Better colonisation of newly emerged Bordetella pertussis in the co-infection mouse model study

Azadeh Safarchi; Sophie Octavia; Laurence Don Wai Luu; Chin Yen Tay; Vitali Sintchenko; Nicholas Wood; Helen Marshall; Peter McIntyre; Ruiting Lan

doi:10.1016/j.vaccine.2016.06.052

Better colonisation of newly emerged Bordetella pertussis in the co-infection mouse model study

Vaccine. 2016 Jul 25;34(34):3967-71. doi: 10.1016/j.vaccine.2016.06.052. Epub 2016 Jun 23.

Authors

Azadeh Safarchi¹, Sophie Octavia¹, Laurence Don Wai Luu¹, Chin Yen Tay², Vitali Sintchenko³, Nicholas Wood⁴, Helen Marshall⁵, Peter McIntyre⁴, Ruiting Lan⁶

Affiliations

¹ School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, New South Wales, Australia.
² Pathology and Laboratory Medicine, University of Western Australia, Perth, Western Australia, Australia.
³ Centre for Infectious Diseases and Microbiology-Public Health, Institute of Clinical Pathology and Medical Research - Pathology West, Westmead Hospital, New South Wales, Australia; Marie Bashir Institute for Infectious Diseases and Biosecurity, Sydney Medical School, University of Sydney, New South Wales, Australia.
⁴ National Centre for Immunisation Research and Surveillance, Children's Hospital at Westmead, New South Wales, Australia.
⁵ Vaccinology and Immunology Research Trials Unit, Women's and Children's Hospital and School of Paediatrics and Reproductive Health and Robinson Research Institute, University of Adelaide, South Australia, Australia.
⁶ School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, New South Wales, Australia. Electronic address: r.lan@unsw.edu.au.

PMID: 27346304
DOI: 10.1016/j.vaccine.2016.06.052

Abstract

Molecular epidemiological data indicates that the resurgence of pertussis (whooping cough) in populations with high vaccine coverage is associated with genomic adaptation of Bordetella pertussis, the causative agent of the disease, to vaccine selection pressure. We have previously shown that in the period after the introduction of acellular pertussis vaccine (ACV), the majority of circulating strains in Australia switched to single nucleotide polymorphism (SNP) cluster I (carrying ptxP3/prn2), replacing SNP cluster II (carrying ptxP1/prn3). In this study, we carried out an in vivo competition assay using a mouse model infected with SNP cluster I and II B. pertussis strains from Australia. We found that the SNP cluster I strain colonised better than the SNP cluster II strain, in both naïve and immunised mice, suggesting that SNP cluster I strains had better fitness regardless of immunisation status of the host, consistent with SNP cluster I strains replacing SNP cluster II. Nevertheless, we found that ACV enhanced clearance of both SNP cluster I and II strains from the mouse respiratory tract.

Keywords: Acellular pertussis vaccine; Bordetella pertussis; Fitness; Mouse model infection; SNP cluster I; ptxP3 strain.

MeSH terms

Animals
Australia
Bordetella pertussis / genetics*
Coinfection / microbiology
Disease Models, Animal
Evolution, Molecular*
Female
Genetic Fitness*
Mice
Mice, Inbred BALB C
Pertussis Vaccine / administration & dosage
Polymorphism, Single Nucleotide
Respiratory System / microbiology
Selection, Genetic
Whooping Cough / microbiology*
Whooping Cough / prevention & control

Substances

Pertussis Vaccine