Yeast surface display-based screening and preliminary characterization of nectin-4-targeting nanobodies for bladder cancer.

BACKGROUND

Advanced bladder cancer (BCa) is associated with a poor prognosis, highlighting the urgent need for novel therapeutic strategies with improved efficacy and reduced toxicity. Nectin-4 (PVRL4, here after referred to as N4) is a clinically validated therapeutic target; however, existing antibody-based agents are limited by inadequate tumor penetration and off-target toxicities. Nanobodies (Nbs) possess favorable characteristics, including small molecular size, enhanced tissue penetration, and ease of sengineering. This study aimed to identify and preliminarily characterize N4-targeting Nb candidates for BCa using a yeast surface display-based screening strategy.

RESULTS

N4 was highly expressed in BCa and significantly associated with an unfavorable prognosis. The YSD platform supported efficient library expansion, surface display, and iterative enrichment of N4-binding clones. Among the identified Nbs, Nb-80 exhibited apparent binding activity, with an EC₅₀ of 0.150 μg/mL. BLI analysis demonstrated rapid association-dissociation kinetics.

CONCLUSIONS

An N4-binding Nb candidate was identified and preliminarily characterized using a YSD-based screening strategy. These findings support the utility of the YSD platform for Nb discovery and provide a preliminary basis for further validation of N4-targeting Nb candidates in BCa.

CLINICAL TRIAL NUMBER: Not applicable.