Dataset Information

ImmunoPET imaging of TIGIT in the glioma microenvironment.

ABSTRACT: Glioblastoma (GBM) is the most common primary malignant brain tumor. Currently, there are few effective treatment options for GBM beyond surgery and chemo-radiation, and even with these interventions, median patient survival remains poor. While immune checkpoint inhibitors (ICIs) have demonstrated therapeutic efficacy against non-central nervous system cancers, ICI trials for GBM have typically had poor outcomes. TIGIT is an immune checkpoint receptor that is expressed on activated T-cells and has a role in the suppression of T-cell and Natural Killer (NK) cell function. As TIGIT expression is reported as both prognostic and a biomarker for anti-TIGIT therapy, we constructed a molecular imaging agent, [⁸⁹Zr]Zr-DFO-anti-TIGIT (⁸⁹Zr-αTIGIT), to visualize TIGIT in preclinical GBM by immunoPET imaging. PET imaging and biodistribution analysis of ⁸⁹Zr-αTIGIT demonstrated uptake in the tumor microenvironment of GBM-bearing mice. Blocking antibody and irrelevant antibody tracer studies demonstrated specificity of ⁸⁹Zr-αTIGIT with significance at a late time point post-tracer injection. However, the magnitude of ⁸⁹Zr-αTIGIT uptake in tumor, relative to the IgG tracer was minimal. These findings highlight the features and limitations of using ⁸⁹Zr-αTIGIT to visualize TIGIT in the GBM microenvironment.

SUBMITTER: Vincze SR

PROVIDER: S-EPMC10912309 | biostudies-literature | 2024 Mar

REPOSITORIES: biostudies-literature

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ImmunoPET imaging of TIGIT in the glioma microenvironment.

Vincze Sarah R SR Jaswal Ambika P AP Frederico Stephen C SC Nisnboym Michal M Li Bo B Xiong Zujian Z Sever ReidAnn E RE Sneiderman Chaim T CT Rodgers Mikayla M Day Kathryn E KE Latoche Joseph D JD Foley Lesley M LM Hitchens T Kevin TK Frederick Robin R Patel Ravi B RB Hadjipanayis Costas G CG Raphael Itay I Nedrow Jessie R JR Edwards W Barry WB Kohanbash Gary G

Scientific reports 20240304 1

Glioblastoma (GBM) is the most common primary malignant brain tumor. Currently, there are few effective treatment options for GBM beyond surgery and chemo-radiation, and even with these interventions, median patient survival remains poor. While immune checkpoint inhibitors (ICIs) have demonstrated therapeutic efficacy against non-central nervous system cancers, ICI trials for GBM have typically had poor outcomes. TIGIT is an immune checkpoint receptor that is expressed on activated T-cells and h ...[more]

PMID: 38438420

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Dataset Information

ImmunoPET imaging of TIGIT in the glioma microenvironment.

Publications

ImmunoPET imaging of TIGIT in the glioma microenvironment.

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