Abstract
Depletion of major plasma proteins is a major technique to gain access to low abundant biomarker proteins. Immunodepletion columns arc often used for this purpose. They are available in different formats depending on the number of major proteins removed. The goal of the current study was to compare and validate available columns to deplete major camel plasma proteins. Plasma samples typically have 1-5 proteins that account for 90% of the total protein mass in the samples. In order to detect and monitor the less abundant proteins, an effective and reproducible method to deplete the abundant proteins is required. Six different methods were tested to deplete abundant proteins in camel plasma. Using different immunodepletion column technologies, one method was superior over other methods and provided depletion of greater than 90% of the total protein and allowed more than 20 distinct protein bands to be observed on SDS-PAGE gels stained with coomassie blue. Further optimization was performed with this depletion method to determine the optimal amount of starting material. In this study, we present an optimized camel plasma depletion method that may facilitate protein biomarker discovery for many mammalian diseases.