Abstract：
Due to the continuous rise in global incidence and severity of invasive fungal infections (IFIs), particularly among immunocompromised and immunodeficient patients, there is an urgent demand for swift and accurate fungal pathogen diagnosis. Therefore, the need for fungal-specific positron emission tomography (PET) imaging agents that can detect the infection in the early stages is increasing. Cellobiose, a disaccharide, is readily metabolized by fungal pathogens such as Aspergillus species. Recently, our group reported fluorine-18 labeled cellobiose, 2-deoxy-2-[18F]fluorocellobiose ([18F]FCB), for specific imaging of Aspergillus infection. The positive imaging findings with very low background signal on delayed imaging make this ligand a promising fungal-specific imaging ligand. Inspired by this result, the decision was made to automate the radiolabeling procedure for better reproducibility and to facilitate clinical translation. A Trasis AllInOne (Trasis AIO) automated module was used for this purpose. The reagent vials contain commercially available 2-deoxy-2-[18F]fluoroglucose ([18F]FDG), glucose-1-phosphate, and enzyme (cellobiose phosphorylase). A Sep-Pak cartridge was used to purify the tracer. The overall radiochemical yield was 50%-70% (n = 6, decay corrected) in 75-min synthesis time with a radiochemical purity of > 98%. This is a highly reliable protocol to produce current good manufacturing practice (cGMP)-compliant [18F]FCB for clinical PET imaging.
摘要：
由于侵袭性真菌感染（IFIs）的全球发病率和严重程度的持续上升，特别是在免疫受损和免疫缺陷患者中，迫切需要快速准确的真菌病原体诊断。因此,对真菌特异性正电子发射断层扫描(PET)显像剂的需求正在增加,这些显像剂可以在早期阶段检测感染.纤维二糖,一种二糖，容易被真菌病原体如曲霉属物种代谢。最近,我们小组报告了氟-18标记的纤维二糖，2-脱氧-2-[18F]氟二糖（[18F]FCB），用于曲霉菌感染的特异性成像。在延迟成像时具有非常低的背景信号的阳性成像发现使该配体成为有前途的真菌特异性成像配体。受到这个结果的启发，我们决定将放射性标记程序自动化,以获得更好的可重复性并促进临床翻译.为此使用TrasisAllInOne(TrasisAIO)自动模块。试剂瓶含有市售的2-脱氧-2-[18F]氟葡萄糖([18F]FDG)，葡萄糖-1-磷酸，和酶(纤维二糖磷酸化酶)。使用Sep-Pak筒纯化示踪剂。在75分钟的合成时间内,总放射化学产率为50%-70%(n=6,衰变校正),放射化学纯度>98%。这是高度可靠的方案,以产生用于临床PET成像的符合当前良好生产规范(cGMP)的[18F]FCB。
