Service de Pharmacologie et Immunoanalyse (SPI), CEA, INRA, Université Paris-Saclay , Gif-sur Yvette F-91191 , France.
Université Paris 7 Cité Sorbonne, UMR INSERM 1160 , 110 Avenue de Verdun , Paris 75010 , France.
J Proteome Res. 2020 Feb 7;19(2):914-925. doi: 10.1021/acs.jproteome.9b00690. Epub 2020 Jan 22.
Well-characterized prognostic biomarkers and reliable quantitative methods are key in sepsis management. Among damage-associated molecular patterns, S100A8/S100A9 complexes are reported to be markers for injured cells and to improve the prediction of death in septic shock patients. In view of the structural diversity observed for the intracellular forms, insight into circulating complexes and proteoforms is required to establish prognostic biomarkers. Here, we developed top-down and bottom-up proteomics to characterize the association of S100A8 and S100A9 in complexes and major circulating proteoforms. An antibody-free method was developed for absolute quantification of S100A8/S100A9 in a cohort of 49 patients to evaluate the prognostic value on the first day after admission for septic shock. The predominant circulating forms identified by top-down proteomics were S100A8, mono-oxidized S100A8, truncated acetylated S100A9, and S-nitrosylated S100A9. S100A8, truncated acetylated S100A9, and mono-oxidized S100A8 discriminated between survivors and nonsurvivors, along with total S100A8/S100A9 measured by the antibody-free bottom-up method. Overall, new insights into circulating S100A8/S100A9 and confirmation of its prognostic value in septic shock are crucial in qualification of this biomarker. Also, the simple antibody-free assay would support the harmonization of S100A8/S100A9 measurements.
特征明确的预后生物标志物和可靠的定量方法是脓毒症管理的关键。在损伤相关分子模式中，S100A8/S100A9 复合物被报道为受损细胞的标志物，并能提高脓毒性休克患者死亡的预测能力。鉴于观察到细胞内形式的结构多样性，需要深入了解循环复合物和蛋白质形式，以建立预后生物标志物。在这里，我们开发了自上而下和自下而上的蛋白质组学来描述 S100A8 和 S100A9 在复合物和主要循环蛋白质形式中的关联。开发了一种无抗体的方法来绝对定量 49 例脓毒性休克患者入院后第一天的 S100A8/S100A9，以评估其预后价值。通过自上而下的蛋白质组学鉴定的主要循环形式是 S100A8、单氧化 S100A8、截断乙酰化 S100A9 和 S-亚硝化 S100A9。S100A8、截断乙酰化 S100A9 和单氧化 S100A8 可区分存活者和非存活者，同时通过无抗体的自下而上方法测量的总 S100A8/S100A9 也可区分。总的来说，对循环 S100A8/S100A9 的新见解及其在脓毒性休克中的预后价值的确认对于该生物标志物的定性至关重要。此外，简单的无抗体检测方法将支持 S100A8/S100A9 测量的标准化。
