SUMMARY Alpha herpesviruses are a subfamily of ubiquitous viruses that can cause a spectrum of clinically-significant diseases including blindness from acute retinal necrosis (ARN). Unfortunately, even with timely antiviral treatment, irreversible pathological changes occur within the retina and significantly increase the risk of vision- threatening complications to further compromise an already poor visual prognosis. Since the advent of acyclovir, there have been no major advances in the treatment of clinically-significant herpes infections despite the vision-degrading complications and very little is known in regards to the immune response to the virus within the retina. This proposal will provide a fundamental understanding of the innate immune response to HSV-1 within the retina, while developing critical skills in career development. The long-term goal of this project is to acquire the scientific skills needed to enhance our understanding and pursue novel therapies to preserve vision and reduce complications related to ARN as an independent clinician-scientist. The scientific objective of this K08 proposal is to test the hypothesis that type I interferons (IFNs) are central to host defense to viral infection of the retina and that toll-like receptor-3 within retinal microglia activate this innate immune response. We propose evaluating the innate immune response to herpes virus infections of the retina by utilizing several immune knock-out mouse lines, human retinal cell cultures, and vitreous specimens from patients with ARN to assess the role of IFNs and their role in neuroinflammation. Three focused specific aims will be utilized to test our hypothesis: 1) Identify pathways and cell types responsible for HSV innate immunity within the retina; 2) Determine the role of downstream IFNs in host defense against viral infection of the retina; 3) Identify the predominate IFN subtype and cellular source in acute retinal necrosis from human samples. The career development objective is to develop the mentorship and expertise needed to become a productive and independent clinician-scientist. The Department of Ophthalmology and Visual Sciences and the University of Nebraska Medical Center have state-of-the-art laboratory facilities and world-class faculty with expertise in neuroimmunology, viral infections, and innate immune signaling to serve as the mentoring team. The institutional resources, mentorship team, and career development plan have been developed to specifically promote scientific independence in the study of neuroinflammation of the retina.