In vivo Imaging Method to Distinguish Acute and Chronic Inflammation |
| |
Authors: | Jen-Chieh Tseng Andrew L Kung |
| |
Institution: | 1.Lurie Family Imaging Center, Dana-Farber Cancer Institute, Harvard Medical School;2.Division of Pediatric Hematology/Oncology/Stem Cell Transplantation, Columbia University Medical Center |
| |
Abstract: | Inflammation is a fundamental aspect of many human diseases. In this video report, we demonstrate non-invasive bioluminescence imaging techniques that distinguish acute and chronic inflammation in mouse models. With tissue damage or pathogen invasion, neutrophils are the first line of defense, playing a major role in mediating the acute inflammatory response. As the inflammatory reaction progresses, circulating monocytes gradually migrate into the site of injury and differentiate into mature macrophages, which mediate chronic inflammation and promote tissue repair by removing tissue debris and producing anti-inflammatory cytokines. Intraperitoneal injection of luminol (5-amino-2,3-dihydro-1,4-phthalazinedione, sodium salt) enables detection of acute inflammation largely mediated by tissue-infiltrating neutrophils. Luminol specifically reacts with the superoxide generated within the phagosomes of neutrophils since bioluminescence results from a myeloperoxidase (MPO) mediated reaction. Lucigenin (bis-N-methylacridinium nitrate) also reacts with superoxide in order to generate bioluminescence. However, lucigenin bioluminescence is independent of MPO and it solely relies on phagocyte NADPH oxidase (Phox) in macrophages during chronic inflammation. Together, luminol and lucigenin allow non-invasive visualization and longitudinal assessment of different phagocyte populations across both acute and chronic inflammatory phases. Given the important role of inflammation in a variety of human diseases, we believe this non-invasive imaging method can help investigate the differential roles of neutrophils and macrophages in a variety of pathological conditions. |
| |
Keywords: | Immunology Issue 78 Infection Medicine Cellular Biology Molecular Biology Biomedical Engineering Anatomy Physiology Cancer Biology Stem Cell Biology Inflammation Phagocytes Phagocyte Superoxides Molecular Imaging chemiluminescence in vivo imaging superoxide bioluminescence chronic inflammation acute inflammation phagocytes cells imaging animal model |
|
|