Molecular imaging of the initial inflammatory response in atherosclerosis: implications for early detection of disease.
Background- We hypothesized that molecular imaging of endothelial cell adhesion molecule expression could noninvasively evaluate prelesion atherogenic phenotype.


RESULTS
Mice deficient for the LDL-receptor and the Apobec-1 editing peptide (DKO mice) were studied as an age-dependent model of atherosclerosis. At 10, 20, and 40 weeks of age, ultrasound molecular imaging of the proximal thoracic aorta was performed with contrast agents targeted to P-selectin and VCAM-1. Atherosclerotic lesion severity and content were assessed by ultrahigh frequency ultrasound, histology, and immunohistochemistry. In wild-type mice at all ages, there was neither aortic thickening nor targeted tracer signal enhancement. In DKO mice, lesions progressed from sparse mild intimal thickening at 10 weeks to widespread severe lesions with luminal encroachment at 40 weeks. Molecular imaging for P-selectin and VCAM-1 demonstrated selective signal enhancement (P<0.01 versus nontargeted agent) at all ages for DKO mice. P-selectin and VCAM-1 signal in DKO mice were greater by 3-fold at 10 weeks, 4- to 6-fold at 20 weeks, and 9- to 10-fold at 40 weeks compared to wild-type mice. En face microscopy demonstrated preferential attachment of targeted microbubbles to regions of lesion formation.


CONCLUSIONS
Noninvasive ultrasound molecular imaging of endothelial activation can detect lesion-prone vascular phenotype before the appearance of obstructive atherosclerotic lesions.
Kaufmann
Beat A
BA
Cardiovascular Division, UHN-62, Oregon Health & Science University, 3181 SW Sam Jackson Park Rd, Portland, OR 97239, USA.
Carr
Chad L
CL
Belcik
J Todd
JT
Xie
Aris
A
Yue
Qi
Q
Chadderdon
Scott
S
Caplan
Evan S
ES
Khangura
Jaspreet
J
Bullens
Sherry
S
Bunting
Stuart
S
Lindner
Jonathan R
JR
D000818:Animals; D001013:Aorta, Thoracic / Q000000981:diagnostic imaging* / Q000276:immunology / Q000378:metabolism*; D050197:Atherosclerosis / Q000000981:diagnostic imaging / Q000276:immunology / Q000378:metabolism; D001783:Blood Flow Velocity; D002448:Cell Adhesion / Q000276:immunology; D004195:Disease Models, Animal; D042241:Early Diagnosis; D004452:Echocardiography; D042783:Endothelial Cells / Q000000981:diagnostic imaging* / Q000276:immunology / Q000378:metabolism*; D034441:Heterogeneous-Nuclear Ribonucleoproteins / Q000235:genetics; D007150:Immunohistochemistry; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D019007:P-Selectin / Q000378:metabolism; D010641:Phenotype; D011973:Receptors, LDL / Q000235:genetics; D019010:Vascular Cell Adhesion Molecule-1 / Q000378:metabolism
D034441:Heterogeneous-Nuclear Ribonucleoproteins; D019007:P-Selectin; D011973:Receptors, LDL; D019010:Vascular Cell Adhesion Molecule-1; C503503:apobec-1 complementation factor, mouse