Antibacterial antibody responses associated with the development of asthma in house dust mite-sensitised and non-sensitised children
- Belinda J Hales1,
- Lee Ying Chai1,
- Claire E Elliot1,
- Leigh J Pearce1,
- Guicheng Zhang1,
- Tatjana K Heinrich1,
- Wendy-Anne Smith1,
- Merci M Kusel1,
- Patrick G Holt1,
- Peter D Sly2,
- Wayne R Thomas1
- 1Telethon Institute for Child Health Research and Centre for Child Health Research, University of Western Australia, Subiaco, Western Australia, Australia
- 2Queensland Children's Medical Research Institute, The University of Queensland, Royal Children's Hospital, Herston, Queensland, Australia
- Correspondence to Dr B J Hales, Telethon Institute for Child Health Research and Centre for Child Health Research, University of Western Australia, 100 Roberts Road, Subiaco, WA 6008, Australia;
Contributors BJH and WRT were responsible for the conception and design of the study and for writing the manuscript. BJH performed the majority of the data analysis, aided by LYC, CEE and LJP. GZ provided expert statistical advice and assisted with the data analysis. BJH, TKH, W-AS and WRT were responsible for the design and validation of the conserved protein antigens used in the study. MMHK, PDS and PGH assisted in interpretation of the analysis and were involved in advice and feedback of the manuscript. All authors gave final approval of the version to be published.
- Received 26 June 2011
- Accepted 28 October 2011
- Published Online First 21 November 2011
Background Infants who develop house dust mite (HDM) allergy and HDM-sensitised children with severe persistent asthma have low antibody responses to the P6 antigen of Haemophilus influenzae.
Objective To measure the development of antibody to two ubiquitous bacteria of the respiratory mucosa in a prospective birth cohort at high risk of allergic disease and to assess which responses are associated with asthma and atopy.
Methods IgG1 and IgG4 antibody to H influenzae (P4 and P6) and Streptoccocus pneumoniae (PspA and PspC) surface antigens was measured in yearly blood samples of children aged 1–5 years. IgE to the P6 antigen was examined for the 5-year group. The children were stratified based on HDM sensitisation and asthma at 5 years of age.
Results HDM-sensitised children had lower IgG1 antibody titres to the bacterial antigens, and early responses (<3 years and before the development of HDM sensitisation and asthma) corrected for multiple antigens were significantly reduced for P4, P6 and PspC (p=0.008, p=0.004 and p=0.028, respectively). Similar associations with asthma were also found (p=0.008, p=0.004 and p=0.032 for P4, P6 and PspC, respectively). The IgG4 antibody titre and prevalence were similar in both HDM-sensitised and non-sensitised groups, but sensitised children had a slower downregulation of the IgG4 response. Children with asthma (27/145 at 5 years) had lower anti-P6 IgE responses (p<0.05).
Conclusions HDM-sensitised children have early defective antibody responses to bacteria that are associated with asthma. Surprisingly, antibacterial IgE was associated with a reduced risk for asthma.
- asthma: IgG
- allergic lung disease
- bacterial infection
- lymphocyte biology
- viral infection
- asthma epidemiology
- asthma genetics
- respiratory infection
- asthma in primary care
- clinical epidemiology
- complementary medicine
- cystic fibrosis
- paediatric asthma
- respiratory measurement
Funding This work was supported by the National Health and Medical Research Council of Australia.
Competing interests None.
Ethics approval Ethics approval was provided by the Princess Margaret Hospital human ethics committee.
Provenance and peer review Not commissioned; externally peer reviewed.