Serotyping of Proteus rettgeri on the basis of O antigens

Abstract

A serotyping system for Proteus rettgeri on the basis of 72 O antigens has been developed in a study of 324 strains obtained from widely distributed sources. In the investigation of the interrelations among the 72 O-type strains by cross-titration of each of the 72 anti-O sera with antigen of each of the O-type strains, both reciprocal and nonreciprocal (unilateral) reactions were observed. The presence of the Kunin common enterobacterial antigen (CA) was noted in each strain of P. rettgeri examined, and the unilateral reactions of two antisera were shown to be due to antibody present against CA. This indicated that CA was in the immunogenic state in two strains of this species. A second common antigen resembling CA in some respects but differing in specificity and in its agglutinability was shown to be the cause of unilateral reactions in a third antiserum. In other cases, unilateral reactive antibodies appeared to be directed against antigens that remained undefined. Each reciprocal reaction was investigated to determine the nature of the interrelations between interacting strains, and the definition of these led to the development of procedures for the production of absorbed anti-O sera with greater specificity. The serotyping scheme has increased the number of strains that may be typed through their O antigens, and its application in epidemiological investigations of infections due to P. rettgeri is indicated.

Cross-protection of mice provided by active and passive immunization against experimental infections with virulent Proteus rettgeri and Providencia bacteria

“…Homologous reactions, but no cross-reactions, occurred at titers of 1:40 or greater when typing antisera and six mouse antisera prepared against the six strains were cross-titrated by the passive hemagglutination (PHA) technique in which supernatant from autoclaved cell suspensions was used to sensitize sheep erythrocytes. In cross-titrations of rabbit and mouse antisera by the microtiter method of agglutination of Formalin-treated bacterial suspensions, as described previously (18), homologous reactions were observed in all cases and relations were noted between two strains, P. stuartii 024 and 055. In PHA titrations of rabbit antisera after absorptions with homologous cell suspensions heated at 121°C for 1 h, neither homologous nor heterologous reactions were observed at titers of 1:40 or greater, but homologous reactions occurred for each antiserum and crossreactions occurred between P. stuartii 024 and 055 when titration was by agglutination of bacterial suspensions (ABS).…”

“…Swiss White mice (Connaught Laboratories, Willowdale, Ontario, Canada) were injected i.p. with Formalin-treated cell suspensions prepared as described previously (18) in five doses at 5-day intervals increasing from 2.5 x 105 to 7.5 x 106 cells over the 3-week immunization period. Seven days later, mice were challenged i.p.…”

“…Antisera. Typing antisera were produced in rabbits against Formalin-treated bacterial suspensions by procedures reported previously (18,21). Mouse antisera were prepared in Swiss White mice through i.p.…”

Speciation, serotyping, antimicrobial sensitivity and plasmid content of Proteeae from the environment of calf-rearing units in South West England

“…mirabilis (Penner & Hennessy, 1980), Morganella morganii , Prov. rettgeri (Penner, Hinton & Hennessy, 1974), Prov. stuartii (Penner et al 1976) and Prov.…”

Usefulness of trehalose fermentation and L-glutamic acid decarboxylation for identification of biochemically aberrant Providencia stuartii strains

“…Serotyping. O antigens were determined as described by Penner et al (26). A total of 30 P. stuartii strains were examined by slide agglutination and passive hemagglutination.…”