PET Imaging of Tumor PD-L1 Expression with a Highly Specific Nonblocking Single-Domain Antibody.

ABSTRACT: Although immunotherapy through programmed death 1/programmed death ligand 1 (PD-1/PD-L1) checkpoint blockade has shown impressive clinical outcomes, not all patients respond to it. Recent studies have demonstrated that the expression level of PD-L1 in tumors is one of the factors that correlate with PD-1/PD-L1 checkpoint blockade therapy. Herein, a ⁶⁸Ga-labeled single-domain antibody tracer, ⁶⁸Ga-NOTA-Nb109, was designed and developed for specific and noninvasive imaging of PD-L1 expression in a melanoma-bearing mouse model. Methods: The single-domain antibody Nb109 was labeled with the radionuclide ⁶⁸Ga through a NOTA chelator. An in vitro binding assay was performed to assess the affinity and binding epitope of Nb109 to PD-L1. The clinical applicat

SUBMITTER: Lv G 

PROVIDER: S-EPMC6954462 | biostudies-literature | 2020 Jan

REPOSITORIES: biostudies-literature