[HTML][HTML] IL-10 indirectly regulates corneal lymphangiogenesis and resolution of inflammation via macrophages

D Hos, F Bucher, B Regenfuss, ML Dreisow… - The American journal of …, 2016 - Elsevier
D Hos, F Bucher, B Regenfuss, ML Dreisow, F Bock, LM Heindl, SA Eming, C Cursiefen
The American journal of pathology, 2016Elsevier
The role of IL-10, a primarily anti-inflammatory cytokine, in the regulation of inflammatory
lymphangiogenesis is undetermined. Herein, we show that IL-10 modulates corneal
lymphangiogenesis and resolution of inflammation. IL-10 was not expressed in healthy
corneas but was up-regulated in inflamed corneas by infiltrating macrophages.
Macrophages up-regulated the expression of prolymphangiogenic vascular endothelial
growth factor-C upon stimulation with IL-10. Consistently, corneal inflammation resulted in …
The role of IL-10, a primarily anti-inflammatory cytokine, in the regulation of inflammatory lymphangiogenesis is undetermined. Herein, we show that IL-10 modulates corneal lymphangiogenesis and resolution of inflammation. IL-10 was not expressed in healthy corneas but was up-regulated in inflamed corneas by infiltrating macrophages. Macrophages up-regulated the expression of prolymphangiogenic vascular endothelial growth factor-C upon stimulation with IL-10. Consistently, corneal inflammation resulted in reduced expression of vascular endothelial growth factor-C and decreased corneal lymphangiogenesis in IL-10–deficient mice (IL-10−/−). The effect of IL-10 on lymphangiogenesis was indirect via macrophages, because IL-10 did not directly affect lymphatic endothelial cells. The expression of proinflammatory cytokines and the numbers of infiltrating macrophages increased and remained elevated in inflamed corneas of IL-10−/− mice, indicating that IL-10 deficiency led to more severe and prolonged inflammation. The corneal phenotype of IL-10 deficient mice was mimicked in mice with conditional deletion of Stat3 in myeloid cells (lysozyme M Cre mice Stat3fl/fl mice), corroborating the critical role of macrophages in the regulation of lymphangiogenesis. Furthermore, local treatment with IL-10 promoted lymphangiogenesis and faster egress of macrophages from inflamed corneas. Taken together, we demonstrate that IL-10 indirectly regulates inflammatory corneal lymphangiogenesis via macrophages. Reduced lymphangiogenesis in IL-10−/− and lysozyme M Cre Stat3fl/fl mice is associated with more severe inflammatory responses, whereas IL-10 treatment results in faster resolution of inflammation. IL-10 might be used therapeutically to terminate pathological inflammation.
Elsevier