日本血吸虫SjFABPc重组质粒裸DNA免疫小鼠的研究

A STUDY ON DNA-BASED IMMUNIZATION WITH EUKARYOTIC EXPRESSION RECOMBINANT PLASMID ENCODING GENE OF FATTY ACID-BINDING PROTEIN FROM SCHISTOSOMA JAPONICUM IN BALB/C MICE

目的 裸 DNA重组质粒 p CD- Sj FABPc经肌肉注射、皮内途径免疫小鼠 ,观察其在小鼠体内所诱生的细胞及体液免疫应答。方法 碱裂解法大量制备重组质粒 p CD- Sj F加强免疫 1次。分别于末次免疫后的第 2 0、5 0、6 5天共 3次用 MTT法检测脾脏 T淋巴细胞增殖与 NK细胞活性 ,并用双夹心 EL ISA测定血清细胞因子 IL- 2、IFN- γ及 IL- 10含量 ;EL ISA法测定免疫鼠血清 Ig G抗体。结果 MTT法 3次动态测定 NK细胞及脾淋巴细胞增殖 ,不同途径 p CD- Sj FABPc质粒免疫组均明显高于生理盐水 (NS)及空质粒对照组 (P<0 .0 5 )。不同途径 p CD- Sj FABPc免疫组 IL - 2血清含量的平均值均显著高于 NS与空质粒对照组 (P<0 .0 1) ;IFN- γ的值也均显著高于 NS对照组 (P<0 .0 1) ,但与空质粒对照组的差异无显著性 (P>0 .0 5 ) ;不同途径 p CD- Sj FABPc免疫组 IL- 10值与 NS及空质粒对照组的比较则差异无显著性 (P>0 .0 5 )。重组质粒免疫后 2 0 d、5 0 d检测 ,抗体滴度无明显增高 ;6 5 d检测 ,p CD- Sj FABPc免疫组 A值明显高于对照组 (P<0 .0 1)。结论 重组质粒免疫后可诱导小鼠产生有效的细胞与体液免疫应答 。

Objective Evaluating the cellular and humoral immune responses to both intramuscular and intracutaneous immunizations with DNA-bsaed plasmid pCD-SjFABPc in mice. Methods Large scale preparations of plasmids DNA were performed by alkaline lysis, and mice were inoculated DNA plasmids by intramuscular and intracutaneous injections at the dosage of 100 μg each mouse respectively. A booster vaccine was given with the same dosage after two weeks. Control groups were injected with pcDNA3 blank plasmid and normal saline respectively. Twenty, fifty and sixty-five days after the second booster injection, following tests were carried out 3 times separately. The splenocytes from experimental mice were used to detect the killing activity of NK cells and the proliferation activity of T lymphcytes by means of MTT assay, and the serum from the mice were used to detect the cytokines, IFN-γ,IL-2 and IL-10 by means of sandwich ABC-ELISA, as well as the titer of IgG antibody by ELISA. Results The activities of NK and proliferation of spleen T lymph cells by 3 times of MTT assay in both intramuscular and intracutaneous injection in pCD-SjFABPc groups were higher than those in control ones (P<0 05). The average value of IL-2 was significantly higher in the vaccinated group than that in the control groups (P<0 01). The average value of IFN-γ was also higher in the vaccinated group than that in NS control group (P<0 01), but there was no significant difference compared with pcDNA3 control group (P>0 05). There was no significant changes of the value of IL-10 among these groups (P>0 05). Twenty and fifty days after immunization, the antibody detectings were negative. After 65 days of immuniza-tion, the titer of IgG antibody in both pCD-SjFABPc groups were significantly higher than that in control ones (P<0 01) . Conclusion Both cellular and humoral immuno-response could be elicited in mice vaccinated with recombinant plasmid, as well as products of the same type of cytokines.