Multimodality molecular imaging identifies proteolytic and osteogenic activities in early aortic valve disease.

Background: Visualizing early changes in valvular cell functions in vivo may predict the future risk and identify therapeutic targets for prevention of aortic valve stenosis.

Methods And Results: To test the hypotheses that (1) aortic stenosis shares a similar pathogenesis to atherosclerosis and (2) molecular imaging can detect early changes in aortic valve disease, we used in vivo a panel of near-infrared fluorescence imaging agents to map endothelial cells, macrophages, proteolysis, and osteogenesis in aortic valves of hypercholesterolemic apolipoprotein E-deficient mice (30 weeks old, n=30). Apolipoprotein E-deficient mice with no probe injection (n=10) and wild-type mice (n=10) served as controls.

Chemokine CXCL10 promotes atherogenesis by modulating the local balance of effector and regulatory T cells.

Background: Studies to define the overall contribution of lymphocytes to lesion formation in atherosclerosis-susceptible mice have demonstrated relatively subtle effects; the use of lymphocyte-deficient mice, however, compromises both the effector and regulatory arms of the immune system. Here, we tested the hypothesis that deletion of CXCL10 (IP-10), a chemokine specific for effector T cells that has been localized within atherosclerotic lesions, would significantly inhibit atherogenesis.

Methods And Results: Compound deficient Apoe(-/-)/Cxcl10(-/-) mice fed a Western-style diet for either 6 or 12 weeks demonstrated significant reductions in atherogenesis as compared with Apoe(-/-) controls, as assessed by both aortic en face and cross-sectional analyses.