Quantification of plaque area and characterization of plaque biochemical composition with atherosclerosis progression in ApoE/LDLR−/− mice by FT-IR imaging

In this work the quantitative determination of atherosclerotic lesion area (ApoE/LDLR−/− mice) by FT-IR imaging is presented and validated by comparison with atherosclerotic lesion area determination by classic Oil Red O staining. Cluster analysis of FT-IR-based measurements in the 2800–3025 cm−1 range allowed for quantitative analysis of the atherosclerosis plaque area, the results of which were highly correlated with those of Oil Red O histological staining (R2 = 0.935). Moreover, a specific class obtained from a second cluster analysis of the aortic cross-section samples at different stages of disease progression (3, 4 and 6 months old) seemed to represent the macrophages (CD68) area within the atherosclerotic plaque.