The need for a reliable and accurate method to quantify dystrophin proteins in human skeletal muscle biopsies has become crucial in order to assess the efficacy of dystrophin replacement therapies in Duchenne muscular dystrophy as well as to gain insight into the relationship between dystrophin levels and disease severity in Becker's muscular dystrophy. Current methods to measure dystrophin such as western blot and immunofluorescence, while straightforward and simple, lack precision and sometimes specificity. Here, we standardized a targeted mass spectrometry method to determine the absolute amount of dystrophin in ng/mg of muscle using full-length 13 C6-Arg- and 13 C6,15 N2-Lys-labeled dystrophin and parallel reaction monitoring (PRM). The method was found to be reproducible with a limit of quantification as low as 30 pg of dystrophin protein per mg of total muscle proteins. The method was then tested to measure levels of dystrophin in muscle biopsies from a healthy donor and from Duchenne and Becker's muscular dystrophy patients.

中文翻译：

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使用平行反应监测（PRM）对人肌肉活组织检查中的肌营养不良蛋白进行绝对定量。

为了评估肌营养不良蛋白替代疗法在杜氏肌营养不良症中的疗效以及深入了解肌营养不良蛋白水平与疾病严重程度之间的关系，需要一种可靠，准确的方法来定量人骨骼肌活检组织中的肌营养不良蛋白已变得至关重要。贝克尔的肌营养不良症。目前测量肌营养不良蛋白的方法，例如蛋白质印迹和免疫荧光，虽然简单明了，却缺乏准确性，有时还缺乏特异性。在这里，我们使用全长13 C6-Arg-和13 C6,15 N2-Lys标记的肌营养不良蛋白和平行反应监测（PRM），对靶向质谱法进行标准化，以测定肌肉中ng / mg肌营养不良蛋白的绝对量。发现该方法可重现，定量限低至每毫克总肌肉蛋白30 pg肌营养不良蛋白。然后对该方法进行了测试，以测量健康捐献者以及Duchenne和Becker肌肉营养不良患者的肌肉活检中肌营养不良蛋白的水平。