Characterising Clinical Staphylococcus Aureus Isolates from the Sinuses in Chronic Rhinosinusitis
Authors List
Wagner Mackenzie, B., Department of Surgery, The University of Auckland, Auckland, New Zealand
Zoing, M., Department of Surgery, The University of Auckland, Auckland, New Zealand
Radcliff, F.J., Department of Surgery, The University of Auckland, Auckland, New Zealand
Waite, D.W., School of Biological Sciences, The University of Auckland, Auckland, New Zealand
Taylor, M.W., School of Biological Sciences, The University of Auckland, Auckland, New Zealand
Biswas, K., Department of Surgery, The University of Auckland, Auckland, New Zealand
Douglas, R.G., Department of Surgery, The University of Auckland, Auckland, New Zealand.
Introduction: A clear role of Staphylococcus aureus in the pathogenesis of chronic rhinosinusitis (CRS) has not been demonstrated. We hypothesise that comparative analyses of S. aureus isolates from CRS with those from control participants will offer insight into the pathogenic link of this organism with disease.
Aims: The intra- and inter-subject S. aureus strain-level diversity in the sinuses of patients with and without CRS were compared. Bacterial community composition was investigated in subjects that cultured positive for S. aureus carriage. The responses of participant-derived S. aureus isolates to a commensal bacterium, Corynebacterium accolens, were compared to investigate underlying factors that may influence colonisation of this pathogen.
Methods: In this cross-sectional study, 100 patients (CRS = 64, control = 36) were screened for S. aureus carriage. Isolates were strain-typed using spa gene sequencing. The bacterial community composition of the sinus was assessed using 16S rRNA bacterial gene amplicon sequencing. S. aureus isolates cultured from patients with CRS where grown in co-culture with the commensal bacterium C. accolens and their growth rates characterised.
Results: The overall carriage prevalence of S. aureus in this cohort was 24% (CRS = 13%, control = 11%). All participants harboured one S. aureus strain and no trends in disease-specific strain-level diversity were observed. Bacterial community analyses revealed a negative association in the relative abundances of Staphylococcus and Corynebacteriumsequences. Co-cultivation experiments with S. aureus isolates and C. accolens reproduced this observation in in vitro.
Conclusions: We saw no significant associations of CRS disease with S. aureus strain types. The functional role that S. aureus occupies in CRS likely depends on other factors such as variations in gene expression and other members of the sinus bacterial community. Mechanisms underlying the antagonistic relationship between the pathobiont S. aureus and the commensal bacterium C. accolens should be explored further.
Wagner Mackenzie, B., Department of Surgery, The University of Auckland, Auckland, New Zealand
Zoing, M., Department of Surgery, The University of Auckland, Auckland, New Zealand
Radcliff, F.J., Department of Surgery, The University of Auckland, Auckland, New Zealand
Waite, D.W., School of Biological Sciences, The University of Auckland, Auckland, New Zealand
Taylor, M.W., School of Biological Sciences, The University of Auckland, Auckland, New Zealand
Biswas, K., Department of Surgery, The University of Auckland, Auckland, New Zealand
Douglas, R.G., Department of Surgery, The University of Auckland, Auckland, New Zealand.
Introduction: A clear role of Staphylococcus aureus in the pathogenesis of chronic rhinosinusitis (CRS) has not been demonstrated. We hypothesise that comparative analyses of S. aureus isolates from CRS with those from control participants will offer insight into the pathogenic link of this organism with disease.
Aims: The intra- and inter-subject S. aureus strain-level diversity in the sinuses of patients with and without CRS were compared. Bacterial community composition was investigated in subjects that cultured positive for S. aureus carriage. The responses of participant-derived S. aureus isolates to a commensal bacterium, Corynebacterium accolens, were compared to investigate underlying factors that may influence colonisation of this pathogen.
Methods: In this cross-sectional study, 100 patients (CRS = 64, control = 36) were screened for S. aureus carriage. Isolates were strain-typed using spa gene sequencing. The bacterial community composition of the sinus was assessed using 16S rRNA bacterial gene amplicon sequencing. S. aureus isolates cultured from patients with CRS where grown in co-culture with the commensal bacterium C. accolens and their growth rates characterised.
Results: The overall carriage prevalence of S. aureus in this cohort was 24% (CRS = 13%, control = 11%). All participants harboured one S. aureus strain and no trends in disease-specific strain-level diversity were observed. Bacterial community analyses revealed a negative association in the relative abundances of Staphylococcus and Corynebacteriumsequences. Co-cultivation experiments with S. aureus isolates and C. accolens reproduced this observation in in vitro.
Conclusions: We saw no significant associations of CRS disease with S. aureus strain types. The functional role that S. aureus occupies in CRS likely depends on other factors such as variations in gene expression and other members of the sinus bacterial community. Mechanisms underlying the antagonistic relationship between the pathobiont S. aureus and the commensal bacterium C. accolens should be explored further.
