ImmunoPET imaging of TIGIT in the glioma microenvironment.

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.

Impact of Sex on COVID-19 Media Exposure, Anxiety, Perceived Risk, and Severity in Middle-Aged and Older Adults.

OBJECTIVES: To examine associations between COVID-19 media exposure and anxiety/perceived risk/severity and investigate their dependency on sex in middle-aged/older adults. METHODS: Adults aged 50+ years completed online surveys: Coronavirus Anxiety Scale, COVID-19 media exposure, COVID-19 media dependency for health information, and COVID-19 perceived risk and severity. Multiple regressions examined independent and interactive (with sex) associations between COVID-19 media exposure/dependency and COVID-19 anxiety/perceived risk and severity. Analyses controlled for age, education, race, total medical conditions, and COVID-19 status. RESULTS: Higher COVID-19 media exposure was associated with higher COVID-19 anxiety among men (not women) and higher perceived risk/severity in both sexes. Higher COVID-19 media dependency was associated with higher COVID-19 anxiety and perceived risk/severity in both sexes. CONCLUSION: In middle-aged/older adults, the use/dependency of media for COVID-19 information may be linked to negative psychological health and increased COVID-19 perceived risk and severity. Men may be at increased risk of anxiety related to media exposure.