Proteomic Analysis of Kidney Preservation Solutions Prior to Renal Transplantation

One of the main issues in kidney transplantation is the optimal functional preservation of the organ until its transplantation into the appropriate recipient. Despite intensive efforts, the functional preservation period remains limited to hours. During this time, as a result of cellular injury, various proteins, peptides, and other molecules are released by the organ into the preservation medium. In this study, we used proteomic techniques to analyze the protein profiles of preservation solutions in which organs had been preserved prior to their transplantation. Samples were obtained from the preservation solutions of 25 deceased donor kidneys scheduled for transplantation. The protein profiles of the solutions were analyzed using 2D gel electrophoresis/MALDI-TOF and LC-MS/MS. We identified and quantified 206 proteins and peptides belonging to 139 different groups. Of these, 111 proteins groups were belonging to kidney tissues. This study used proteomic techniques to analyze the protein profiles of organ preservation solutions. These findings will contribute to the development of improved preservation solutions to effectively protect organs for transplantation.

Development and validation of a generic method for quantification of collagen in food supplement tablets using liquid chromatography coupled with time-of-flight mass spectrometry

A generic method for the quantification of type II collagen in protein-based dietary supplements is described. This quantitative analysis was conducted using liquid chromatography-electrospray ionization-time-of-flight mass spectrometry (LC-ESI-TOF MS). Compared to classical methods with the use of isotope-labeled standards, our method includes, for the first time, the quantification of hydroxyproline using histidine as an internal standard. Separation of the analytes was performed on a Phenomenex Synergi 4 μm Fusion-RP 80 Ǻ column (150 × 2.0 mm, 4.0 μm) with a mobile phase made of 10 mM ammonium formate in water (A) and 10 mM ammonium formate in methanol (B). The assay was fully validated according to FDA guidelines, and the method exhibited sufficient specificity, accuracy, and precision. Intra- and inter-batch accuracy, determined as a deviation between nominal and measured values, ranged from -4.8 to 9.1% and from 0.9 to 6.4 %, respectively. All analytes (hydroxyproline and histidine) at three concentration levels showed extraction recoveries from 89 to 98 %. The method was successfully applied to protein-based dietary supplements of the pharmaceutical industry.