Inhaltszusammenfassung

Glaucoma is a neurodegenerative eye disease manifested by the slow progressive loss of retinal ganglion cells (RGC) and their axons, leading to optic nerve damages and visual field defects. Although glaucoma is clinically well known for many years by now, the elevated intraocular pressure (IOP) remains the major risk factor for the development of glaucoma and IOP-lowering medications still represent the gold standard in glaucoma therapy. However, rather than preventing or even curing the neur...Glaucoma is a neurodegenerative eye disease manifested by the slow progressive loss of retinal ganglion cells (RGC) and their axons, leading to optic nerve damages and visual field defects. Although glaucoma is clinically well known for many years by now, the elevated intraocular pressure (IOP) remains the major risk factor for the development of glaucoma and IOP-lowering medications still represent the gold standard in glaucoma therapy. However, rather than preventing or even curing the neurological damages the current therapeutic approaches can just delay and slow down the disease progression. These circumstances emphasize the urgent need for the development of new diagnostic or therapeutic strategies in order to provide a personalized medical management for each glaucoma patient. The main objective of this doctoral thesis was to characterize the highly diverse antibody repertoire by liquid chromatography-mass spectrometry (LC-MS)-based quantitative proteomics and to identify new specific and sensitive biomarker candidates. As most important result, we identified 75 peptides of the variable IgG domain as potential biomarkers in primary-open angle glaucoma (POAG) patients. Moreover, we observed significant shifts in the variable heavy chain family distribution and disturbed κ/λ ratios in POAG patients strengthening the assumption of glaucoma-induced effects on the systemic humoral immune response. As second part of the project, we proved the neuroprotective potential of synthetic glaucoma associated complementarity-determining regions (CDR) on RGCs ex vivo. Particularly, the treatment with CDR1 peptide ASGYTFTNYGLSWVR resulted in about 30 % significant higher RGC survival rates which can possibly be traced back to the active inhibition or modulation of the molecular function of mitochondrial protein serine protease HTRA2. This specific peptide-protein interaction led to significant lesser cellular stress responses and increased activation of antioxidative signaling pathways in the CDR-treated retinal explants. As final part of this doctoral thesis, we compared the analytical performance of two solid phase extraction (SPE) methods for sample clean-up and peptide enrichment prior to LC MS analysis. The retinal proteome of the house swine (Sus scrofa domesticus) provides excellent requirements for this qualitative as well as quantitative MS-based comparison and delivered convincing results in terms of ocular proteomics. Both SPE systems worked equally well regarding sensitivity, reproducibility and protein/peptide recovery. But in terms of analysis speed and semi-automation, the centrifugal-based SPE technology (SOLAµTM HRP) clearly benefits compared to the pipette tip-based SPE method (ZIPTIP® C18). In conclusion, the present doctoral thesis provided deep and detailed insights into the complex autoimmune processes in the pathophysiology of glaucoma and emphasized synthetic CDR peptides as innovative new strategy in future glaucoma therapy. Moreover, the faster and more standardized analytical procedure for the LC-MS analysis will facilitate the management as well as coordination of high-throughput study designs and will significantly increase the quality of large-scale research projects in future.» weiterlesen» einklappen

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DDC Sachgruppe:
Biowissenschaften, Biologie