Gelb Michael H, Lukacs Zoltan, Ranieri Enzo, Schielen Peter C J I
Departments of Chemistry and Biochemistry, University of Washington, Seattle, WA 98195, USA.
Newborn Screening and Metabolic Diagnostics Unit, Hamburg University Medical Center, Hamburg, Germany.
Int J Neonatal Screen. 2019 Mar;5(1). doi: 10.3390/ijns5010001. Epub 2018 Dec 21.
All worldwide newborn screening (NBS) for lysosomal storage diseases (LSDs) is performed as a first-tier test by measurement of lysosomal enzymatic activities in dried blood spots (DBS). The currently two available methodologies used for measurement of enzymatic activities are tandem mass spectrometry (MS/MS) and digital microfluidics fluorimetry (DMF-F). In this chapter we summarize the workflows for the two platforms. Neither platform is fully automated, but the relative ease of workflow will be dependent upon the specific operation of each newborn screening laboratory on a case-by-case basis. We provide the screen positive rate (the number of below cutoff newborns per 100,000 newborns) from all NBS laboratories worldwide carrying out MS/MS-based NBS of one or more LSDs. The analytical precision of the MS/MS method is higher than that for DMF-F as shown by analysis of a common set of quality control DBS by the Centers for Disease Control and Prevention (CDC). Both the MS/MS and DMF-F platforms enable multiplexing of the LSD enzymes. An advantage of MS/MS over DMF-F is the ability to include assays of enzymatic activities and biomarkers for which no fluorimetric methods exist. Advantages of DMF-F over MS/MS are: 1) Simple to use technology with same-day turn-around time for the lysosomal enzymes with the fastest rates compared to MS/MS requiring overnight analytical runs.; 2) The DMF-F instrumentation, because of its simplicity, requires less maintenance than the MS/MS platform.
全球范围内所有针对溶酶体贮积症（LSDs）的新生儿筛查（NBS），都是通过检测干血斑（DBS）中的溶酶体酶活性来作为一线检测方法。目前用于酶活性检测的两种可用方法是串联质谱（MS/MS）和数字微流控荧光法（DMF-F）。在本章中，我们总结了这两个平台的工作流程。两个平台都不是完全自动化的，但工作流程的相对简便程度将取决于每个新生儿筛查实验室的具体操作情况。我们提供了全球所有开展一种或多种基于MS/MS的LSDs新生儿筛查实验室的筛查阳性率（每10万名新生儿中低于临界值的新生儿数量）。美国疾病控制与预防中心（CDC）对一组常见的质量控制干血斑进行分析表明，MS/MS方法的分析精度高于DMF-F。MS/MS和DMF-F平台都能够对LSDs酶进行多重检测。MS/MS相对于DMF-F的一个优势是能够纳入那些不存在荧光法检测的酶活性和生物标志物检测。DMF-F相对于MS/MS的优势在于：1）技术使用简单，与需要过夜分析运行的MS/MS相比，溶酶体酶检测的周转时间为当天；2）由于DMF-F仪器设备简单，其维护需求比MS/MS平台少。
