The protein/peptide patterns in the aqueous humour of primary open-angle glaucoma (POAG) subjects differs significantly from that of control subjects, according to a study published in the August 2008 issue of Molecular Vision.

Dr F. H. Grus of the Department of Ophthalmology, Johannes Gutenberg University, Mainz, Germany and colleagues conducted protein profiling on the aqueous humour of POAG patients (n=52) and a control group (n=55) using two methods: surface enhanced laser desorption/ionization-time of flight-mass spectrometry (SELDI-TOF-MS) ProteinChip arrays (POAG, n=22; control, n=24) and two-dimensional electrophoresis (POAG, n=30; control, n=31). The team detected and compared the protein spots of all groups.

Researchers identified 250 protein peaks in the SELDI-TOF-MS samples, and 177 complex protein patterns in the two-dimensional electrophoresis samples. An upregulated biomarker that was identified in the glaucomatous samples, regardless of the testing method, was transthyretin.

The researchers concluded that significantly higher levels of transthyretin were present in the aqueous of glaucomatous subjects than in non-glaucomatous subjects, and that this protein, which has previously been shown to form amyloid deposits, could play a role in the pathogenesis of glaucoma.