基于悬浮细胞制备的鸡新城疫-H9亚型禽流感二联灭活疫苗(La Sota株+BX13株)安全性和免疫产生期研究

Safety and Onset Time of Immunity Protection to Bivalent Inactivated Vaccine of Newcastle Disease-H9 Subtype Avian Influenza(La Sota Strain+BX13 Strain)Based on Suspension Cell Culture

为探讨悬浮细胞制备的鸡新城疫-H9亚型禽流感二联灭活疫苗(La Sota株+BX13株)(以下简称二联灭活疫苗)的安全性和免疫产生期,试验用新城疫病毒(NDV)La Sota株和H9亚型禽流感病毒(AIV)BX13株分别接种BHK-21和MDCK悬浮细胞,收获抗原液,制备二联灭活疫苗;采用1 mL/只的剂量接种21日龄SPF鸡进行二联灭活疫苗的安全性试验;以0.02、0.05、0.1、0.3、0.5 mL/只的剂量接种21日龄SPF鸡,免疫后7、14、21 d采血测定NDV HI和AIVHI抗体,并于免疫后21日龄攻毒进行免疫保护试验和免疫产生期试验。结果显示:二联灭活疫苗对SPF鸡安全,鸡只无不良反应,疫苗吸收良好;各剂量组免疫后抗体水平均逐渐升高,免疫后21 d NDV HI效价为6.1~8.5 log2,AIV HI效价为7.5~11.2 log2;免疫后21 d,0.02 mL/只剂量组对两种毒株的攻毒保护率均为9/10,其余剂量组均为10/10保护。研究表明,二联灭活疫苗对SPF鸡安全,以0.1 mL/只的剂量免疫SPF鸡21 d可获得对NDV和H9 AIV的有效抵抗。

In order to study the safety and onset time of immunity protection of bivalent inactivated vaccine of Newcastle disease and H9 subtype avian influenza(La Sota strain+BX13 strain)based on suspension cells culture,hereinafter referred to bivalent inactivated vaccine.Newcastle disease virus(NDV)La Sota strain and H9 subtype avian influenza virus(AIV)BX13 strain was used to inoculate BHK-21 and MDCK suspension cells,respectively,and the antigen solution was harvested,and with which the bivalent inactivated vaccine was prepared.The safety test of the vaccine was carried out by inoculating 21-day-age SPF chickens with the dose of 1 mL/chicken.The onset of immunity protection test was conducted by inoculating 21-days-age SPF chickens with the doses of 0.02,0.05,0.1,0.3,0.5 mL/chicken,respectively.Blood samples were collected at 7,14 and 21 days after immunization,NDV HI and H9 subtype AIV HI titers were detected.The challenge test was carried out at 21 days after immunization.The results showed that the vaccine was safe to SPF chickens,no clinical symptoms was found in chickens and no vaccine residual was found at injection site.The antibody level gradually increased with the increase of immune dose and immune time.The NDV HI titer was 6.1 to 8.5 log2and the AIV HI titer was 7.5 to 11.2 log221 days after immunization.At 21 days after immunization,the protection rate of 0.02 mL/chicken dose group against the two strains was 9/10,the other dose groups was 10/10.The results showed that bivalent inactivated vaccine was safe to SPF chickens and the effective protection could be obtained at 21 days after immunization with 0.1 mL/chickens to NDV and H9 AIV.