Obry Antoine, Lequerré Thierry, Hardouin Julie, Boyer Olivier, Fardellone Patrice, Philippe Peggy, Le Loët Xavier, Cosette Pascal, Vittecoq Olivier
INSERM, U905, Pathophysiology and Biotherapy of Inflammatory and Autoimmune Diseases, F-76000 Rouen, France; CNRS, UMR 6270, Polymers, Biopolymers and Surfaces, F-76821 Mont Saint Aignan, France; PISSARO Proteomics Facility, F-76821 Mont Saint Aignan, France; Normandy University, Institute of Research and Innovation in Biomedecine, F-76821 Mont Saint Aignan, France.
INSERM, U905, Pathophysiology and Biotherapy of Inflammatory and Autoimmune Diseases, F-76000 Rouen, France; Normandy University, Institute of Research and Innovation in Biomedecine, F-76821 Mont Saint Aignan, France; Department of Rheumatology, Rouen University Hospital, F-76000 Rouen, France; INSERM, Centre d'investigation clinique 1404, F-76000 Rouen, France.
PLoS One. 2014 Dec 29;9(12):e115800. doi: 10.1371/journal.pone.0115800. eCollection 2014.
One way to optimize the drug prescription in rheumatoid arthritis (RA) is to identify predictive biomarkers of drug responsiveness. Here, we investigated the potential "theranostic" value of proteins of the S100 family by monitoring levels of both S100A8 and S100A9 in blood samples from RA patients.
For proteomic analysis, peripheral blood mononuclear cells (PBMC) and serum samples were collected in patients prior to initiation of the methotrexate/etanercept (MTX/ETA) combination. Firstly, relative mass spectrometry (MS) quantification focusing on S100A8 and S100A9 proteins was carried out from PBMCs samples to identify potential biomarkers. The same approach was also performed from serum samples from responder (R) and non responder (NR) patients. Finally, to confirm these results, an absolute quantification of S100A8, S100A9 proteins and calprotectin (heterodimer of S100A8/S100A9) was carried out on the serum samples using ELISA.
MS analyses revealed that both S100A8 and S100A9 proteins were significantly accumulated in PBMC from responders. In contrast to PBMC, only the S100A9 protein was significantly overexpressed in the serum of R patients. Absolute quantification by ELISA confirmed this result and pointed out a similar expression level of S100A8 protein and calprotectin in sera from both R and NR groups. Thus, the S100A9 protein revealed to be predictive of MTX/ETA responsiveness, contrarily to parameters of inflammation and auto-antibodies which did not allow significant discrimination.
This is the first report of an overexpression of S100A9 protein in both PBMCs and serum of patients with subsequent response to the MTX/ETA combination. This protein thus represents an interesting biomarker candidate of therapeutic response in RA.
优化类风湿关节炎（RA）药物处方的一种方法是识别药物反应性的预测生物标志物。在此，我们通过监测RA患者血样中S100A8和S100A9的水平，研究了S100家族蛋白的潜在“治疗诊断”价值。
对于蛋白质组学分析，在开始使用甲氨蝶呤/依那西普（MTX/ETA）联合治疗之前，收集患者的外周血单个核细胞（PBMC）和血清样本。首先，对PBMC样本进行聚焦于S100A8和S100A9蛋白的相对质谱（MS）定量，以识别潜在的生物标志物。对反应者（R）和无反应者（NR）患者的血清样本也采用相同方法。最后，为证实这些结果，使用酶联免疫吸附测定（ELISA）对血清样本中的S100A8、S100A9蛋白和钙卫蛋白（S100A8/S100A9异二聚体）进行绝对定量。
MS分析显示，反应者的PBMC中S100A8和S100A9蛋白均显著积累。与PBMC不同，仅S100A9蛋白在R患者血清中显著过表达。ELISA绝对定量证实了这一结果，并指出R组和NR组血清中S100A8蛋白和钙卫蛋白的表达水平相似。因此，与炎症参数和自身抗体不同，S100A9蛋白显示出可预测MTX/ETA反应性，炎症参数和自身抗体无法实现显著区分。
这是首次报道S100A9蛋白在对MTX/ETA联合治疗有后续反应的患者的PBMC和血清中均过表达。因此，该蛋白是RA治疗反应中一个有意义的生物标志物候选物。
