Screening, Construction, and Preliminary Evaluation of CLDN18.2-Specific Peptides for Noninvasive Molecular Imaging

作者：Zilei Wang, Chuanke Zhao, Jin Ding, Yan Chen, Jiayue Liu, Xingguo Hou, XiangXing Kong, Bin Dong, Zhi Yang, Hua Zhu · 发表于：ACS Pharmacology & Translational Science · 年份：2023 · DOI：10.1021/acsptsci.3c00165 · 被引用次数：13 · 研究领域：Monoclonal and Polyclonal Antibodies Research、Glycosylation and Glycoproteins Research、Nanoparticle-Based Drug Delivery

Recent global clinical trials have shown that CLDN18.2 is an ideal target for the treatment of gastric cancer and that patients with high CLDN18.2 expression can benefit from targeted therapy. Therefore, accurate and comprehensive detection of CLDN18.2 expression is important for patient screening and guidance in anti-CLDN18.2 therapy. Phage display technology was used to screen CLDN18.2-specific peptides from 100 billion libraries. 293T CLDN18.1 cells were used to exclude nonspecific binding and CLDN18.1 binding sequences, while 293T CLDN18.2 cells were used to screen CLDN18.2-specific binding peptides. The monoclonal clones obtained from phage screening were sequenced, and peptides were synthesized based on the sequencing results. Binding specificity and affinity were assessed with a fluorescein isothiocyanate (FITC)-conjugated peptide. A 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA)-conjugated peptide was also synthesized for 68 Ga radiolabeling. The in vitro and in vivo stability, partition coefficients, in vivo molecular imaging, and biodistribution were also characterized. Overall, 54 monoclonal clones were selected after phage display screening. Subsequently, based on the cell ELISA results, CLDN18.2 preference monoclonal clones were selected for deoxyribonucleic acid (DNA) sequencing, and four 7-peptide sequences were obtained after sequence comparison; among them, a peptide named T37 was further validated in vitro and in vivo . The T37 peptide speci...