Association of Choroidal Interleukin-17-Producing T Lymphocytes and Macrophages with Geographic Atrophy

Purpose: To evaluate the presence of interleukin-17 (IL-17)-producing cells in patients with geographic atrophy (GA). Methods: In this short report, we analyzed IL-17, CD3, and IBA-1 expression by immunohistochemistry on paraffin-embedded sections from 13 donors with a known history of GA, confirmed by fundus appearance and histology, and 7 age-matched control donors. Results/Conclusion: We showed that IL-17 + cells are found near areas of retinal pigmented epithelium atrophy in the eyes of GA patients. IL-17 + cells mainly localized to CD3 + cells, which identifies T lymphocytes, as well as IBA-1 + cells, which identifies mononuclear phagocytes. Therefore, IL-17 could be involved in the pathological mechanisms that contribute to the degeneration observed in GA.