重组弓形虫磷酸甘油酸变位酶2联合白细胞介素-2或干扰素γ诱导小鼠的脾淋巴细胞免疫应答

Splenic lymphocyte immune response induced by recombinant Toxoplasma gondii phosphoglycerate mutase 2 in combination with interleukin-2 or interferon γ in mice

目的观察重组弓形虫磷酸甘油酸变位酶2(Recombinant Toxoplasma gondii phosphoglycerate mutase 2,rTgPGAM2)联合白细胞介素-2(Interleukin-2,IL-2)或干扰素γ(Interferonγ,IFNγ)滴鼻免疫小鼠诱导的脾淋巴细胞免疫应答,探讨IL-2和IFNγ的佐剂效应。方法将48只BALB/c小鼠随机均分为6组:rTgPGAM2组(30μg)、IL-2组(500 IU)、IFNγ组(1 000 IU)、rTgPGAM2(30μg)+IL-2(500 IU)组和rTgPGAM2(30μg)+IFNγ(1 000 IU)组和对照组(20μl PBS),免疫途径均为滴鼻免疫,共免疫3次。末次免疫后第14天,颈椎脱臼处死小鼠,CCK-8法检测各组小鼠脾淋巴细胞增殖活性,ELISA法检测脾淋巴细胞培养上清中IL-2、IFNγ、IL-4和IL-10水平。结果经rTgPGAM2刺激后,与对照组比较,各免疫组小鼠脾淋巴细胞刺激指数(Stimulation index,SI)均显著高于对照组(P<0.05或P<0.01),rTgPGAM2联合IL-2或IFNγ组显著高于rTgPGAM2组(P<0.01或P<0.05);经ConA刺激后,仅IL-2组SI显著高于对照组(P<0.01)。各免疫组小鼠脾淋巴细胞培养上清中IL-2和IFNγ含量均显著高于对照组(P<0.05或P<0.01),rTgPGAM2联合IL-2或IFNγ组显著高于rTgPGAM2组(P<0.01或P<0.05);rTgPGAM2组及其联合IL-2或IFNγ组IL-4含量显著高于对照组(P<0.05);而IL-10的含量,只有IFNγ组和rTgPGAM2+IFNγ组显著高于对照组(P<0.05)。结论 rTgPGAM2联合IL-2或IFNγ鼻内免疫小鼠诱导的脾淋巴细胞免疫应答优于rTgPGAM2单独免疫,表明IL-2和IFNγ具有良好的佐剂效应,IL-2的佐剂效应更佳。

Objective To observe the splenic lymphocyte immune response induced by intranasal immunization with recombinant Toxoplasma gondii phosphoglycerate mutase 2 （rTgPGAM2） in combination with interleukin-2 （IL-2） or interferon γ（IFNγ） in mice, and investigate the adjuvant effects of IL-2 and IFN% Methods Forty-eight BALB/c mice were randomly divided into six groups and immunized with 30 μg rTgPGAM2, 500 IU IL-2, 1 000 IU IFNγ, 30 μg rT- gPGAM2 ＋ 500 IU IL-2, 30 μg rTgPGAM2 ＋ 1 000 IU IFNγ and 20 μl PBS （control） respectively for 3 times by intranasal drip. The interval between the first and the second doses was 2 weeks, while that between the second and the third doses was one week. The mice were killed on day 14 after the third immunization, of which the proliferation activity of splenic lymphocytes were determined by CCK-8 method, and the IL-2, IFNγ, IL-4 and IL-10 levels in culture supernatant of splenic lymphocytes by ELISA. Results After stimulation with rTgPGAM2, the stimulation indexes （Sis） of splenic lymphocytes of mice were significantly higher in five test groups than in control group （P 〈 0. 05 or P 〈 0. 01 ）, and in rTgPGAM2 ＋ IL-2 and rTgPGAM2 ＋ IFN？ groups than in rTgPGAM2 group （P 〈 0. 01 or P 〈 0. 05）. However,after stimulation with ConA, only the SI in IL-2 group was higher than that in control group （P 〈 0. 01 ）. The IL-2 and IFN-/levels in culture supernatant of splenic lymphocytes were significantly higher in test groups than in control group（P 〈 0. 05）, and in rTgPGAM2 ＋ IL-2 and rTgPGAM2 ＋ IFNγ, groups than in rTgPGAM2 group（P 〈 0. 01 or P 〈 0. 05）. The IL-4 levels in rTgPGAM2, rTgPGAM2 ＋ IL-2 and rTgPGAM2 ＋ IFN＂/groups were significantly higher than that in control group （P 〈 0. 05）. However, only the IL-10 levels in IFNγ and rTgPGAM2 ＋ IFNγ groups were significantly higher than that in control group （P 〈 0. 05）. Conclusion The splenic lymphocyte immune response induced in mice by intranasal immunization with rTgPGAM2 in combination with IL-2 or IFNγ was superior to that by rTgPGAM2, indicating good adjuvant effect of IL-2 and IFNγ, especially IL-2.