with birch sap, ketha gum, and with polysaccharides of E. coli, Klebsiella and Rhizobium was carried out and compared with data obtained with anti-PnXXV raised in a horse. Analysis of supernatants from the cross-reactions showed that distinct subfractions had reacted. indicating a marked heterogeneity of the antibodies.

[Cross reactions of higher type-specific capsular polysaccharides of Klebsiella in antipneumococcal sera]. / Réactions-croisées supplémentaires entre les polysides capsulaires de Klebsiella et les sérums antipneumococciques

Qualitative and quantitative precipitin reactions are given of the polysaccharides K60, K61, K65, K67-69, K70, K71, K73, and K83, also of depyruvylated K1. As expected, the last reacts more strongly in antipneumococcal (anti-Pn) VIII and X than does intact K1. K65 and K67 precipitate much of the same large fraction of anti-PnXXIII as does K47, showing that K65 and K67 also possess lateral non-reducing end-groups of L-rhamnose. The massive reaction of K83 in anti-PnII confirms the chemically demonstrated non-reducing end-groups of D-glucuronic acid in the repeating unit, Such groups, or 1,2-linked D-glcA, will probably also be found in K71.