Abstract 17789: Comprehensive Optical Imaging of Macrophages Associated With Intraplaque Hemorrhage Using the Integrated Dual Modal OCT-NIRF Structural-Molecular Imaging
Introduction: Intraplaque hemorrhages (IPHs) are associated with rupture-prone plaques. Within IPHs, macrophages differentiate into a specific phenotype characterized by the expression of mannose receptors. The purpose of this study was to investigate the feasibility of intravascular optical coherence tomography (OCT)-near infrared fluorescence (NIRF) structural-molecular imaging combined with a NIRF probe targeting mannose receptors to estimate IPHs in vivo.
Methods and Results: IPH was induced by injecting centrifuged autologous erythrocytes through a micro-infusion catheter into rabbit aortic plaques. Normal chow diet was continued for an additional 6 weeks for macrophage differentiation. 48 hours after intravenous injection of our newly synthesized NIRF labeled nanoprobe (ex/em 750/773 nm) targeting macrophage mannose receptors at a dose of 10 mg/kg, OCT-NIRF imaging demonstrated highly enhanced NIRF signals in IPH lesions characterized by black-dotted neovessels surrounded with heterogenous OCT signals (asterisk), suggesting the association of mannose receptor positive macrophages with intraplaque hemorrhagic transformation (Figure). FM and histologic findings from the corresponding sister sections corroborated the in vivo imagings, which demonstrated the co-localization of NIRF signals with macrophage mannose receptors and hemorrhagic compositions.
Conclusions: OCT-NIRF imaging with a NIRF probe targeting mannose receptors could provide a promising novel strategy to estimate IPH-associated macrophages and detect high-risk plaques.
Author Disclosures: J. Lee: None. M. Lee: None. T. Kim: None. J. Song: None. D. Oh: None. K. Park: None. W. Oh: None. H. Yoo: None. J. Kim: None.
- © 2015 by American Heart Association, Inc.