Abstract:
Bi-allelic variants in VWA1, encoding Von Willebrand Factor A domain containing 1 protein localized to the extracellular matrix (ECM), were linked to a neuromuscular disorder with manifestation in child- or adulthood. Clinical findings indicate a neuromyopathy presenting with muscle weakness. Given that pathophysiological processes are still incompletely understood, and biomarkers are still missing, we aimed to identify blood biomarkers of pathophysiological relevance: white blood cells (WBC) and plasma derived from six VWA1-patients were investigated by proteomics. Four proteins, BET1, HNRNPDL, NEFM and PHGDH, known to be involved in neurological diseases and dysregulated in WBC were further validated by muscle-immunostainings unravelling HNRNPDL as a protein showing differences between VWA1-patients, healthy controls and patients suffering from neurogenic muscular atrophy and BICD2-related neuromyopathy. Immunostaining studies of PHGDH indicate its involvement in apoptotic processes via co-localisation with caspase-3. NEFM showed an increase in cells within the ECM in biopsies of all patients studied. Plasma proteomics unravelled dysregulation of 15 proteins serving as biomarker candidates among which a profound proportion of increased ones (6/11) are mostly related to antioxidative processes and have even partially been described as blood biomarkers for other entities of neuromuscular disorders before. CRP elevated in plasma also showed an increase in the extracellular space of VWA1-mutant muscle. Results of our combined studies for the first time describe pathophysiologically relevant biomarkers for VWA1-related neuromyopathy and suggest that VWA1-patient derived blood might hold the potential to study disease processes of clinical relevance, an important aspect for further preclinical studies.
摘要:
VWA1中的双等位基因变体,编码VonWillebrand因子A结构域,其中包含1个位于细胞外基质(ECM)的蛋白,与儿童或成年期表现的神经肌肉疾病有关。临床发现表明神经肌病表现为肌肉无力。鉴于病理生理过程仍未完全理解,生物标志物仍然缺失,我们旨在鉴定病理生理相关性的血液生物标志物:通过蛋白质组学研究了来自6例VWA1患者的白细胞(WBC)和血浆.四种蛋白质,BET1,HNRNPDL,NEFM和PHGDH,已知与神经系统疾病有关并在WBC中失调,通过肌肉免疫染色进一步验证了HNRNPDL作为一种显示VWA1患者之间差异的蛋白质,健康对照和患有神经源性肌萎缩和BICD2相关神经肌病的患者。PHGDH的免疫染色研究表明其通过与caspase-3共定位参与凋亡过程。NEFM显示所有研究患者的活组织检查中ECM内的细胞增加。血浆蛋白质组学揭示了作为生物标志物候选物的15种蛋白质的失调,其中大量增加的蛋白质(6/11)主要与抗氧化过程有关,甚至部分被描述为神经肌肉疾病其他实体的血液生物标志物。血浆中CRP升高也显示VWA1突变肌肉的细胞外空间增加。我们的联合研究结果首次描述了VWA1相关神经肌病的病理生理相关生物标志物,并表明VWA1患者来源的血液可能具有研究临床相关性疾病过程的潜力。进一步临床前研究的一个重要方面。