ABSTRACT
Objective To evaluate 18F-N- succinimidyl -4-fluorobenzoate (SFB)-Annexin B1 in detectingin vitro andin vivo apoptosis. Methods Anti-Fas antibody was used to induce apoptosis in Jurkat cells. Apoptosis in Jurkat cells was confirmed by flow cytometer (FCM). Unilateral renal ischemia/reperfusion injury was induced by transient (45 min) ligation of the renal artery in the rabbit. The rabbit was then administrated with 18F-SFB-Annexin B1 intravenously 24 h later and then imaged by PET/CT at 10,30,60,90,120 and 240 min postinjection. Apoptosis in kidney was confirmed by terminal deoxynucleotidyl transferase mediated dUTP biotin nick end labeling (TUNEL) assay and HE staining. Results The apoptosis rate induced by anti-Fas antibody was 25.98%(120 min) while that in the control group was only 1.81%. The uptake of 18F-SFB-Annexin B1in apoptosis group was greater than that in the control group. PET/CT images at 240 min showed higher uptake in the ligated kidney than the non-ligated kidney. TUNEL assay and HE staining confirmed great amount apoptotic cells in the ligated kidney. Conclusion 18 F-SFB-Annexin B1may be potentially useful in detecting apoptosis both in vitro and in vivo.
ABSTRACT
Objective To synthesize 16α-[18F]fluoro-17β-estrogen(18F-FES) with high chemical and radiochemical purity using multifunctional radiolabeling module of Explora GN and separation module of Explora LC (Explora GN/LC dual module). Methods Explora GN/LC dual module and one-pot radiochemical process were applied for fully automated synthesis and separation of 18F-FES. The radiochemical purity of 18F-FES was analyzed by HPLC. The saturation binding test of 18F-FES with ER (ER-positive MCF-7 cell line) was applied to examine the biological activity of 18F-FES. Results 18F-FES synthesis procedure took 60 min, with radiochemical yield about 45% and radiochemical purity higher than 98%. The Kd and Bmax of MCF-7 cells with 18F-FES were (2.922±0.619) nmol/L and (4.193±0.360) nmol/L respectively. Conclusions 18F-FES can be automatically synthesized by Explora GN/LC dual module with high chemical purity and radiochemical purity. It would be a potential PET tracer to be used in estrogen-related molecular imaging.