Effect of Photobiomodulation on Proliferative Changes in the Retina: Evidence from an In Vitro Model of PVR

We aimed to validate an in vitro model of proliferative vitreoretinopathy (PVR) and investigate the effect of 670 nm light photobiomodulation (PBM) on PVR pathophysiology.Immortalised retinal pigment epithelial cells (ARPE-19) were seeded at 3.0 × 10³ cells/well. Half were stimulated with TGF-β1 to induce EMT, then all cells were allocated to either PBM, one treatment of 670 nm light every 3 hours for 12 hours or control. EMT morphology was characterised by area, perimeter, perimeter-area ratio, maximum Feret diameter, minimum Feret diameter, Feret ratio, compactness, eccentricity, and radius. The same parameters were analysed to determine the effect of PBM on EMT morphology.TGF-β induced morphological changes in ARPE-19 consistent with EMT, namely increased eccentricity, compactness, maximum Feret diameter, Feret ratio and perimeter-area ratio. Treatment with 670 nm PBM mitigates changes in perimeter and maximum Feret diameter induced by EMT.The TGF-β1 stimulation of RPE cells produces a morphologically valid in vitro model of EMT. PBM is effective at mitigating some EMT-related morphological changes.