Infrared spectroscopic imaging detects chemical modifications in liver fibrosis due to diabetes and disease

Abstract

Abstract:The importance of stroma as a rich diagnostic region in tissue biopsies is growing as there is an increasing understanding that disease processes in multiple organs can affect the composition of adjacent connective tissue regions. This may be especially true in the liver, since this organ's central metabolic role exposes it to multiple disease processes. We use quantum cascade laser infrared spectroscopic imaging to study changes in the chemical status of hepatocytes and fibrotic regions of liver tissue that result from the progression of liver cirrhosis to hepatocellular carcinoma and the potentially confounding effects of diabetes mellitus.

Infrared spectroscopic imaging: Label-free biochemical analysis of stroma and tissue fibrosis

“…Synchrotrons offer high-intensity broadband sources for FT-IR imaging, but are rendered impractical for clinical applications by size constraints (Nasse et al, 2011). Quantum cascade lasers (QCL) provide a new high-intensity source for IR imaging, and these QCL-IR systems have unique features as compared to FT-IR because of their capacity for discrete-frequency imaging (Bird and Rowlette, 2017; Pilling et al, 2017; Sreedhar et al, 2016; Tiwari et al, 2016). …”

“…The spatial information can be correlated to histopathology information from adjacent serial sections, or from the IR sample itself if it is stained following imaging. This dataset can then be analyzed through a diverse array of techniques, by selectively extracting spectra from features of interest within the tissue being studied (Bird and Rowlette, 2017; Martinez-Marin et al, 2016; Sreedhar et al, 2016). …”

“…One such tissue feature that has recently attracted interest in the IR imaging community is areas of stroma or fibrosis (Bird and Rowlette, 2017; Pilling et al, 2017; Sreedhar et al, 2016; Tiwari et al, 2016). Early IR investigations of tissue samples tended to focus on cancers and other disease processes that centered on epithelia and parenchyma.…”

“…As diabetes mellitus is a disease with metabolic implications that lead to changes in multiple organ systems, it is not surprising that some of these alterations are found in liver fibrosis. QCL-IR data has demonstrated differences between fibrotic spectra in liver samples from diabetic and nondiabetic patients spanning the range of hepatic pathology from cirrhosis to hepatocellular carcinoma (Sreedhar et al, 2016). In the context of renal pathology, FT-IR has been able to accurately detect and classify fibrosis, which is a hallmark of kidney damage (Vuiblet et al, 2015).…”

Infrared spectroscopy as a new tool for studying single living cells: Is there a niche?

“…Owing to the large number of spectral data collected in a single map, specific software based on multivariate statistical analysis have been developed to highlight spectral similarities and differences in a simple readout format [36,64]. Hence, subtle changes caused by various biochemical processes, such as the occurrence of specific pathologies, benign and malignant ones, or by various cellular differentiation steps, can be detected [27,29,30,40,61,63]. Cells are dynamic systems, changing their macromolecular composition during the cell cycle.…”