advertisement
Abstract #46861 Published in IGR 13-3
Alterations in the aqueous humor proteome in patients with a glaucoma shunt device
Anshu A; Price MO; Richardson MR; Segu ZM; Lai X; Yoder MC; Price FWMolecular Vision 2011; 17: 1891-1900
See also comment(s) by Sanjoy Bhattacharya •
Purpose: To investigate whether implantation of a glaucoma shunt device leads to inappropriate accumulation of plasma derived proteins in the aqueous humor. Methods: Aqueous humor samples were collected from 11 patients (study group) with a glaucoma shunt device undergoing either cataract surgery or a corneal transplant and 11 patients (control) with senile cataract undergoing routine cataract extraction. Of the study group, 9 had an Ahmed valve implant and 2 eyes had a Baerveldt implant. Tryptic digests of the mixture of proteins in aqueous humor (AH) were analyzed using Liquid Chromatography/Mass Spectrometry (LCMS/ MS). Proteins were identified with high confidence using stringent criteria and compared quantitatively using a labelfree platform (IdentiQuantXL(TM)). Results: We identified 135 proteins in the albumin-depleted fraction in both the study and control group AH. Using stringent criteria, 13 proteins were detected at a significantly higher level compared to controls. These proteins are known to play a role in oxidative stress, apoptosis, inflammation and/or immunity and include gelsolin (p=0.00005), plasminogen (p=0.00009), angiotensinogen (p=0.0001), apolipoprotein A-II (p=0.0002), beta-2-microglobulin (p=0.0002), dickkopf-3 (DKK-3; p=0.0002), pigment epithelium-derived factor (p=0.0002), RIG-like 7-1 (p=0.0002), afamin (p=0.0003), fibronectin 1 (FN1; p=0.0003), apolipoprotein A-I (p=0.0004), activated complement C4 protein (C4a; p=0.0004) and prothrombin (p=0.0004). Many of the identified proteins were novel proteins that have not been associated with glaucoma in prior studies. All but C4a (complement C4 is a plasma protein but not in an activated form) are known plasma proteins and the elevated levels of these proteins in the aqueous humor suggests a breach in the blood-aqueous barrier with passive influx into the anterior chamber of the eye. Conclusions: The presence of these proteins in the aqueous humor suggests that glaucoma shunt device causes either a breach in blood-aqueous barrier or chronic trauma, increasing influx of oxidative, apoptotic and inflammatory proteins that could potentially cause corneal endothelial damage.
M. O. Price. Cornea Research Foundation of America, 9002 North Meridian Street, Suite 212, Indianapolis, IN, United States.
Classification:
3.12 Proteomics (Part of: 3 Laboratory methods)
2.6.3 Compostion (Part of: 2 Anatomical structures in glaucoma > 2.6 Aqueous humor dynamics)
12.8.2 With tube implant or other drainage devices (Part of: 12 Surgical treatment > 12.8 Filtering surgery)
