Carbohydrate Microarray Profiling of Glycan-Binding Antibodies and Lectins

癌细胞在疾病的发作和进展期间经历碳水化合物表达的急剧变化。因此，人们对理解为什么会发生这些变化、它们如何导致疾病以及将这些变化用于临床用途产生了相当大的兴趣。由于几个原因，碳水化合物结合抗体和凝集素在这项研究中起着关键作用。首先，抗体和凝集素被广泛用于检测和监测碳水化合物表达的变化。在这方面，它们被用于基础研究，作为诊断剂和治疗剂。全面了解其特异性对于正确使用和解释结果至关重要。直到最近，这方面的信息还不容易获得。随着碳水化合物微阵列技术或聚糖阵列的出现，我们现在可以快速分析这些蛋白质与各种碳水化合物抗原的结合。在过去，我们已经筛选了大量的商业上可用的凝集素和抗体试剂在研究界使用。我们发现，许多这些试剂没有显示出预期的特异性。我们提供的关于特异性的信息将使这些试剂能够更好地使用，并有助于结果的解释。此外，我们还与德国癌症研究所Abeome Corp.的研究人员合作，对选定的抗体和凝集素进行了分析，和华盛顿大学圣路易斯分校在每种情况下，抗体和凝集素选择性地结合肿瘤并显示抗癌活性。它们似乎与聚糖结合，但碳水化合物配体的身份未知。该阵列已被用来分析这些蛋白质的结合特性，并确定其配体。此外，该阵列可用于开发新的抗体和凝集素，以监测新的碳水化合物抗原。该阵列被用于开发新的单克隆抗体。例如，我们已经开发并选择了结合GalNl 1 -3Gal抗原的抗体。使用这些抗体，我们发现这种碳水化合物抗原改变了宫颈鳞状细胞癌的表达，并且表达的变化与预后相关。

Cancer cells undergo dramatic changes in carbohydrate expression during the onset and progression of disease. As a result, there has been considerable interest in understanding why these changes occur, how they contribute to the disease, and exploiting these changes for clinical use. Carbohydrate binding antibodies and lectins play a critical role in this research for several reasons. First, antibodies and lectins are used extensively to detect and monitor changes in carbohydrate expression. In this capacity, they are used for basic research, as diagnostics, and as therapeutic agents. A comprehensive understanding of their specificity is critical for proper use and interpretation of results. Until recently, this information was not readily available. With the advent of carbohydrate microarray technology, or glycan arrays, we can now rapidly analyze binding of these proteins to a wide variety of carbohydrate antigens. In the past, we have screened a large set of commercially available lectin and antibody reagents used in the research community. We found that many of these reagents did not display the expected specificity. The information we provided regarding specificity will enable better use of these reagents and facilitate interpretation of results. In addition, we have been profiling selected antibodies and lectins in collaborations with researchers at the German Cancer Research Institute, Abeome Corp., and University of Washington-St. Louis. In each case, the antibodies and lectins selectively bind tumors and display anti-cancer activity. They appeared to bind glycans, but the identities of the carbohydrate ligand(s) were unknown. The array has been used to profile the binding properties of these proteins and identify their ligands. In addition, the array can be used to develop new antibodies and lectins for monitoring new carbohydrate antigens. The array is being used to develop new monoclonal antibodies. For example, we have developed and selected antibodies that bind the GalNAca1-3Gal antigen. Using these antibodies, we have found that this carbohydrate antigen has altered expression on squamous cell carcinomas of the cervix and that changes in expression correlate with prognosis.