猪白细胞介素4、6融合基因对小鼠免疫的影响

Effect of Fusion Gene of Porcine Interleukin 6 and 4 on the Immunity of Mice

目的:研究猪白细胞介素IL4、IL6融合基因(PIL46)对小鼠免疫应答的反应。方法:以壳聚糖纳米颗粒包裹融合基因(PIL46)的真核表达质粒(VPIL46)接种昆明小鼠,免疫后28日以口服攻毒实验小鼠,观察其体液和细胞免疫水平指标的变化和病变情况。实验结果发现:CNP包裹VPIL46接种小鼠体液免疫和细胞免疫指标不同程度地增多,均显著高于对照组(P<0.05);与CNP包裹VPIL4+6免疫效果相近。免疫后28日以口服攻毒实验小鼠,检测结果发现:CNP包裹VPIL46组和CNP包裹VPIL4+6组小鼠的上述免疫指标除中性粒细胞外均显著多于对照小鼠,免疫小鼠无症状和病变,健康存活;而对照小鼠均发病,消化道组织器官呈现明显出血病变。结论:PIL46基因具有显著增强小鼠体液和细胞免疫机能、提高对大肠杆菌感染抵抗力的免疫调节效应,可作为有效的抗感染免疫调节剂。

Objective To research the immunopotentiation of a novel fusion gene of porcine interleukin-6 and -4 on immunity of mice. Methods The eukaryotic expression plasmid of fusion gene of porcine interleukin-6 and -4 was entrapped with chitosan-nanoparticle （CNP） prepared by the method of ionic cross linkage to immunize Kunming mice at the age of 21 days, and then the experimental mice were orally challenged with virulent E. coli bacteria 28 days post-inoculation. The peripheral blood were weekly collected from the tail vein of inoculated mice to detect the content of IgG, lgA, IgM and specific antibody against E. coli as well as the levels of interleukin 2 （IL2）, IL4 and IL6 by the SABC-ELISA. The number of lymphocytes, monocytes, granulocytes and white blood cells were aiso counted out as the routine method. Resuits The humoral land cellular immnne values were respectively elevated to different extent in the mice vaccinated with VPIL46 or VPIL4 ＋ 6. The immunized mice all survived without symptoms and lesions after challenge, while the control mice appeared evident symptoms and hemorrhagic lesions mainly in digestive tissues and organs. Conclusion The PIL46 fusion gene could significantly promote the humoral and cellular immunity and resistance of mouse against E. coli infec tion, and would be utilized as an effective adjuvant to improve the immunity and resistance of animals against infectious diseases.