Inactivation of the miR-183/96/182 Cluster Decreases the Severity of Pseudomonas aeruginosa-Induced Keratitis.

Abstract

PURPOSE:

The microRNA-183/96/182 cluster (miR-183/96/182) plays important roles in sensory organs. Because the cornea is replete with sensory innervation, we hypothesized that miR-183/96/182 modulates the corneal response to bacterial infection through regulation of neuroimmune interactions.

METHODS:

Eight-week-old miR-183/96/182 knockout (ko) mice and their wild-type littermates (wt) were used. The central cornea of anesthetized mice was scarred and infected with Pseudomonas aeruginosa (PA), strain 19660. Corneal disease was graded at 1, 3, and 5 days postinfection (dpi). Corneal RNA was harvested for quantitative RT-PCR. Polymorphonuclear neutrophils (PMN) were enumerated by myeloperoxidase assays; the number of viable bacteria was determined by plate counts, and ELISA assays were performed to determine cytokine protein levels. A macrophage (Mϕ) cell line and elicited peritoneal PMN were used for in vitro functional assays.

RESULTS:

MicroRNA-183/96/182 is expressed in the cornea, and in Mϕ and PMN of both mice and humans. Inactivation of miR-183/96/182 resulted in decreased corneal nerve density compared with wt mice. Overexpression of miR-183/96/182 in Mϕ decreased, whereas knockdown or inactivation of miR-183/96/182 in Mϕ and PMN increased their capacity for phagocytosis and intracellular killing of PA. In PA-infected corneas, ko mice showed decreased proinflammatory neuropeptides such as substance P and chemoattractant molecules, MIP-2, MCP1, and ICAM1; decreased number of PMN at 1 and 5 dpi; increased viable bacterial load at 1 dpi, but decreased at 5 dpi; and markedly decreased corneal disease.

CONCLUSIONS:

MicroRNA-183/96/182 modulates the corneal response to bacterial infection through its regulation of corneal innervation and innate immunity.

• Authors: Chithra K Muraleedharan, Sharon A McClellan, Ronald P Barrett, Cui Li, Daniel Montenegro, Thomas Carion, Elizabeth Berger, Linda D Hazlett, Shunbin Xu
• Journal: Investigative ophthalmology & visual science (Invest Ophthalmol Vis Sci) Vol. 57 Issue 4 Pg. 1506-17 (Apr 2016) ISSN: 1552-5783 [Electronic] United States
• PMID: 27035623 (Publication Type: Journal Article, Research Support, N.I.H., Extramural, Research Support, Non-U.S. Gov't)

Chemical References

• Cytokines
• MicroRNAs
• Mirn182 microRNA, mouse
• Mirn183 microRNA, mouse
• Mirn96 microRNA, mouse

Topics

• Animals
• Cell Line
• Colony Count, Microbial
• Cornea (innervation, metabolism, microbiology)
• Corneal Ulcer (immunology, microbiology, prevention & control)
• Cytokines (metabolism)
• Enzyme-Linked Immunosorbent Assay
• Eye Infections, Bacterial (immunology, microbiology, prevention & control)
• Female
• Gene Silencing (physiology)
• Humans
• Immunity, Innate
• Macrophages (immunology)
• Male
• Mice
• Mice, Knockout
• MicroRNAs (genetics)
• Neutrophils (immunology)
• Pseudomonas Infections (immunology, microbiology, prevention & control)
• Pseudomonas aeruginosa (physiology)
• Real-Time Polymerase Chain Reaction
• Transfection
• Trigeminal Ganglion (immunology)