Abstract LB115: Simultaneous whole-body ultrasound contrast imaging: a novel high throughput preclinical platform for targeted molecular imaging studies

Abstract

Abstract Ultrasound contrast agent (UCA) based molecular imaging is a rapidly growing field in biomedical research. Ultrasound (US) is a non-radiative imaging modality that is frequently used to investigate various human diseases in the clinic. US molecular imaging is a novel imaging modality that utilizes targeted contrast agents to add molecular information about the imaging target, including vascular biomarkers of cancer. Pre-clinical animal models are commonly used to evaluate and validate targeted contrast agents before extending them for FDA-approval. Key impediments in the preclinical evaluations are the short in vivo half-life of microbubbles (MBs) (less than 30 minutes), limited transducer scanning area, and focusing one target at a time, which all make this strategy low throughput. Moreover, whole-body imaging strategy is not available for US imaging compared to other imaging modalities, such as PET, CT, and MRI. To overcome these imitations, we have developed a multi-mouse US imaging platform using an Automated Breast Volume Scanner (ABVS) system. In addition, we have synthesized a novel breast cancer vascular-specific B7-H3 targeted microbubbles (TMBs) using a microfluidic device. We tested these TMBs in a genetically engineered transgenic mice model [FVB/N-Tg (MMTV-PyMT)634Mul/J] (n=32) that develops breast cancer in the mammary fat pad. The US imaging results of conventional Vevo 2100 system indicated that B7-H3-TMBs could provide target specific contrast signals in the tumor vasculature compared to control MBs. We used this MBs for whole-body imaging using an ABVS system with two mice simultaneously in a stage. We imaged multiple tumors (10 tumors/mouse, 2 mice per scan, n=20 tumors) with a single bolus injection of TMBs per mouse. The results successfully showed tumor specific contrast signals from tumors independent of tumor size. Introduction of this whole-body scanner, and its ability to scan multiple mice simultaneously allows rapid imaging of multiple tumors with 3D quantification of tumor size by administering a single TMB injection enabling without significant contrast loss. Our approach makes this US-MI as high throughput and can be used to test multiple contrast agents for investigating different aspects of biological problems including screening of vascular biomarkers of human diseases. Citation Format: Arutselvan Natarajan, Farbod Tabesh, Dongwoon Hyun, Ramasamy Paulmurugan, Jeremy Dahl. Simultaneous whole-body ultrasound contrast imaging: a novel high throughput preclinical platform for targeted molecular imaging studies [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 2 (Clinical Trials and Late-Breaking Research); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(8_Suppl):Abstract nr LB115.