Translocator Protein 18 kDa Tracer 18F-FDPA PET/CTA Imaging for the Evaluation of Inflammation in Vulnerable Plaques

• DOI: 10.1021/acs.molpharmaceut.4c00344
• Publication Date: 2024-05-31T16:12:03Z
• Authors: Jian Jiao; Biao Hu; Tiantian Mou; Quan Li; Yi Tian; Nan Zhang; Ying Zhang; Mingkai Yun; Nan Nan; Jing Tian; Wei Yu; Hongzhi Mi; Wei Dong; Xiantao Song
• Keywords: Translocator protein; Molecular Imaging; TRACER; PET Imaging

Inflammation induced by activated macrophages within vulnerable atherosclerotic plaques (VAPs) constitutes a significant risk factor for plaque rupture. Translocator protein (TSPO) is highly expressed in macrophages. This study investigated the effectiveness of TSPO radiotracers, 18F-FDPA, detecting VAPs and quantifying inflammation rabbits. 18 New Zealand rabbits were divided into 3 groups: sham group A, VAP model B, evolocumab treatment C. 18F-FDPA PET/CTA imaging was performed at 12, 16, 24 weeks all groups. Optical coherence tomography (OCT) on abdominal aorta weeks. The defined through OCT images, ex vivo PET also SUVmax SUVmean measured target organ, target-to-background ratio (TBRmax) calculated as SUVmax/SUVblood pool. arterial sections isolated analyzed HE staining, CD68 immunofluorescence Western blot. results showed that weeks, TBRmax B significantly higher than groups A Immunofluorescence staining TSPO, well blot, confirmed increased expression corresponding regions B. revealed an presence lipid core, multiple foam cells, inflammatory cell infiltration area with high uptake. indicates correlation between uptake, severity, VAPs. TSPO-targeted tracer shows specific uptake macrophage-rich plaques, making it valuable tool assessing