Association of choroidal IL-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 and conclusion: we show that IL-17+ cells are found near areas of retinal pigmented epithelium (RPE) atrophy in 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 degeneration observed in GA.