日本血吸虫双价DNA疫苗体内外表达及持续时间的初步研究

Preliminary studies on the expression of bivalent DNA vaccine against Schistosoma japonicum in vitro/vivo and lasting time

目的观察日本血吸虫双价DNA疫苗在体内外表达及体内表达的持续时间。方法将构建的共表达日本血吸虫双价核酸疫苗pVIVO2-SjFABP/Sj23瞬时转染HEK-293细胞,通过逆转录(RT-PCR)和间接免疫荧光试验(IFAT)检测真核细胞中SjFABP和Sj23基因及蛋白的表达。质粒经股四头肌注射免疫BALB/c小鼠12只,每月眼眶采血,并活体灌流小鼠2只,IFAT检测重组蛋白的原位表达,Westernblot法检测血清中特异性抗体,持续观察6个月。结果RT-PCR和IFAT证明质粒pVIVO2-SjFABP/Sj23能在体外表达。免疫后连续6个月,IFAT均检测到小鼠骨骼肌注射部位重组蛋白的原位表达,但Westernblot未检测到血清中特异性抗体的存在。结论日本血吸虫双价DNA疫苗在HEK-293细胞和小鼠骨骼肌中均能够正确地表达,体内表达持续时间至少在6个月以上。

Objective To study the expression of bivalent DNA vaccine against Schistosoma japonicum in vitro/vivo and lasting time in vivo. Methods The bivalent DNA pVIVO2-SjFABP/ Sj23 was transfected transiently into the human embryonic kidney cells of the line 293. RT-PCR was used to detect the expressions of SjFABP and Sj23 mRNA in the 293 cells. Indirect immunofluorescence antibody test （IFAT） was used to detect the expressions of SjFABP and Sj23 proteins. Twelve BALB/c mice were inoculated with pVIVO2-SjFABP/Sj23 via intramuscular injection. Two blood samples were collected from eye sockets and two mice were vivi-perfused each month. This work lasted for 6 months. IFAT was used to detect the expression of proteins in skeletal muscle. Western-blot was used to detect the serum IgG level. Results RT-PCR and IFAT showed the expressions of SjFABP and Sj23 in the HEK-293 cells. IFAT showed SjFABP/Sj23 was present in vivo at least for 6 months. Special IgG was not detected by Western blot. Conclusions pVIVO2-SjFABP/Sj23, bivalent DNA vaccine, could express correctly in vitro/vivo, and lasts for 6 months at least in vivo.