title: A rapid ELISA-based method for screening Bordetella pertussis strain production of antigens included in current acellular pertussis vaccines.
abstract: BACKGROUND
  Despite extensive vaccinations, there have been pertussis epidemics in many countries including the Netherlands, the UK, Australia and the USA. During these epidemics Bordetella pertussis strains not producing the vaccine antigen pertactin (Prn) are emerging and increasing in numbers. However, methods for confirming PRN production of B. pertussis isolates are combined PCR or PCR-based sequencing tests and western blotting. Furthermore, data about production of pertussis toxin (PT) and filamentous hemagglutinin (FHA) of these isolates are scarce. Fimbriae (Fim) production is usually determined by agglutination and reported as serotype. In this study we developed an easy, accurate and rapid method for screening PT and FHA production. Methods for Prn and Fim production have been published earlier.
  
  
  METHODS
  We analyzed altogether 109 B. pertussis strains, including 103 Finnish B. pertussis strains collected during 2006-2013, international strain Tohama I, French strains FR3496 (PT-negative), FR3693 (Prn-negative) and FR4624 (FHA-negative) and Fim-serotype reference strains S1 (producing only Fim2) and S3 (producing only Fim3). An indirect ELISA with whole bacterial cells as coating antigen was developed and used for rapid screening of the B. pertussis strains. Production of different antigens (PT, FHA, Prn, Fim2 and Fim3) was detected with specific monoclonal antibodies (mAbs).
  
  
  RESULTS
  From the 103 Finnish B. pertussis strains tested, all were positive for PT, FHA and Fim. Four were found negative for Prn, and they were isolated during 2011-2013.
  
  
  CONCLUSIONS
  The newly developed method proved to be useful and simple for rapid screening of different antigen production of B. pertussis isolates.
authors.affiliation: Department of Infectious Disease Surveillance and Control, National Institute for Health and Welfare, Turku, Finland.
authors.forename: Alex-Mikael
authors.initials: AM
authors.lastname: Barkoff
authors.affiliation: National Centre of Reference of Whooping Cough and Other Bordetelloses, Pasteur Institute, Paris, France.
authors.forename: Nicole
authors.initials: N
authors.lastname: Guiso
authors.affiliation: National Centre of Reference of Whooping Cough and Other Bordetelloses, Pasteur Institute, Paris, France.
authors.forename: Sophie
authors.initials: S
authors.lastname: Guillot
authors.affiliation: National Institute for Biological Standards and Control, Potters Bar, Hertfordshire EN6 3QG, UK.
authors.forename: Dorothy
authors.initials: D
authors.lastname: Xing
authors.affiliation: National Institute for Biological Standards and Control, Potters Bar, Hertfordshire EN6 3QG, UK.
authors.forename: Kevin
authors.initials: K
authors.lastname: Markey
authors.affiliation: Laboratory for Infectious Diseases and Screening (LIS), Netherlands Centre for Infectious Diseases Control, National Institute for Public Health and the Environment (RIVM), Bilthoven, Netherlands.
authors.forename: Guy
authors.initials: G
authors.lastname: Berbers
authors.affiliation: Department of Pediatrics, Turku University Hospital, Turku, Finland.
authors.forename: Jussi
authors.initials: J
authors.lastname: Mertsola
authors.affiliation: Department of Infectious Disease Surveillance and Control, National Institute for Health and Welfare, Turku, Finland. Electronic address: Qiushui.He@thl.fi.
authors.forename: Qiushui
authors.initials: Q
authors.lastname: He
mesh_terms: D018829:Adhesins, Bacterial / Q000276:immunology*; D000818:Animals; D000911:Antibodies, Monoclonal; D000942:Antigens, Bacterial / Q000276:immunology*; D001425:Bacterial Outer Membrane Proteins / Q000276:immunology*; D001886:Bordetella pertussis / Q000145:classification / Q000276:immunology*; D004797:Enzyme-Linked Immunosorbent Assay; D010567:Pertussis Vaccine / Q000276:immunology*; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D013997:Time Factors; D014611:Vaccination; D022282:Vaccines, Acellular / Q000276:immunology; D010566:Virulence Factors, Bordetella / Q000276:immunology*
chemical_list: D018829:Adhesins, Bacterial; D000911:Antibodies, Monoclonal; D000942:Antigens, Bacterial; D001425:Bacterial Outer Membrane Proteins; D010567:Pertussis Vaccine; D022282:Vaccines, Acellular; D010566:Virulence Factors, Bordetella; C065273:filamentous hemagglutinin adhesin, Bordetella pertussis; C068929:pertactin
keywords: Antigen production; Bordetella pertussis; ELISA; Pertactin; Pertussis