High Throughput Proteomic Exploration of Hypothermic Preservation Reveals Active Processes within the Cell Associated with Cold Ischemia Kinetic

Abstract

The demand for organs to be transplanted increases pressure on procurement centers, to the detriment of organ quality, increasing complications. New preservation protocols are urgently needed, requiring an in-depth understanding of ischemia-reperfusion mechanisms. We performed a proteomic analysis using LC-MS/MS-TOF data analyzed through R software and Cytoscape's ClueGO application, comparing the proteome of kidney endothelial cells, key cell type, subjected to 3, 6, 12, 19, and 24 h of cold ischemia and 6 h reperfusion. Critical pathways such as energy metabolism, cytoskeleton structure/transport system, and gene transcription/translation were modulated. Important time windows were revealed: a—during the first 3 h, central proteins were upregulated within these pathways; b—the majority of these upregulations were maintained until 12 h cold ischemia time (CIT); c—after that time, the overall decrease in protein expression was observed; d—at reperfusion, proteins expressed in response to cold ischemia were all downregulated. This shows that cold ischemia is not a simple slowing down of metabolism, as deep changes take place within the proteome on major pathways. Time-sensitive expression of key protein reveals possible quality biomarkers as well as potential targets for new strategies to maintain or optimize organ quality.

Biomarker-Development Proteomics in Kidney Transplantation: An Updated Review

“…This process can cause PNF or DGF and episodes of acute rejection and transplant fibrosis. Notably, 12 h is the preservation time after which reperfusion induces cell death, with an intensity proportional to the preservation time [ 29 , 30 ].…”

“…Their study suggests that efforts to quench IRI should focus on preserving or restoring metabolic competence [ 31 ]. In a more recent study, Pasini-Chabot et al [ 30 ] investigated the proteome of kidney endothelial cells (the first cell line impacted by IRI) subjected to cold ischemia for 3–24 h and 6 h of reperfusion. After LC-MS/MS analysis, a heatmap was generated to distinguish protein motifs by their variation, and each group was analyzed using the Cytoscape’s ClueGO application to identify ontology and network associations.…”

“…Upon reperfusion, all expressed proteins were downregulated and no new proteins were detected. This study indicates key proteins for investigation as potential targets for novel strategies to optimize organ quality [ 30 ]. These results are summarized in Table 2 .…”