Immuno-PET Imaging of Tumour PD-L1 Expression in Glioblastoma.

ABSTRACT: There is no established method to assess the PD-L1 expression in brain tumours. Therefore, we investigated the suitability of affibody molecule (Z_PD-L1) radiolabelled with F-18 (Al¹⁸F) and Ga-68 to measure the expression of PD-L1 in xenograft mouse models of GBM. Mice bearing subcutaneous and orthotopic tumours were imaged 1 h post-radioconjugate administration. Ex vivo biodistribution studies and immunohistochemistry (IHC) staining were performed. Tumoural PD-L1 expression and CD4+/CD8+ tumour-infiltrating lymphocytes were evaluated in human GBM specimens. Z_PD-L1 was radiolabelled with radiochemical yields of 32.2 ± 4.4% (F-18) and 73.3 ± 1.8% (Ga-68). The cell-associated radioactivity in vitro was consistent with PD-L1 expression levels assessed with flow

SUBMITTER: Sharma G 

PROVIDER: S-EPMC10295898 | biostudies-literature | 2023 Jun

REPOSITORIES: biostudies-literature