Figure 4. 18FDG uptake is linked to presence of CD11b+ monocytes/macrophages (Mφ).
(A) Experimental set up. Mice were injected, and activity in infarct was assessed by scintillation counting. Thereafter, CD11b+ monocytes/macrophages were isolated from the same infarct tissue by positive selection with antibodies coupled to magnetic beads. (B) To express gamma counts normalized to cellular weight, mean cell diameter was measured by intravital microscopy (IVM). The mean monocytic diameter was then used to calculate cell volume and weight. Scale bar indicates 15μm. (C) Activity of monocytes/macrophages and the tissue from which they were isolated. (D) Counts per minute (CPM) for cell types isolated from infarct tissue (EC: endothelial cells). (E) PET/MRI on day 5 after MI, followed by ex vivo counting. Mφ depl: monocyte/macrophage depletion with clodronate liposomes. (F) FACS enumeration (upper panels) and immunohistochemical staining (lower panels) of monocytes/macrophages in infarcts. Mean±SEM. *P<0.05. Scale bar indicates 30μm.