Identification of cholesterol crystals in plaques of atherosclerotic mice using hyperspectral CARS imaging

Study of the Development of the Mouse Thoracic Aorta Three-Dimensional Macromolecular Structure using Two-Photon Microscopy

“…There have been many different approaches used in preparing vessels for ex vivo microscopy reported in the literature. Some have included mounting variably sized vessel segments into a perfusion chamber (Megens et al 2007a;Megens et al 2007b), fresh and/or formalinfixed tissue preparations mounted between a glass slide and a coverslip (Kwon et al 2008;Lee et al 2009;Kim et al 2010, Lim et al 2010, Lim et al 2011Suhalim et al 2012), as well as agar gel-infused vascular casts that are segmented into thinly sliced molds and mounted on a glass slide (van Zandvoort et al 2004;Megens et al 2007a;Megens et al 2008;Le et al 2010). In vivo approaches have also been described but these are with the addition of mechanical techniques to help minimize motion artifact.…”

Accumulating advantages, reducing limitations: Multimodal nonlinear imaging in biomedical sciences – The synergy of multiple contrast mechanisms

“…Hence, a variety of techniques for multispectral data analysis have been applied to spectral CRS and fluorescence data. Principal component analysis (PCA) known from linear Raman spectroscopy has been applied to spectral CARS data to visualize differences in the lipid distribution in meibomian glands [46], and to identify cholesterol crystals in both SRS and CARS spectral data [37,47]. Even more sophisticated methods are required to extract the Raman spectrum from multiplex CARS data, e.g., the maximum entropy method or the Kramers Kronig relations [48][49][50].…”

Danger Signaling in Atherosclerosis

“…Phagocytosis of cholesterol crystals by murine and human macrophages results in NLRP3 inflammasome activation and subsequent secretion of large amounts of IL-1β. 87,131,132 Notably, atherogenesis was decreased in LDLR −/− mice transplanted with bone marrow deficient in NLRP3, apoptosis-associated speck-like protein containing a caspase recruitment domains (CARD), or IL-1α/β. 87 Together, these studies show that cholesterol in a crystalline state represents a danger signal that is recognized by innate immune cells leading to the induction of inflammatory responses.…”