OBJECTIVE: To evaluate the effectiveness of IL-10 in suppressing 18F-FDG uptake in the inflammatory granuloma of SD rats. METHODS: Eight SD rats were killed, and their blood was collected sterily. After centrifugion, the white blood cells were incubated in PRMI 1640 for 3 days. Then each culture flask of white blood cells was divided into two equal parts. To one group was added 0.2 mL IL-10 solution (0.1 mg/mL); to the control was added with 0.2 mL of 0.9% sodium chloride solution. All cells were then incubated for 120 minutes at 37 degree, after which 18F-FDG (1.85 MBq) was added. Sixty minutes later, the cells were washed twice with PBS and the extent of uptake 18F-FDG determined. In vivo, an inflammatory granuloma was produced by hypodermic injection of rats with a mixture of Freund's complete adjuvant, bovine serum albumin and talcum powder. Each rat was maintained for 8 weeks. Imaging of the inflammatory granulomas was performed using the 18F-FDG signal. IL-10 was injected into SD rats at 10 μg/kg of body weight. Sixty minutes later, 7.4 MBq of 18F-FDG were injected, and, after a further 60 minutes, the rats underwent a PET-CT scan. The region of interest (ROI) of the inflammatory granuloma was delineated and the standard uptake value (SUV) calculated. A second PET-CT scan was done without IL-10 on the next day. The granulomatous tissue underwent pathological examination. RESULTS: In the intro test, the with blood cell uptaking ratio of 18F-FDG was (50.3±6.7)% without IL-10, and (34.6±3.5)% with IL-10(t=8.9, P<0.01). IL-10 suppressed the rat white blood cell uptaking 18F-FDG. In the PET-CT scan, the SUV of ROI on inflammatory granuloma was 1.7±0.4 with IL-10 and 2.1±0.3 without IL-10 (t=20.6, P<0.01). IL-10 suppressed the inflammatory granuloma uptaking 18F-FDG. CONCLUSION IL-10 can suppress the inflammatory granuloma of SD rats uptaking 18F-FDG.
Animals ; Female ; Fluorodeoxyglucose F18 ; pharmacokinetics ; Freund's Adjuvant ; Granuloma ; chemically induced ; metabolism ; Interleukin-10 ; pharmacology ; Lung Diseases ; chemically induced ; metabolism ; Male ; Radiopharmaceuticals ; pharmacokinetics ; Rats ; Serum Albumin, Bovine

Objective:To investigate the efficacy of 99Tc m-pyrophosphate (PYP) SPECT imaging for the differential diagnosis of transthyretin-related cardiac amyloidosis (ATTR-CA) and hypertrophic cardiomyopathy (HCM). Methods:Data of patients who were definitively diagnosed with ATTR-CA (35 patients (28 males, 7 females); age 62.5(58.6, 64.3) years) or HCM (14 patients (13 males, 1 female); age 60.5(57.3, 68.7) years) by extracardiac biopsy and echocardiography in the Second Xiangya Hospital of Central South University between June 2020 and March 2023 were retrospectively analyzed. All patients underwent planar and SPECT imaging 1 h after injection of 370-720 MBq 99Tc m-PYP. Visual scoring was performed (0-1 was negative, 2-3 was positive), and heart-to-contralateral lung uptake ratio (H/CL) was calculated based on planar images. The χ2 test was used to compare the difference in visual scores between ATTR-CA and HCM groups, and the diagnostic efficacy of the visual score was calculated. The H/CL differences between ATTR and HCM groups were compared with Mann-Whitney U test, and the ROC curve was used to analyze the efficacy of H/CL for the differential diagnosis of ATTR-CA and HCM. Results:There were 34 patients with visual scores≥2 and 1 patient with visual score<2 in the ATTR-CA group, 6 patients with visual scores =2 and 8 patients with visual scores <2 in HCM group, and there were significant differences between the 2 groups ( χ2=16.20, P<0.001). The diagnostic sensitivity of the visual score was 97.1%(34/35), and the specificity was 8/14. The H/CL in the ATTR-CA group was significantly higher than that in the HCM group (2.08(1.97, 2.20) vs 1.26 (1.17, 1.35), z=-5.09, P<0.001). The ROC curve analysis suggested that the optimal cut-off value was 1.45 (AUC: 0.980, 95% CI: 0.946-1.000; P<0.001); the sensitivity of H/CL differential diagnosis between HCM and ATTR-CA was 97.1%(34/35), and the specificity was 14/14. Conclusion:99Tc m-PYP SPECT imaging is useful in differentiation of ATTR-CA and HCM, and the optimal cut-off value of H/CL for differential diagnosis of these 2 diseases is 1.45.