猪圆环病毒2型灭活疫苗种毒株的筛选

为筛选满足猪圆环病毒2型灭活疫苗制苗要求的毒株,选择河南省8个地区的8株猪圆环病毒2型分离株进行抗原性分析,将各分离株培养后用不同滴度的病毒原液和其分别稀释至同一滴度(4.233×10⁴拷贝/μL)的病毒液分别制成油佐剂灭活疫苗,免疫小鼠后采血测定其抗体动态水平,以进行免疫效力评价。结果显示,8株圆环病毒2型分离株中8#和12#分离株原液制备的疫苗免疫后诱导产生的抗体水平较高,二免后1周抗体水平即高于1∶800,达到猪圆环病毒2型灭活疫苗的国家质量标准要求,3周时达到高峰,比对照商品疫苗诱导产生的抗体水平更高;其分别稀释130倍和463倍后制备的疫苗诱导产生的抗体水平在二免后3周也能达到1∶800。提示,猪圆环病毒2型8#和12#分离株毒价高,免疫效力良好,是理想的疫苗候选株。本研究丰富了猪圆环病毒2型灭活疫苗毒株的种毒资源,为研制高质量的猪圆环病毒2型疫苗奠定了基础。

Screening of Porcine Circovirus Type 2 Inactivated Vaccine Candidate Strain

To select porcine circovirus type 2 strain to meet the requirements for producing porcine circovirus type 2 inactivated vaccine, the efficacy and immunogenicity of 8 porcine circovirus type 2 strains from 8 regions of Henan province were assessed by measurement the antibody level of mice immunized with inactivated oil adjuvant vaccine which was manufactured with virus stock solution and diluted solution of same titer (4.233×10⁴ copies/μL). The antibody levels were induced by vaccines manufactured with 8# and 12# strains stock solution were higher and lasted longer than other strains and reference vaccines. The antibody titers at 1 week after the secondary immunization were above required minimum protective level of 1∶800 according to national quality standards of porcine circovirus type 2 inactivated vaccine. These results indicated that porcine circovirus type 2 of 8# and 12# strains could propagate well and had good immunogenicity and therefore could be chosen as candidate vaccine strains. This study enriched the resources of porcine circovirus vaccine strains and provided basis for developing high-quality porcine circovirus vaccine.