Proteomic and genomic approaches provide increasingly comprehensive snapshots of biological networks. Often however, the molecular players in these networks are temporally and spatially very dynamic, and their precise mapping along the time-space continuum can become cost prohibitive or be sample limited. Noninvasive molecular imaging has the potential to longitudinally interrogate specific cellular and molecular hubs in vivo. Until recently, most macroscopic imaging techniques have been limited to display only one molecular player at any given time. We have developed quantitative 4-channel FMT-CT (Q4-FMT) to simultaneously map small """"""""clusters"""""""" of biological targets in vivo. The technology is based on reconstruction of optical photons in transillumination geometry and fusion of 3D fluorescence data-sets with anatomic CT. We have recently adapted reconstruction algorithms to different wavelengths, effectively yielding 4 separate read-out channels. Here we propose to biologically validate and apply Q4-FMT for non-invasive interrogation of a biomarker network in wound healing models following myocardial infarction. We will use a set of imaging agents that interrogate key wound healing biomarkers: a) fluorescent nanoparticles to probe phagocytic activity, b) activatable optical agents to measure protease activity, c) tagged transglutaminase peptide substrates to report on extracellular matrix crosslinking, and d) integrin-targeted nanoparticles reporting on angiogenesis. First, systematic phantom experiments will address system performance in all channels, channel crosstalk, sensitivity, and precision of fluorochrome quantitation and image fusion. Second, in vivo imaging results will be quantitated and justaxposed to results from traditional, accepted gold standards such as flow cytometric analysis of cell suspensions from infarcts, genomic and proteomic data, and to immunoreactive histology. Finally, we will use Q4- FMT to assess therapeutic implications of monocyte subset recruitment and function on the above biomarkers during myocardial infarction in a mouse model of coronary ligation. This is important because timely detection of impaired healing would allow to intervene therapeutically to prevent heart failure. Using lipidoid-delivered siRNA we will silence CCR2. This experimental therapy targets the chemokine receptor that governs recruitment of inflammatory Ly-6Chi but not that of reparative Ly6Clo monocytes, while we will image infarct healing serially with Q4-FMT. We hypothesize that effects of modulating inflammatory monocyte recruitment can be monitored by Q4-FMT in realtime, enhances myocardial repair, and provides novel therapeutic strategies for infarct patients.

Public Health Relevance

Our goal is to establish and validate Q4-FMT, which combines simultaneous 4-channel fluorescence molecular tomography with anatomical CT imaging, allowing to image a """"""""cluster"""""""" of biomarkers simultaneously. We propose to validate Q4-FMT against established ex vivo gold standards and to apply it to study tissue repair after myocardial infarction to identify novel therapeutic targets for enhancement of myocardial repair and prevention of heart failure.

Agency
National Institute of Health (NIH)
Institute
National Heart, Lung, and Blood Institute (NHLBI)
Type
Research Project (R01)
Project #
5R01HL096576-02
Application #
7897942
Study Section
Special Emphasis Panel (ZRG1-MEDI-A (09))
Program Officer
Danthi, Narasimhan
Project Start
2009-08-01
Project End
2013-07-31
Budget Start
2010-08-01
Budget End
2011-07-31
Support Year
2
Fiscal Year
2010
Total Cost
$406,296
Indirect Cost
Name
Massachusetts General Hospital
Department
Type
DUNS #
073130411
City
Boston
State
MA
Country
United States
Zip Code
02199
Hulsmans, Maarten; Sager, Hendrik B; Roh, Jason D et al. (2018) Cardiac macrophages promote diastolic dysfunction. J Exp Med 215:423-440
Honold, Lisa; Nahrendorf, Matthias (2018) Resident and Monocyte-Derived Macrophages in Cardiovascular Disease. Circ Res 122:113-127
Keliher, Edmund J; Ye, Yu-Xiang; Wojtkiewicz, Gregory R et al. (2017) Polyglucose nanoparticles with renal elimination and macrophage avidity facilitate PET imaging in ischaemic heart disease. Nat Commun 8:14064
Vandoorne, Katrien; Nahrendorf, Matthias (2017) Multiparametric Imaging of Organ System Interfaces. Circ Cardiovasc Imaging 10:
Hulsmans, Maarten; Clauss, Sebastian; Xiao, Ling et al. (2017) Macrophages Facilitate Electrical Conduction in the Heart. Cell 169:510-522.e20
Sager, Hendrik B; Hulsmans, Maarten; Lavine, Kory J et al. (2016) Proliferation and Recruitment Contribute to Myocardial Macrophage Expansion in Chronic Heart Failure. Circ Res 119:853-64
Dutta, Partha; Hoyer, Friedrich Felix; Sun, Yuan et al. (2016) E-Selectin Inhibition Mitigates Splenic HSC Activation and Myelopoiesis in Hypercholesterolemic Mice With Myocardial Infarction. Arterioscler Thromb Vasc Biol 36:1802-8
Hulsmans, Maarten; Sam, Flora; Nahrendorf, Matthias (2016) Monocyte and macrophage contributions to cardiac remodeling. J Mol Cell Cardiol 93:149-55
Sager, Hendrik B; Dutta, Partha; Dahlman, James E et al. (2016) RNAi targeting multiple cell adhesion molecules reduces immune cell recruitment and vascular inflammation after myocardial infarction. Sci Transl Med 8:342ra80
Swirski, Filip K; Nahrendorf, Matthias (2016) Bone Marrow Takes Center Stage in Cardiovascular Disease. Circ Res 119:701-3

Showing the most recent 10 out of 62 publications