Exacerbated onset of dysentery in swine vaccinated with inactivated adjuvanted Serpulina hyodysenteriae.

After oral challenge exposure with Serpulina hyodysenteriae-infected diced colon, fewer swine vaccinated with an experimental vaccine adjuvanted with mineral oil died (8 of 25 [32%]) than did nonvaccinated controls (6 of 15 [40%]), although the difference was not significant. However, onset and exacerbation of dysentery were accelerated in vaccinated swine because: 5 of the 8 dead vaccinated swine died before any of the nonvaccinates, which was significant (P < 0.01); vaccinated swine that died were observed to have more hemorrhage in the feces, colonic mucosa, and colonic lumen than did nonvaccinated swine; and the earlier diarrhea onset in vaccinates, the more days of hemorrhagic diarrhea (P < 0.05). Antibody titer in vaccinated swine immediately before challenge exposure that subsequently died was significantly (P < 0.05) higher than that in vaccinated swine that recovered. Of of the 30 swine vaccinated with the experimental vaccine, 20 had dispersed droplets of mineral oil at the site of vaccination in the neck muscles and 3 swine had purulent abscesses at the injection site. It was concluded that vaccination with the experimental vaccine for controlling swine dysentery was ineffective.

Analysis of the common polysaccharide antigens from the cell envelope of Clostridium perfringens type A.

The major, common antigen of Clostridium perfringens type A, isolated and purified independently from three selected strains (Hobbs 5, Hobbs 9, and Hobbs 10), is composed of equimolar amounts of 2-acetamido-2-deoxy-D-mannose (Man-NAc) and 2-acetamido-2-deoxy-D-glucose (GlcNAc). The purified antigen gave a strong immunoprecipitin line by double immunodiffusion in gel. Smith degradation of the major, common antigen caused decomposition of all of the GlcNAc, without concomitant loss in ManNAc, or a perceptible change in serological activity. Therefore, the serological activity of the major, common antigen depended solely on the presence of ManNAc. Data obtained by the 13C-n.m.r.-spectral analysis of the Smith-degradation product revealed that it was a linear-backbone polysaccharide analogous to a Rhodotorula glutinis mannan, but composed of pairs of 2-acetamido-2-deoxymannopyranosyl residues alternately linked beta-(1 leads to 3) and beta-(1 leads to 4). The one-bond, carbon-hydrogen coupling-constant of 162 Hz for both anomeric centers was consistent with the proposed beta-linkages. A similar, 13C-n.m.r.-spectral analysis of the native, common antigen indicated that the GlcNAc residues were randomly connected to three of the four hydroxyl groups not already involved in linking the ManNAc backbone, the 4-hydroxyl group being the exception. A second, serologically inactive, polysaccharide composed of rhamnose, GalNAc, and galactose was identified, but not obtained in homogeneous state. The rhamnosyl residues were probably situated as nonreducing antennae, as they were quantitatively removed by Smith degradation without concomitant decomposition of the polymeric structure of the remaining residues.

Common polysaccharide antigens from the cell envelope of Clostridium perfringens type A.

Soluble antigens were obtained by extracting five serotype strains of Clostridium perfringens type A with water at 100 degrees C. The type-specific polysaccharides were precipitated with ethanol, and the common antigens were recovered from the ethanol supernatants by concentration, dialysis, and lyophilization. Refluxing the water-extracted cell residues with 1% acetic acid followed by concentration, dialysis, and lyophilization gave additional common antigen fractions. A comprehensive, side-by-side comparison of the antigen fractions, the ethanol precipitate, the ethanol supernatant, and the acetic acid supernatant, revealed that common antigens were recovered in all three fractions, and that three distinct entities were responsible for the formation of the observed common immunoprecipitin lines; whereas many fractions possessed all three immunoprecipitin lines, others contained only one or two. The serological homology observed between the various antigen fractions was apparently a consequence of N-acetylglucosamine- and N-acetylmannosamine-containing polymers. The common antigens were presumably associated with the cell envelope and may be the type of markers sought previously by others for the serological identification of C. perfringens.