Serum Antibody Profiling with a Carbohydrate Microarray

生物标志物在癌症诊断和治疗中起着至关重要的作用。抗体是一类重要的生物标记物，具有良好的稳定性、在生物流体中的可及性和易于检测等优点。在识别蛋白质抗原的抗体水平变化方面已经进行了广泛的研究；然而，结合碳水化合物抗原的抗体分析在很大程度上没有得到充分利用。我们的碳水化合物微阵列非常适合监测人类血清中的抗聚糖抗体，并研究其水平在疾病反应或疾病治疗中的变化。高通量方法可用于识别新的单一生物标记物或识别可用作生物标记物的变化或概况的组合。我们已经开发并验证了一种碳水化合物微阵列测定法，用于测量人血清中的抗体水平。我们已经使用该阵列来表征健康个体的自然抗体收集，并评估协变量与抗体水平之间的关系。我们没有发现基于性别、种族或地理位置的显著差异。然而，统计上的显著差异与血型和年龄有关。此外，我们评估了个体随时间的变化，发现抗体水平在3-13周内保持稳定。这些信息对于识别超出自然变化水平的变化至关重要。与Schlom博士及其同事合作，我们一直在使用该阵列来评估对PSA-TRICOM前列腺癌疫苗的免疫反应。此外，我们还评估了锁孔帽贝血青素（KLH）的反应，这是一种用于预防膀胱癌术后复发的免疫治疗药物。

Biomarkers play a critical role in cancer diagnosis and treatment. Antibodies represent an important class of biomarkers with many advantageous features such as good stability, accessibility in biofluids, and easy detection. There has been extensive research on identifying changes in antibody levels to protein antigens; however, analysis of antibodies that binding carbohydrate antigens have been largely underutilized. Our carbohydrate microarray is well-suited to monitor the repertoire of anti-glycan antibodies in human serum and to study changes in their levels in response to disease or treatment of disease. The high-throughput approach can be used to identify new single biomarkers or to identify combinations of changes or profiles that are useful as biomarkers. We have developed and validated a carbohydrate microarray assay for measuring antibody levels in human serum. We have used the array to characterize the natural collection of antibodies in healthy individuals and to evaluate relationships between covariates and antibody levels. We have found no significant differences based on gender, race, or geographic location. However, statistically significant differences were associated with blood type and age. In addition, we have evaluated changes within individuals over time and found that antibody levels are stable over periods of 3-13 weeks. This information is critical for identifying changes that are beyond the natural level of variation. In collaboration with Dr. Schlom and colleagues, we have been using the array to evaluate immune responses to the PSA-TRICOM prostate cancer vaccine. In addition, we have evaluated responses to keyhole limpet hemocyanin (KLH), an immunotherapeutic agent used to prevent recurrence of bladder cancer after surgery.