Abstract
Purpose: :
We have recently reported that kininogen is a potential biomarker for proliferative vitreoretinopathy (PVR) (Yu et al 2008). In this study, we quantitatively evaluated the predictive potential of kininogen and insulin-like growth factor binding protein-6 (IGFBP-6) for severe PVR.
Methods: :
Vitreous and serum samples were obtained from 24 PVR patients. Patients who underwent vitrectomy with silicone tamponade (n=8) and patients who experienced recurrent retinal detachment after scleral buckling surgery (n=8) were recruited for serum tests as well. Vitreous from 8 donated normal eyes, and serum samples from 20 healthy volunteers served as control. Western blot analysis was employed to detect the presence of kininogen and IGFBP-6. The protein concentration was measured by using ELISA analysis.
Results: :
Although IGFBP-6 was absent in 2 PVR vitreous, both kininogen and IGFBP-6 were otherwise found in all PVR vitreous and serum samples. Neither kininogen nor IGFBP-6 can be detected in normal vitreous or serum samples. Protein expression was more intensive in severe PVR vitreous than in mild PVR vitreous, which was confirmed by a significantly higher concentration of each protein in sever PVR vitreous (table 1). Kininogen was about 2 times higher in serum than in vitreous; whereas IGFBP-6 was much lower in serum than in vitreous. Serum level of both proteins dropped significantly 6 months after PVR surgery, to a comparable level of patients underwent either vitrectomy with silicone tamponade or scleral buckling surgery.
Conclusions: :
Kininogen and IGFBP-6 are presented in serum and vitreous in PVR patients. The strength of protein expression is related to the severity of PVR. These results suggested that kininogen and IGFBP-6 can be biomarkers for severe PVR.
Keywords: proliferative vitreoretinopathy • clinical (human) or epidemiologic studies: risk factor assessment