Label-Free Microfiber Biosensor Reveals PD-L1 Autoantibodies as Predictive Biomarkers in Esophageal Squamous Cell Carcinoma
Zefeng Li, Ruen Xie, Xin Wang, Yu Xie, Shengyu Liu, Zijie Xv, Jianlong Luo, Yuping Chen, Jingsheng Lun, Houchang Li, Jingao Zhang, Haili Ma, Shengli Pu, Lan Rao, Xinzhu Sang, Gerald Farrell, Jinhui Yuan, Shaobin Chen, Qiang WuAbstract
Heterogeneity in patient response to immunotherapy remains a major challenge in precision oncology. Here, the predictive value of serum programmed death-ligand 1 autoantibody (PD-L1 AAb) has been investigated for predicting response to neoadjuvant chemoimmunotherapy in patients with esophageal squamous cell carcinoma (ESCC), enabled by a label-free microfiber ring laser biosensor. The detection range of the microfiber biosensor for PD-L1 AAb concentrations is 1 to 250 ng/mL with a limit of detection of 0.069 ng/mL, and an assay time of 20 min. In a cohort of 42 ESCC patients, receiver operating characteristic curve analysis showed that PD-L1 AAbs achieved a higher area under the curve (AUC) than guideline-recommended PD-L1 immunohistochemistry-based combined positive score assessment, with an 11.68% increase in AUC. These results suggest that serum PD-L1 AAbs have potential as an exploratory predictive biomarker for neoadjuvant therapy response and the microfiber biosensor has potential as a tool for rapid immunotherapy stratification.