Impact of Microbiota on Resistance to Ocular Pseudomonas aeruginosa-Induced Keratitis.

Published online

Journal Article

The existence of the ocular microbiota has been reported but functional analyses to evaluate its significance in regulating ocular immunity are currently lacking. We compared the relative contribution of eye and gut commensals in regulating the ocular susceptibility to Pseudomonas aeruginosa-induced keratitis. We find that in health, the presence of microbiota strengthened the ocular innate immune barrier by significantly increasing the concentrations of immune effectors in the tear film, including secretory IgA and complement proteins. Consistent with this view, Swiss Webster (SW) mice that are typically resistant to P. aeruginosa-induced keratitis become susceptible due to the lack of microbiota. This was exemplified by increased corneal bacterial burden and elevated pathology of the germ free (GF) mice when compared to the conventionally maintained SW mice. The protective immunity was found to be dependent on both eye and gut microbiota with the eye microbiota having a moderate, but significant impact on the resistance to infection. These events were IL-1ß-dependent as corneal IL-1ß levels were decreased in the infected GF and antibiotic-treated mice when compared to the SPF controls, and neutralization of IL-1ß increased the ocular bacterial burden in the SPF mice. Monocolonizing GF mice with Coagulase Negative Staphylococcus sp. isolated from the conjunctival swabs was sufficient to restore resistance to infection. Cumulatively, these data underline a previously unappreciated role for microbiota in regulating susceptibility to ocular keratitis. We predict that these results will have significant implications for contact lens wearers, where alterations in the ocular commensal communities may render the ocular surface vulnerable to infections.

Full Text

Duke Authors

Cited Authors

  • Kugadas, A; Christiansen, SH; Sankaranarayanan, S; Surana, NK; Gauguet, S; Kunz, R; Fichorova, R; Vorup-Jensen, T; Gadjeva, M

Published Date

  • September 2016

Published In

Volume / Issue

  • 12 / 9

Start / End Page

  • e1005855 -

PubMed ID

  • 27658245

Pubmed Central ID

  • 27658245

Electronic International Standard Serial Number (EISSN)

  • 1553-7374

Digital Object Identifier (DOI)

  • 10.1371/journal.ppat.1005855

Language

  • eng

Conference Location

  • United States