Objective:To identify and analyze proliferative diabetic retinopathy with heavy macular edema-related proteins in the vitreous. Mehtods:The vitreous samples of 27 eyes active proliferative diabetic retinopathy with heavy macular edema patients with 9 normal eyes vitreous samples were analyzed by two-dimensional gel electrophoresis then compared the 2-DE map with PDquest to find the disparation proteins spots.The spots were extracted and been enzymolysis and progressing mass spectrogram identification.Then according the results of Peptide Mass Finger printing(PMF)to find the disparation proteins by searching internet using Mascot and Ms-Fit.One sample of the each group was enrolled to identify disparation proteins by Western blot.Results:At least 30 proteins were up regulated or down-regulated by over two folds between two groups.20 protein spots up regulated and 10 down-regulated.Four proteins(apolipoprotein A-IV precursor

Transthyretin precursor

apolipoprotein D

Retinol-binding protein I

cellular)in the 20 spots were expressed significantly differently between the normal and PDR with heavy macular edema patients.The four proteins were up regulated in the diabetic retinopathy with macular edema patients.Conclusions:We constructed vitreous protein profiles for proliferative diabetic retinopathy with heavy macular edema patients and identified four candidate proteins believed to be involved in the pathogenesis of proliferative diabetic retinopathy with heavy macular edema.