Enterotoxigenic Escherichia coli (ETEC) is one of the most important causes of post-weaning diarrhea in piglets. Whilst serotype O149:F4 is frequently associated with hemorrhagic gastroenteritis, other serotypes have been found to be associated with mild or moderate enteritis. As neutrophils are recruited to sites of inflammation, the aim of this study was to ascertain whether or not there is any difference in the in vitro interaction between neutrophils and two different ETEC serotypes: O149:F4 and O147:F18. The association of bacteria with neutrophils was evaluated by flow cytometry. The respiratory burst was measured by the fluorescent probe dichlorofluorescein diacetate using flow cytometry and by L012-amplified chemiluminescence. The titers of antibodies against ETEC present in cultivation sera were assessed by agglutination. The viability of E. coli was ascertained by cultivation. It was found that the strains of O149 serotype were more frequently associated with neutrophils and induced a more intensive respiratory burst compared to the strains of O147 serotype. These differences might be due to the presence of different types of fimbriae on the surface of the strains tested and by the presence of anti-fimbrial antibodies in the porcine plasma. However, the intensive interaction between E. coli and the neutrophils and respiratory burst induced by the O149 strain did not lead to more efficient killing of the bacteria. It is suggested that a stronger respiratory burst may be an important factor causing severe clinical signs of post-weaning diarrhea in piglets.
- MeSH
- Fimbriae, Bacterial immunology MeSH
- Enterotoxigenic Escherichia coli immunology MeSH
- Escherichia coli Infections blood immunology microbiology veterinary MeSH
- Swine Diseases blood immunology microbiology MeSH
- Neutrophils immunology microbiology MeSH
- Swine MeSH
- Escherichia coli Proteins blood immunology MeSH
- Diarrhea blood immunology microbiology veterinary MeSH
- Animals MeSH
- Check Tag
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
Porcine pleuropneumonia caused by Actinobacillus pleuropneumoniae accounts for serious economic losses in the pig farming industry worldwide. We examined here the immunogenicity and protective efficacy of the recombinant type IV fimbrial subunit protein ApfA as a single antigen vaccine against pleuropneumonia, or as a component of a multi-antigen preparation comprising five other recombinant antigens derived from key virulence factors of A. pleuropneumoniae (ApxIA, ApxIIA, ApxIIIA, ApxIVA and TbpB). Immunization of pigs with recombinant ApfA alone induced high levels of specific serum antibodies and provided partial protection against challenge with the heterologous A. pleuropneumoniae serotype 9 strain. This protection was higher than that engendered by vaccination with rApxIVA or rTbpB alone and similar to that observed after immunization with the tri-antigen combination of rApxIA, rApxIIA and rApxIIIA. In addition, rApfA improved the vaccination potential of the penta-antigen mixture of rApxIA, rApxIIA, rApxIIIA, rApxIVA and rTbpB proteins, where the hexa-antigen vaccine containing rApfA conferred a high level of protection on pigs against the disease. Moreover, when rApfA was used for vaccination alone or in combination with other antigens, such immunization reduced the number of pigs colonized with the challenge strain. These results indicate that ApfA could be a valuable component of an efficient subunit vaccine for the prevention of porcine pleuropneumonia.
- MeSH
- Actinobacillus pleuropneumoniae genetics immunology pathogenicity MeSH
- Adhesins, Bacterial genetics immunology MeSH
- Fimbriae, Bacterial genetics immunology MeSH
- Bacterial Vaccines genetics immunology MeSH
- Escherichia coli genetics MeSH
- Exotoxins genetics metabolism MeSH
- Virulence Factors genetics immunology MeSH
- Actinobacillus Infections immunology prevention & control veterinary MeSH
- Molecular Sequence Data MeSH
- Swine Diseases immunology prevention & control MeSH
- Pleuropneumonia immunology prevention & control veterinary MeSH
- Polymerase Chain Reaction veterinary MeSH
- Swine MeSH
- Recombinant Proteins genetics immunology MeSH
- Sequence Analysis, DNA veterinary MeSH
- Vaccination veterinary MeSH
- Animals MeSH
- Check Tag
- Male MeSH
- Female MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Randomized Controlled Trial MeSH
A large outbreak caused by a rare Shiga toxin-producing Escherichia coli serotype O104:H4 occurred in Germany in May to July 2011. The National Reference Laboratory for E. coli and Shigella investigated the stool sample from an American tourist with bloody diarrhea who arrived in the Czech Republic from Germany where she consumed salads with raw vegetable a week ago. Using culture of the enriched stool on extended-spectrum β-lactamase agar, we isolated E. coli strain which belonged to serotype O104:H4 as determined by conventional and molecular serotyping. The strain contained the major virulence characteristics of enterohemorrhagic E. coli (stx (2) encoding Shiga toxin 2) and enteroaggregative E. coli (aggA encoding aggregative adherence fimbriae I). This unique combination of virulence traits demonstrated that this strain belongs to the hybrid enteroaggregative hemorrhagic E. coli clone which caused the German outbreak. Using advanced culture and molecular biological approaches is the prerequisite for identification of new, unusual pathogens.
- MeSH
- Enterohemorrhagic Escherichia coli genetics isolation & purification physiology MeSH
- Disease Outbreaks MeSH
- Escherichia coli genetics isolation & purification physiology MeSH
- Escherichia coli Infections epidemiology microbiology MeSH
- Middle Aged MeSH
- Humans MeSH
- Diarrhea epidemiology microbiology MeSH
- Recombination, Genetic MeSH
- Shiga Toxin 2 genetics metabolism MeSH
- Check Tag
- Middle Aged MeSH
- Humans MeSH
- Male MeSH
- Female MeSH
- Publication type
- Journal Article MeSH
- Case Reports MeSH
- Geographicals
- Czech Republic MeSH
- Germany MeSH
Enteroaggregative Escherichia coli (EAEC) strains including those of serogroup O111 are important causes of diarrhea in children. In the Czech Republic, no information is available on the etiological role of EAEC in pediatric diarrhea due to the lack of their targeted surveillance. To fill this gap, we determined the proportion of EAEC among E. coli O111 isolates from children with gastrointestinal disorders ≤ 2 years of age submitted to the National Reference Laboratory for E. coli and Shigella during 2013-2022. EAEC accounted for 177 of 384 (46.1 %) E. coli O111 isolates, being the second most frequent E. coli O111 pathotype. Most of them (75.7 %) were typical EAEC that carried aggR, usually with aaiC and aatA marker genes; the remaining 24.3 % were atypical EAEC that lacked aggR but carried aaiC and/or aatA. Whole genome sequencing of 11 typical and two atypical EAEC O111 strains demonstrated differences in serotypes, sequence types (ST), virulence gene profiles, and the core genomes between these two groups. Typical EAEC O111:H21/ST40 strains resembled by their virulence profiles including the presence of the aggregative adherence fimbriae V (AAF/V)-encoding cluster to such strains from other countries and clustered with them in the core genome multilocus sequence typing (cgMLST). Atypical EAEC O111:H12/ST10 strains lacked virulence genes of typical EAEC and differed from them in cgMLST. All tested EAEC O111 strains displayed stacked-brick aggregative adherence to human intestinal epithelial cells. The AAF/V-encoding cluster was located on a plasmid of 95,749 bp or 93,286 bp (pAAO111) which also carried aggR, aap, aar, sepA, and aat cluster. EAEC O111 strains were resistant to antibiotics, in particular to aminopenicillins and cephalosporins; 88.3 % produced AmpC β-lactamase, and 4.1 % extended spectrum β-lactamase. We conclude that EAEC are frequent among E. coli O111 strains isolated from children with gastrointestinal disorders in the Czech Republic. To reliably assess the etiological role of EAEC in pediatric diarrhea, a serotype-independent, PCR-based pathotype surveillance system needs to be implemented in the future.
- MeSH
- Anti-Bacterial Agents pharmacology MeSH
- Escherichia coli * genetics isolation & purification pathogenicity classification MeSH
- Virulence Factors genetics MeSH
- Gastrointestinal Diseases microbiology MeSH
- Genome, Bacterial MeSH
- Escherichia coli Infections * microbiology epidemiology MeSH
- Infant MeSH
- Humans MeSH
- Multilocus Sequence Typing MeSH
- Infant, Newborn MeSH
- Child, Preschool MeSH
- Escherichia coli Proteins genetics MeSH
- Diarrhea * microbiology MeSH
- Whole Genome Sequencing * MeSH
- Serogroup MeSH
- Trans-Activators MeSH
- Check Tag
- Infant MeSH
- Humans MeSH
- Male MeSH
- Infant, Newborn MeSH
- Child, Preschool MeSH
- Female MeSH
- Publication type
- Journal Article MeSH
- Geographicals
- Czech Republic MeSH
Despite more than 50 years of vaccination, pertussis is still an endemic disease, with regular epidemic outbreaks. With the exception of Poland, European countries have replaced whole-cell vaccines (WCVs) by acellular vaccines (ACVs) in the 1990s. Worldwide, antigenic divergence in vaccine antigens has been found between vaccine strains and circulating strains. In this work, 466 Bordetella pertussis isolates collected in the period 1998-2012 from 13 European countries were characterised by multi-locus antigen sequence typing (MAST) of the pertussis toxin promoter (ptxP) and of the genes coding for proteins used in the ACVs: pertussis toxin (Ptx), pertactin (Prn), type 2 fimbriae (Fim2) and type 3 fimbriae (Fim3). Isolates were further characterised by fimbrial serotyping, multi-locus variable-number tandem repeat analysis (MLVA) and pulsed-field gel electrophoresis (PFGE). The results showed a very similar B. pertussis population for 12 countries using ACVs, while Poland, which uses a WCV, was quite distinct, suggesting that ACVs and WCVs select for different B. pertussis populations. This study forms a baseline for future studies on the effect of vaccination programmes on B. pertussis populations.
- MeSH
- Antigens, Bacterial genetics MeSH
- Bordetella pertussis genetics isolation & purification classification MeSH
- Genetic Variation * MeSH
- Humans MeSH
- Minisatellite Repeats MeSH
- Molecular Epidemiology MeSH
- Multilocus Sequence Typing MeSH
- Whooping Cough * epidemiology microbiology MeSH
- Pertussis Toxin genetics MeSH
- Promoter Regions, Genetic MeSH
- Electrophoresis, Gel, Pulsed-Field MeSH
- Serotyping MeSH
- Check Tag
- Humans MeSH
- Geographicals
- Europe MeSH
