Magnetic Particle Imaging in Vascular Imaging, Immunotherapy, Cell Tracking, and Noninvasive Diagnosis

Figure 11

(a) Maximum intensity projection (MIP) of 3D MPI using anti-Ly6G antibody SPIOs (neutrophil targeting) compared to an X-ray CT image of a mouse. The antibody tracers of MPI are distributed in bone marrow of the skull, limbs, pelvic bones, and reticuloendothelial organs of the liver and spleen. The antibody tracers also accumulate in the kidneys. This clearance pattern is observed in antibody-based therapeutics, which is atypical for MPI tracers to accumulate in the kidneys [3, 148]. MPI can thus be tremendously valuable for tracking antibody therapeutics with negligible renal toxicity, often observed in radioactive antibody tracers. (b) Anti-Ly6G antibody MPI tracer imaging of inflammation/infection in a murine model of bacterial myositis using lipopolysaccharide (LPS) on the right flank. MPI showed a CNR of ~8-12 in the inflammatory site versus the contralateral side (data overlayed on a mouse anatomical outline, with the liver signal segmented through apodization) [23, 138, 148].

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