Imaging Inflammation

Peters AM, Danpure HJ, Osman S, Hawker RJ, Henderson BL, Hodgson HJ, Kelly JD, Neirinckx RD, Lavender JP (1986) Clinical experience with " Tc-HMPAO for labeling leukocytes and imaging inflammation. Lancet 25 946-949... 

Cytokines, hormone-like proteins, enable cells of the immune system to communicate. Signore et al. (1992) have shown the feasibility of imaging infectious foci with radioiodinated cytokines. I-IL-1 has been studied to image inflammation in patients with rheumatoid arthritis. It allowed visualization of inflamed joints, but without speciflc flxation (Barrera et al., 2000). I-IL-8, radioiodinated by the Bolton-Hunter method, shows a hyperfixation in the rabbit, localized in the infectious foci, obtained by injection of Escherichia coli in the muscle (Van der Laken et al, 2000). 

Selective AR agonists are undergoing clinical trials for cardiac arrhythmias and pain (Ai) cardiac imaging and inflammation (A2a) colon cancer, rheumatoid arthritis, psoriasis, and dry eye (A3). Selective AR antagonists are either in or advancing toward clinical trials for kidney disorders (Ax) Parkinson s disease (A2a) diabetes and asthma (A2B) cancer and glaucoma (A3). 

Endoscopic approaches are typically used and may include colonoscopy, proctosigmoidoscopy, or possibly upper GI endoscopy in patients with suspected CD. Endoscopy is useful for determining the disease distribution, pattern and depth of inflammation, and to obtain mucosal biopsy specimens. Supplemental information from imaging procedures, such as computed tomography (CT), abdominal x-ray, abdominal ultrasound, or intestinal barium studies may provide evidence of complications such as obstruction, abscess, perforation, or colonic dilation.3... 

Nuclear medicine scans Method of body imaging that uses a radioactive tracer material (e.g., technetium and gallium) to produce body images. For example, bone scans detect uptake and cellular activity in areas of inflammation. 

Gallium is non-essential, but on account of the similarity between Ga3+ and Fe3+ it binds to iron transport and storage proteins such as transferrin and ferritin. The radioactive isotope of gallium, 67Ga, concentrates to a large extent in many tumours and at sites of inflammation and infection, and since many tumours overexpress the transferrin receptor it can be used for tumour imaging. 

Molecular imaging may potentially address not only the pathophysiology of ischemia but also vascular inflammation causing rupture of atherosclerotic plaques before major ischemic events. Initial approaches have used imaging of "indium radiolabeled monocytes [150], upregulated metallo-proteinases [151], and imaging of apoptosis in atherosclerotic lesions [152]. However, none have evolved into clinically useful tests. 

Narula J, Verjans J, Zaret BL. Radionuclide approach to imaging of inflammation in atheroma for the detection of lesions vulnerable to rupture. In Zaret BL, Beller G. Clinical nuclear cardiology state of the art and future directions. 3rd ed. Philadelphia Mosby, pp 659-671,2005... 

Diagnostic imaging for infection/inflammation in bone of patients with osteomyelitis... 

Atherosclerosis The imaging of atherosclerosis with [ F]FDG PET was advanced and recent studies in rabbits showed that the tracer accumulated in macrophage-rich atherosclerotic plaques. It was assumed that the vascular macrophage activity can be quantified by p FlFDO PET [189]. Further studies in rabbits demonstrated that this imaging modality is useful for the clinical evaluation of therapeutic effects of drugs as well as for the development of new drugs that can reduce and inhibit inflammation of vulnerable plaques [190]. 

J.H. Rudd, E.A. Warburton, T.D. Fryer, H.A. Jones, J.C. Clark, N. Antoun, P. Johnstrom, A.P. Davenport, P.J. Kirkpatrick, B.N. Arch, J.D. Pickard, P.L. Weissberg, Imaging atherosclerotic plaque inflammation with [ F]-fluorodeoxy-glucose positron emission tomography. Circulation 105 (2002) 2708-2711. 

J.H.F. Rudd, K.S. Myers, S. Bansilal, J. Machac, A. Rafique, M. Farkouh, V. Fuster, Z.A. Fayad, Fluorodeoxyglucose positron emission tomography imaging of atherosclerotic plaque inflammation is highly reproducible Implications for atherosclerosis therapy trials, J. Am. Coll. Cardiol. 50 (2007) 892-896. 

Low levels of LA are found in the sebum of acne sufferers,200 and levels appear inversely related to sebum secretion rate.201 It has been hypothesized that this local EFA deficiency may lead to the follicular hyperkeratosis and occlusion of acne, and that an increased supply of linoleate might possibly ameliorate the condition.202 In support of this, digital image analysis revealed that topical application of LA over a one month period reduced the size of microcomedones.203 Decreased levels of LA may also contribute to acne inflammation by failing to inhibit phagocytosis and ROS generation by neutrophils.204... 

SPIOs are used for gastrointestinal tract, liver, and spleen imaging and take advantage of the natural clearance of the RES, the transit time through the gut or preferential uptake by specific cells. The most promising uses of SPIOs are to improve the sensitivity of detection and localization of primary and metastatic brain tumors, inflammation and ischemia (insufficient supply of blood to an organ) [154-156],... 

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