Fig. 8

Retina–bone-marrow–blood–retina pathway of fibrocytes and macrophage recruitment in the development of subretinal fibrosis. Retinal injury is detected by the bone marrow, which then produces fibrocytes and pro-fibrotic macrophages and releases them to the blood circulation. Once recruited into the damaged site, fibrocytes can differentiate into myofibroblasts. Macrophages can release profibrotic factors that promote epithelial-to-mesenchymal transition (EMT) in RPE cells. Macrophages can also participate in subretinal fibrosis through macrophage-to-myofibroblast transition (MMT). This process is augmented during ageing. (Image was created in BioRender.com)