纳米乳作为流感疫苗佐剂的免疫效果及安全性的初步研究

Preliminary Research on Immune Effect and Safety of Nanoemulsion as Adjuvant for H3N2 Inactivated Influenza Vaccine

目的研究一种纳米乳作为H3N2灭活流感疫苗佐剂的佐剂效果,并对其安全性进行评价。方法取标准体重的清洁级ICR雌性小鼠随机分组,以纳米乳作为疫苗佐剂配制H3N2流感疫苗免疫小鼠,并以相应剂量的氢氧化铝佐剂组、无佐剂疫苗组和生理盐水组作为对照。在初免后的21天,进行加强免疫1次,自初免之日起,每隔7天,尾动脉采血,分离血清,测定血凝抑制(HI)抗体效价。初免后6天内,每隔2天称量小鼠,监测小鼠体重变化,并通过最大给药量实验测定纳米乳佐剂的急性毒性,以对纳米乳佐剂的安全性进行评价。结果纳米乳佐剂疫苗组小鼠血清HI抗体效价在加强免疫后快速升高,在第6周达到最高峰,效价远大于氢氧化铝佐剂组和无佐剂疫苗组,之后,纳米乳佐剂组HI抗体效价维持在较高水平。纳米乳佐剂组小鼠体重增长正常,与其他组之间无显著性差异。通过腹腔注射,测得小鼠对纳米乳佐剂的最大耐受量>25g/kg,本纳米乳佐剂属无毒级物质。结论此纳米乳作为佐剂可以有效提升流感疫苗抗原的免疫原性,增强免疫效果,且显示出了较好的安全性,是一种良好的流感疫苗佐剂候选。

Objective To study the adjuvant effect of a kind of nanoemulsion as the H3N2 inactivated influenza vaccine adjuvant and make an assessment of its security. Methods The standard weight ICR mice were grouped averagely and randomly. The H3N2 inactivated influenza vaccine Prepared with nanoemulsion as adjuvant and immunized the mice. And mice were also immunized with corresponding dose of aluminium - adjuvanted inactivated vaccine, inactivated vaccine alone and physiological saline as control groups. All the mice were immunized again 21 days after the primary immunization. The blood samples were collected every 7 days after the primary immunization for the measure- ment of HI antibody titers. During the 6 days after the primary immunization,the body weight of mice was weighed every 2 days. And the acute toxicity of the nanoemulsion was measured through the maximum dose experiment to assess its security. Results The HI antibody titers of nanoemulsion - adjuvanted inactivated vaccine group growed quickly after the second immunization, and reached a peak in the sixth week. It was much higher than that of the aluminium - adjuvanted inactivated vaccine group and inactivated vaccine alone group. After six weeks, it still remained at a high level. The body weight of the nanoemulsion - adjuvanted vaccine group growed normally. It showed no significant difference with other groups. The MTD（maximal tolerance dose） of the nanoemusion in mice was more than 25g/kg by intraperitoneal injec- tion. It was nontoxic substance. Conclusion The nanoemulsion can effectively enhance the immunogenicity of influenza antigen and the im- mune effect of influenza vaccine. It also shows good security. So,it is a good candidate adjuvant for influenza vaccine.