Kininogen 1 and insulin‐like growth factor binding protein 6: candidate serum biomarkers of proliferative vitreoretinopathy

Abstract

BackgroundThe aim was to validate whether kininogen 1 (KNG1) or insulin‐like growth factor binding protein 6 (IGFBP‐6) are serum biomarkers of proliferative vitreoretinopathy (PVR).MethodsSamples from vitreous and corresponding serum samples were collected from patients with PVR. The donor vitreous samples and serum samples from healthy volunteers and volunteers who had undergone vitrectomies for other conditions were used as controls. The samples were subsequently analysed using Western blotting (WB) and enzyme‐linked immunosorbent assay.ResultsThe Western blotting outcomes indicated both IGFBP‐6 and KNG1 could be specifically detected in the vitreous and serum samples of patients with PVR. The concentrations of KNG1 and IGFBP‐6 were significantly higher in both vitreous and serum samples from patients with severe PVR than in the samples from patients with moderate PVR. The serum concentrations of KNG1 or IGFBP‐6 had decreased by the post‐vitrectomy examinations. The receiver operating characteristic (ROC) analyses when the concentrations of IGFBP‐6 or KNG1 were greater than 181.4-pg/ml or 441.75-ng/ml, respectively, predicted severe PVR with both a sensitivity and specificity of over 70 per cent. When the concentrations of IGFBP‐6 or KNG1 were greater than 98.5-pg/ml or 88.5-ng/ml, respectively, they predicted the PVR prognosis with both a sensitivity and specificity of 80 per cent.ConclusionsKNG1 and IGFBP‐6 may be candidate serum biomarkers of PVR.