Interactions between vitreous‐derived cells and vascular endothelial cells in vitreoretinal diseases

Purpose: This study aimed to investigate the roles played by vitreous‐derived cells in the pathogenesis of vitreoretinal vascular diseases. Methods: The vitreous was removed from porcine eyes and small pieces were cultured from which vitreous‐derived cells were isolated. Polymerase chain reaction and ELISA were performed to determine the expression of vascular endothelial growth factor (VEGF) and interleukin 6 (IL‐6) at the mRNA and protein levels, respectively. The viability of human retinal endothelial cells (HRECs) exposed to vitreous‐derived cells was assessed by MTT assay. Results: Expression of the mRNA and protein of VEGF and IL‐6 was increased by exposing the porcine vitreous‐derived cells (PVDCs) to interleukin‐1α (IL‐1α), interleukin‐1β (IL‐1β) and tumour necrosis factor α (TNFα), but not to VEGF or IL‐6. The percentage of living human vascular endothelial cells was increased by including VEGF and IL‐6 in the culture media. The viability of HRECs was affected by co‐culturing them with PVDCs that had been exposed to IL‐1α, IL‐1β, IL‐6, TNFα and VEGF. Conclusions: Porcine vitreous‐derived cells are stimulated by IL‐1α, IL‐1β and TNFα, and produce VEGF and IL‐6, which then enhance the proliferation of vascular endothelial cells. This network, including the cytokines and different types of cells, may contribute to the pathogenesis of proliferative vitreoretinal diseases.