Original ContributionNrf2 is a critical modulator of the innate immune response in a model of uveitis
Section snippets
Mice
Nrf2-deficient (Nrf2−/−) mice were generated as described [14] and backcrossed into the C57BL6 background. Wild-type (Nrf2+/+) and Nrf2−/− mice were fed an AIN-76A diet and water ad libitum and were housed under controlled conditions (25 °C, 12-h light–dark cycles). All experimental protocols were performed in accordance with National Institutes of Health (NIH) guidelines and were approved by the Johns Hopkins University Animal Care and Use Committee.
Treatment
Mice received a single intraperitoneal
Retinal and ciliary body ROS are increased in Nrf2-deficient mice given an LPS challenge
Using DHE histochemical staining for ROS, Fig. 1A shows that the neurosensory retinas of Nrf2+/+ and Nrf2−/− mice have a low level of detectable ROS at baseline. After LPS stimulation, the degree of detectable ROS increased dramatically in all layers of the neurosensory retina. Interestingly, the retinal pigmented epithelium, which has a robust antioxidant capability, shows little increase in ROS. The increase in ROS was significantly greater in Nrf2−/− than in Nrf2+/+ mice stimulated with LPS (
Discussion
In this study, we demonstrate that Nrf2 is a critical host factor in modulating the innate immune response to LPS stimulation in a murine model of uveitis. LPS increased ROS, disrupted the coordinated Nrf2-mediated antioxidant gene expression response, induced a cluster of inflammatory mediators in the neurosensory retina, and finally, enhanced leukocyte adhesion to the retinal vascular endothelium. Although we focused our studies on the retina, we found a similar response in the ciliary body.
Acknowledgments
This work is supported by Grant EY14005 (J.T.H.) and The Robert Bond Welch Professorship (J.T.H.); a Bausch and Laumb Fellowship Award (N.N.), the Keio University Medical Science Fund (N.N.), and The Uehara Memorial Foundation (N.N.); NIH HL081205 (S.B.), NIH/NHLBI SCCOR Grant P50HL084945 (S.B.), and a Clinical Innovator Award from FAMRI (S.B.); NIH Grant CA-78814 (M.S.) and a grant from Reata Pharmaceuticals (M.S.); and generous gifts from Ric and Sandy Forsythe, the Kwok family, the Merlau
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