A comparative study of immunodepletion and equalization methods for aortic stenosis human plasma.

Calcified aortic valve disease is a slowly progressive disorder that ranges from mild valve thickening with no obstruction of blood flow, known as aortic sclerosis, to severe calcification with impaired leaflet motion or aortic stenosis. Until now, aortic stenosis (AS) was thought to result from aging and "wear and tear" of the aortic valve, but nowadays, it is known that it presents the same risk factors as atherosclerosis and cardiovascular diseases.A proteomic analysis of plasma could permit to identify the changes in protein expression induced by AS in this biological sample. However, the characterization of human plasma proteome is a very complicated task, due to the wide dynamic range of concentration that separates the most abundant proteins and the less common ones (10-12 orders of magnitude). For this reason, plasma analysis requires pre-fractionation methods, and several such techniques are currently used to deplete albumin and other abundant plasma proteins.In this work we describe two different and optimized protocols to decrease the plasma proteome complexity for proteomic analysis. With this, comprehensive and systematic characterization of the plasma proteome in the healthy and diseased aortic stenosis (AS) state will greatly facilitate the development of "useful" biomarkers for early disease detection, clinical diagnosis, and therapy.