钠碘转运体应用于人下咽鳞癌显像和诊断的可行性研究

Study on feasibility of using sodium/iodine symporter for imaging and diagnosis of human hypopharyngeal squamous cell carcinoma

目的:探讨杆状病毒介导的人钠碘转运体(human sodium/iodine symporter,hNIS)应用于人下咽鳞癌显像和诊断的可行性。方法:通过Bac-to-Bac杆状病毒表达系统包装分别含GFP和hNIS的重组杆状病毒(Bac-GFP和Bac-hNIS),用流式细胞仪检测Bac-GFP对人下咽癌细胞(FaDu)的转导效率,并用间接免疫荧光检测hNIS在FaDu细胞中的定位。进行hNIS介导的碘摄取、动态摄碘和NaClO4碘摄取抑制实验,并检测共转染了Bac-GFP和Bac-hNIS的FaDu细胞中的荧光强度和放射性计数。结果:在丁酸钠的作用下,Bac-GFP在感染复数为400时,对FaDu细胞的转导效率可达95.16%;hNIS可准确定位于FaDu细胞膜上,具备摄碘功能;放射性计数与荧光强度间呈线性正相关(相关系数为0.943),可通过放射性计数的变化来反映荧光强度的变化。结论:杆状病毒对FaDu细胞具有高转导效率,Bac-hNIS可有效介导FaDu细胞的碘摄取,hNIS可用于人下咽鳞癌的显像和诊断。

Objective： To investigate the feasibility of using baculovirus-mediated human sodium/iodine symporter （hNIS） for imaging and diagnosis of human hypopharyngeal squamous cell carcinoma. Methods： Two recombinant bacu loviruses expressing green fluorescent protein （GFP） and hNIS, respectively, were constructed according to the Bac-to-Bac Baculovirus Expression System package. The transduction efficiency of human hypopharyngeal cancer cells （FaDu cells） by Bac-GTP was determined by flow eytometry, and the loealizaton of hNIS on FaDu cells was determined by indirect im- munofluorescence. The iodine uptake, dynamic iodine uptake and inhibition of iodine uptake by NaCIO were examined. The radioactivity and fluorescence intensity in Bac-GFP and Bac-hNIS co-infected FaDu cells were measured. Results： Bae-GFP and Bac-hNIS were constructed successfully. The transduction efficiency of FaDu cells by Bac-GFP at MOI （multiplicity of infection） 400 with sodium butyrate could reach 95.16%. NIS protein could be localized accurately on FaDu cell membranes and performing its function of iodine uptake. The correlation coefficient between radioactivity and fluorescence intensity was 0.943, a linear positive correlation, and the change in level of radioactivity could be used to es- timate the change in fluorescence intensity. Conclusions： Baculovirus could efficiently transduce FaDu cells. Iodine up- take by FaDu cells could be mediated effectively by Bae-hNIS, and NIS could be used for imaging and diagnosis of human hypopharyngeal squamous cell carcinoma.