Longitudinal Tracking of Recipient Macrophages in a Rat Chronic Cardiac Allograft Rejection Model With Noninvasive Magnetic Resonance Imaging Using Micrometer-Sized Paramagnetic Iron Oxide Particles

• DOI: 10.1161/circulationaha.107.746354
• Publication Date: 2008-07-01T00:54:19Z
• Authors: Qing Ye; Yijen L. Wu; Lesley M. Foley; T. Kevin Hitchens; Danielle F. Eytan; Haval Shirwan; Chien Ho
• Keywords: Micrometer; Cardiac magnetic resonance; Tracking (education)

Long-term survival of heart transplants is hampered by chronic rejection (CR). Studies indicate the involvement host macrophages in development CR; however, precise role these cells CR unclear. Thus, it important to develop noninvasive techniques serially monitor movement and distribution recipient cardiac allograft vivo.We have employed a rat heterotopic working-heart model for magnetic resonance imaging experiment. Twenty-one (PVG.1U-->PVG.R8) 9 isograft (PVG.R8-->PVG.R8) transplantations were performed. Recipient are labeled via intravenous injection micron-sized paramagnetic iron oxide particles (0.9 microm diameter) at dose 4.5 mg Fe per 1 day before transplantation. Serial vivo images acquired up 16 weeks. The migration our model, which evident 3 weeks most extensive after transplantation, can be assessed with use >100 days single injection. location confirmed microscopy histology.This approach may improve understanding immune involved management Moreover, this study demonstrates feasibility noninvasively observing individual targeted over long time periods serial imaging.