Anti-EF-Tu IgG titers increase with age and may contribute to protection against the respiratory pathogen Haemophilus influenzae

Authors

Oskar Thofte, Clinical Microbiology, Department of Translational Medicine, Faculty of Medicine, Lund University, Malmö, Sweden.
Ravinder Kaur, Rochester Regional HealthFollow
Yu-Ching Su, Clinical Microbiology, Department of Translational Medicine, Faculty of Medicine, Lund University, Malmö, Sweden.
Marta Brant, Clinical Microbiology, Department of Translational Medicine, Faculty of Medicine, Lund University, Malmö, Sweden.
Anna Rudin, Department of Immunology, Sahlgrenska University Hospital, University of Gothenburg, Gothenburg, Sweden.
Derek Hood, Mammalian Genetics Unit, MRC Harwell Institute, Harwell Science & Innovation Campus, Oxfordshire, UK.
Kristian Riesbeck, Clinical Microbiology, Department of Translational Medicine, Faculty of Medicine, Lund University, Malmö, Sweden.

Department

Research

Document Type

Article

Publication Title

European Journal Of Immunology

Abstract

Non-typeable Haemophilus influenzae (NTHi) is a pathogen that commonly colonizes the nasopharynx of preschool children, causing opportunistic infections including acute otitis media (AOM). Patients suffering from chronic obstructive pulmonary disease (COPD) are persistently colonized with NTHi and occasionally suffer from exacerbations by the bacterium leading to increased morbidity. Elongation-factor thermo unstable (EF-Tu), a protein critical for bacterial protein synthesis, has been found to moonlight on the surface of several bacteria. Here, we show that antibodies against NTHi EF-Tu were present in children already at 18 months of age, and that the IgG antibody titers increased with age. Children harboring NTHi in the nasopharynx also displayed significantly higher IgG concentrations. Interestingly, children suffering from AOM had significantly higher anti-EF-Tu IgG levels when NTHi was the causative agent. Human sera recognized mainly the central and C-terminal part of the EF-Tu molecule and peptide-based epitope mapping confirmed similar binding patterns for sera from humans and immunized mice. Immunization of BALB/c and otitis-prone Junbo (C3H/HeH) mice promoted lower infection rates in the nasopharynx and middle ear, respectively. In conclusion, our results suggest that IgG directed against NTHi EF-Tu may play an important role in the host immune response against NTHi.

First Page

490

Last Page

499

DOI

10.1002/eji.201847871

Volume

49

Issue

3

Publication Date

3-1-2019

Medical Subject Headings

Adult; Age Factors; Animals; Antibodies, Bacterial (administration & dosage, immunology, metabolism); Child; Child, Preschool; Haemophilus Infections (immunology, microbiology, prevention & control); Haemophilus influenzae (drug effects, immunology, physiology); Humans; Immunization; Immunoglobulin G (administration & dosage, immunology, metabolism); Infant; Mice, Inbred BALB C; Mice, Inbred C3H; Mice, Inbred C57BL; Otitis Media (immunology, microbiology); Peptide Elongation Factor Tu (immunology, metabolism); Respiratory System (drug effects, immunology, microbiology)

PubMed ID

30566236

Recommended Citation

Thofte, O., Kaur, R., Su, Y., Brant, M., Rudin, A., Hood, D., & Riesbeck, K. (2019). Anti-EF-Tu IgG titers increase with age and may contribute to protection against the respiratory pathogen Haemophilus influenzae. European Journal Of Immunology, 49 (3), 490-499. https://doi.org/10.1002/eji.201847871