猪白细胞介素4,6融合基因和CpG基序对猪蓝耳病疫苗免疫的强化效应

为探索新型高效安全的猪蓝耳病疫苗免疫佐剂,本实验用离子交联法制备壳聚糖纳米颗粒包裹猪融合基因PIL-46和CpG基序的真核表达质粒(CNP-(VRIL-46 VR1C)),将CNP-(VRIL-46 VR1C)肌注接种过猪蓝耳病灭活苗的长白川白杂交猪,接种后1、2、4、6和8周采取实验猪静脉血,用Sandwich ELISA检测血清中白细胞介素2(IL-2)、IL-4、IL-6和IgG、IgA、IgM及特异抗体的含量,同时检测外周血液免疫细胞数量的变化。结果发现实验猪接种CNP-(VRIL-46 VR1C)后1～8周内,其血清中IL-2、IL-4、IL-6和IgG、IgA、IgM及特异抗体的含量较对照组均显著增多(P<0.05),淋巴细胞和单核细胞数量也明显升高(P<0.05)。这些表明接种CNP-(VRIL-46 VR1C)的实验猪的特异体液和细胞免疫水平均显著多于对照组,提示PIL-46基因和CpG基序组合能显著增强猪的特异体液和细胞免疫机能,明显提高其免疫防御力,具有研制为高效安全的分子免疫增强剂的应用前景。

Potentializtion of Immunity to PRRSV by Inoculation with Fusion Gene of Pig IL-4,IL-6 and CpG Motifs

In order to develop safe and effective immunoadjuvant for porcine reproductive and respiratory syndrome vaccine (PRRSV), the recombinant eukaryotic expression plasmid for the fusion gene of porcine IL-6 and IL-4 (PIL-46), and specific CpG Oligodeoxynucleotides (ODN) were packed with chitosan nanoparticles(CNP) prepared by ionic cross linkage, named as CNP-(VRIL-46 VR1C). Then the CNP-(VRIL-46 VR1C) was intramuscularly inoculated into Landrace and Chuanbai hybrid pig at the age of 14 days which were simultaneously immunized with inactivated porcine reproductive and respiratory syndrome vaccine. The peripheral blood of experimental pigs were collected at 1, 2, 4, 6 and 8 weeks post inoculation to detect the content of immunoglobulins, specific antibody and IL-2, IL-4 and IL-6 by the Sandwich ELISA. The results showed that from the 1 week to 8 weeks post vaccination, the levels of immunoglobulins, cytokines, the specific antibodies as well as the numbers of lymphocytes significantly increased in the blood of vaccinated pigs inoculated with CNP-(VRIL-46 VR1C) in comparison with those of control group. These findings suggest that CNP-(VRIL-46 VR1C) could significantly enhance the specific humoral and cellular immunity of porcine to PRRSV, indicating that the CNP-(VRIL-46 VR1C) could be utilized as a novel effective adjuvant to improve the immunity and resistance of animals against PRRSV.