Edispose to chronic kidney disease and end-stage renal disease. Therefore, it would be of clinical value to develop a non-invasive method to detect or assess renal disease.Several animal models have been used to uncover the underlying mechanisms of human lupus nephritis [2]. Indeed, several inbred or hybrid mouse strains develop spontaneous lupus reproducibly. However, the long duration of disease development (usually 6?2 months) hampers their use in the research of the disease [3]. A more rapid model entails subjecting mice to antiglomerular basement membrane antibody (anti-GBM) to induce experimental nephritis [2]. Although the initial insults and clinical presentation may differ in the two diseases, it has been shown that the anti-GBM nephritis model shares common downstream molecular mechanisms with spontaneous lupus nephritis [3,4]. Moreover, the anti-GBM model can be reproducibly induced in mice within a time-frame of 2? weeks. This short time-frame makes it an appealing model to evaluate experimental therapies and imaging techniques. The most commonly used PET probe, 2-deoxy-2-[18F]fluoro-Dglucose (FDG), is a D-glucose analog, in which the hydroxyl group at the 29 position is replaced by 18F, a positron-emitting radioisotope of fluorine. After intracellular uptake, FDG is phosphorylated to FDG-6-phosphate by hexokinase. Being highly negatively charged, FDG-6-phosphate is trapped inside the cells. Because of the 29 position substitution, this metabolite cannot beImaging Assessment of Lupus Nephritismetabolized further in the glycolytic pathway or for glycogen synthesis. Therefore, FDG can be used as a surrogate to track glucose distribution and phosphorylation in vivo by means of PET. In addition to its success in oncology, FDG-PET has also shown promise in clinical evaluation of infection and inflammation because of the elevated glucose consumption in activated inflammatory cells [5?]. For ASP-015K biological activity example, FDG-PET could provide high sensitivity (77?2 ) and specificity (89?00 ) predicative SC1 information for the diagnosis of large-vessel vasculitis in untreated patients with elevated inflammatory markers [8]. Unlike Dglucose, following glomerular filtration, deoxyglucose and FDG are incompletely reabsorbed by the renal tubules after intravenous administration. The unresorbed FDG appears in the renal collecting system and urine [7]. Therefore, dynamic imaging of the kidney permits identification of abnormal kinetics within the renal cortex or the collecting system. We hypothesized that experimental lupus nephritis might alter FDG uptake and/or clearance kinetics. In this study, we evaluated the potential of FDG-PET as a noninvasive imaging technique to longitudinally monitor the renal disease status in an anti-GBM nephritis mouse model.System. All mice were fasted of food overnight before scan. Ten minutes prior to imaging, the animal was anesthetized using 3 isofluorane at room temperature until stable vital signs were established. Once the animal was sedated, it was placed onto the imaging bed under 2 isofluorane anesthesia for the 1317923 duration of imaging. The CT imaging was acquired at 80 kV and 500 mA with a focal spot of 58 mm. After the CT scan, the mouse was injected intravenously with , 37 MBq (100 mCi) of FDG and a 0?60 min dynamic PET was immediately performed. Reconstructed CT and PET images were fused and analyzed using the manufacturer’s software. For PET quantification, the regions of interest (ROI) were selected to include the wh.Edispose to chronic kidney disease and end-stage renal disease. Therefore, it would be of clinical value to develop a non-invasive method to detect or assess renal disease.Several animal models have been used to uncover the underlying mechanisms of human lupus nephritis [2]. Indeed, several inbred or hybrid mouse strains develop spontaneous lupus reproducibly. However, the long duration of disease development (usually 6?2 months) hampers their use in the research of the disease [3]. A more rapid model entails subjecting mice to antiglomerular basement membrane antibody (anti-GBM) to induce experimental nephritis [2]. Although the initial insults and clinical presentation may differ in the two diseases, it has been shown that the anti-GBM nephritis model shares common downstream molecular mechanisms with spontaneous lupus nephritis [3,4]. Moreover, the anti-GBM model can be reproducibly induced in mice within a time-frame of 2? weeks. This short time-frame makes it an appealing model to evaluate experimental therapies and imaging techniques. The most commonly used PET probe, 2-deoxy-2-[18F]fluoro-Dglucose (FDG), is a D-glucose analog, in which the hydroxyl group at the 29 position is replaced by 18F, a positron-emitting radioisotope of fluorine. After intracellular uptake, FDG is phosphorylated to FDG-6-phosphate by hexokinase. Being highly negatively charged, FDG-6-phosphate is trapped inside the cells. Because of the 29 position substitution, this metabolite cannot beImaging Assessment of Lupus Nephritismetabolized further in the glycolytic pathway or for glycogen synthesis. Therefore, FDG can be used as a surrogate to track glucose distribution and phosphorylation in vivo by means of PET. In addition to its success in oncology, FDG-PET has also shown promise in clinical evaluation of infection and inflammation because of the elevated glucose consumption in activated inflammatory cells [5?]. For example, FDG-PET could provide high sensitivity (77?2 ) and specificity (89?00 ) predicative information for the diagnosis of large-vessel vasculitis in untreated patients with elevated inflammatory markers [8]. Unlike Dglucose, following glomerular filtration, deoxyglucose and FDG are incompletely reabsorbed by the renal tubules after intravenous administration. The unresorbed FDG appears in the renal collecting system and urine [7]. Therefore, dynamic imaging of the kidney permits identification of abnormal kinetics within the renal cortex or the collecting system. We hypothesized that experimental lupus nephritis might alter FDG uptake and/or clearance kinetics. In this study, we evaluated the potential of FDG-PET as a noninvasive imaging technique to longitudinally monitor the renal disease status in an anti-GBM nephritis mouse model.System. All mice were fasted of food overnight before scan. Ten minutes prior to imaging, the animal was anesthetized using 3 isofluorane at room temperature until stable vital signs were established. Once the animal was sedated, it was placed onto the imaging bed under 2 isofluorane anesthesia for the 1317923 duration of imaging. The CT imaging was acquired at 80 kV and 500 mA with a focal spot of 58 mm. After the CT scan, the mouse was injected intravenously with , 37 MBq (100 mCi) of FDG and a 0?60 min dynamic PET was immediately performed. Reconstructed CT and PET images were fused and analyzed using the manufacturer’s software. For PET quantification, the regions of interest (ROI) were selected to include the wh.
