Development of the GlycoFibrotyper for detection of liver fibrosis

越来越多地，血清或血浆或最丰富的N-连接葡聚糖的变化已被报道 血清糖蛋白，免疫球蛋白G，来自代表类风湿性关节炎的大样本队列， 消化系统疾病、癌症和肝纤维化。在纤维化的情况下，两项测试已经确定了N- 总的免疫球蛋白和特定的免疫球蛋白分子上的连接糖基化。这两种测试都可以检测到 显著的纤维化，具有高度的准确性，并且还能够检测到中等水平的纤维化。 然而，这两种测试都有缺点，因为它们需要专门的样品处理资源， 在分析之前进行加工和提纯，而且试剂和加工都很昂贵。 我们团队最近开发了一种简化的抗体捕获载玻片阵列方法，以直接分析 捕获的血清糖蛋白的N-糖链，如免疫球蛋白，一种需要几微升样本和简化的方法 在分析之前不需要提纯或糖类修改的处理工作流程。此父方法是 称为GlycoTyper。在这种方法中，从捕获的抗体中释放N-连接的多糖 糖蛋白，直接用MALDI-TOF质谱仪分析，如Bruker Tissetyper MALDI-TOF，已经在临床实验室中使用。我们假设这种方法可以用来 确定反映许多疾病发展过程中发生的变化的葡聚糖生物标志物， 包括这里所做的肝纤维化/肝硬变。

Increasingly, alterations in N-linked glycans have been reported for serum or plasma, or for the most abundant serum glycoprotein, immunoglobulin G, from large cohorts of samples representing rheumatoid arthritis, digestive diseases, cancer and liver fibrosis. In the case of fibrosis, two tests have identified alterations in N- linked glycosylation on both total IgG populations and on specific IgG molecules. Both of these tests can detect significant fibrosis with a high degree of accuracy and are also able to detect intermediate levels of fibrosis. However, both tests have drawbacks in that they require specialized sample handling resources, extensive processing and purification prior to analysis, and are expensive in regards to reagents and processing. Our group has recently developed a streamlined antibody capture slide array approach to directly profile N-glycans of captured serum glycoproteins like IgG, a method requiring a few microliters of sample and simplified processing workflows that require no purification or sugar modifications prior to analysis. This parent method is referred to as the GlycoTyper. In this method, N-linked glycans are released from antibody captured glycoproteins and are directly analyzed by MALDI-TOF mass spectrometry, such as the Bruker Tissuetyper MALDI-TOF, which is already available in clinical laboratories. We hypothesize that this method can be used to identify glycan biomarkers reflective of the changes that occur during the development of many diseases, including liver fibrosis/cirrhosis as performed here.