Preliminary study on targeting microbubbles with dual-modality ultrasound/near-infrared fluorescence for identifying early inflammatory response in coronary microcirculation dysfunction
Y Mu, X Xu, Z Wang, Q Zhang, Y Wang, Y Han, L Liu, C Yuan, T Ma, S ChenAbstract
Background
Coronary microvascular dysfunction (CMD) has a high prevalence and is associated with adverse clinical outcomes, highlighting the critical importance of early detection. Current research primarily focuses on the microthrombotic/fibrotic stages of CMD. However, the microthrombotic stage already represents a relatively late pathophysiological alteration in CMD. How to achieve precise diagnosis of CMD at an earlier, inflammatory response stage remains a pressing scientific question.
Purpose
To establish a novel molecular imaging strategy capable of accurately identifying the early inflammatory response stage of CMD, thereby enabling its precise diagnosis.
Methods
Based on our preliminary findings identifying Ninjurin1 protein (Ninj1) as a factor upregulated during the early inflammatory stage of CMD, we developed dual-modal targeted microbubbles for detecting this stage by conjugating Ninj1-targeting components with the near-infrared fluorescent material IR780. The general physicochemical properties, particle size, and surface potential of the microbubbles were evaluated. Their stability, targeting capability toward inflamed/damaged endothelial cells in vitro, and contrast-enhanced imaging performance were assessed. Cytotoxicity was also verified. Finally, leveraging the properties of Ninj1-IR780-NBs (abbreviated as T-IR780-NBs) to enhance near-infrared fluorescence and ultrasound imaging signals in vitro, we further applied them in a CMD animal model for validation of dual-modal diagnosis.
Results
Based on the pathological progression, we systematically identified Ninj1 as highly expressed during the early inflammatory stage of CMD via proteomics and subsequently developed dual-modal targeted microbubbles using it as a target for detection. This molecular probe demonstrated good targeting ability toward inflamed/damaged endothelial cells. It also achieved dual-modal (ultrasound/near-infrared) diagnostic efficacy in a mouse model. Furthermore, utilizing the dual-modal imaging technology of T-IR780-NBs, we evaluated the therapeutic efficacy of atorvastatin in treating CMD, providing additional evidence for the targeted diagnostic capability of T-IR780-NBs. The probe exhibited good biocompatibility both in vitro and in vivo.
Conclusion
This study designed and synthesized dual-modal targeted microbubbles (T-IR780-NBs) as an imaging probe for application in diagnosing the early inflammatory stage of CMD. The probe demonstrates favorable biosafety and holds significant potential for early clinical diagnosis of CMD.