%0 Journal Article %A Humphreys, Gavin J. %A Kumar, Nirmal %A McBain, Andrew J. %T Low incidence of coaggregation amongst bacteria isolated from the upper respiratory tract in health and disease %D 2017 %J Journal of Medical Microbiology, %V 66 %N 9 %P 1338-1341 %@ 1473-5644 %R https://doi.org/10.1099/jmm.0.000567 %K antagonism %K nasal microbiota %K chronic rhinosinusitis %I Microbiology Society, %X The nasal cavity harbours a commensal microbiota that reportedly provides colonization resistance against respiratory pathogens. Following the onset of chronic rhinosinusitis (CRS), a change in sinus microbiota composition is frequently reported in which atypical anaerobic and/or Gram-negative bacteria predominate. We have investigated pairwise interactions between respiratory bacteria isolated from healthy adults (n=3) and individuals exhibiting CRS (n=3). Antagonism was determined using a spot plate methodology and coaggregation scores were determined using a quantitative spectrophotometric assay. Obligate anaerobes were isolated from all CRS samples and exhibited inter-host growth inhibition of commensal nasal bacteria, including Corynebacterium spp. and Staphylococcus spp. Antagonism between bacteria isolated from healthy individuals was limited to corynebacterial-mediated inhibition of the staphylococci. The frequency of coaggregation was low overall (2/153 pairwise interactions). Antagonism of the nasal microbiota by respiratory pathogens may represent a competitive strategy in the sinus and warrants further investigation. %U https://www.microbiologyresearch.org/content/journal/jmm/10.1099/jmm.0.000567