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-1[alpha] (IL-1[alpha]), interleukin-1[beta] (IL-1[beta]) and tumour necrosis factor [alpha] (TNF[alpha]), 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-1[alpha], IL-1[beta], IL-6, TNF[alpha] and VEGF.Conclusions: Porcine vitreous-derived cells are stimulated by IL-1[alpha], IL-1[beta] and TNF[alpha], 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.