The following is a summary of “Perfusate Proteomes Provide Biological Insight Into Oxygenated Versus Standard Hypothermic Machine Perfusion in Kidney Transplantation,” published in the November 2023 issue of Surgery by Mulvey, et al.
For a study, researchers used mass spectrometry to examine perfusate samples from a phase 3 randomized double-blind paired clinical trial of hypothermic machine perfusion with and without oxygen (COMPARE). This helped them understand how key biological changes happen in donation after the circulatory death of kidneys during continuous perfusion. New perfusion methods have been shown to help patients and better protect donated organs. However, many biological processes that may change during perfusion have yet to be studied. During the COMPARE clinical experiment, repeated perfusate samples were collected. These samples gave scientists a unique way to look into perfusate proteome profiles. The idea was that in-depth analysis might show medically relevant information about how donor kidneys gain from this intervention.
They used multiplexed liquid chromatography-tandem mass spectrometry to get a summary of the proteomes of 210 perfusate samples. They used partial least squares discriminant analysis and multivariate analysis with clinical and circulatory data to find links between traits and clinical results. Characterizing and measuring 1,716 proteins showed that proteins released during perfusion come from kidney tissue and blood, with blood-based proteins making up the majority.
The total length of time that a hypothermic machine perfuses is linked to higher amounts of a certain group of proteins. High-density lipoprotein and complement cascade proteins are linked to results at 12 months, and blood-derived proteins are more common in the perfusion fluid of kidneys that developed severe rejection. Perfusate analysis by mass spectrometry was useful because it showed changes in proteins that have biological significance and helped explain some of the clinical findings from the COMPARE study.
