Immune Effect Of Porcine Parvovirus N-2-HACC Inactivated Vaccine And VP2 Subunit Vaccine

Porcine parvovirus infection(Porcine parvovirus infection)is caused by porcine parvovirus(Porcine parvovirus,PPV).It is a reproductive disturbance disease of livestock,and its main clinical symptoms are stillbirth,fetal abnormality,mummification and abortion,also mixed infection with other diseases.PPV caused severe economic losses to the industry livestock.There is no effective treatment way of PPV.However,vaccination is an effective way to control PPV.A major problem with the use of attenuated vaccines is that they generally have low safety,the need of cold storage,and was used seldom.However,the inactivated vaccine is used commonly on the market to control PPV.In addition,genetic engineering subunit vaccine is becoming a newly-developing vaccine as it has higher security and good immunogenicity.Immunologic adjuvant is one part of vaccines which could improve the immune effect of antigen.Biological polysaccharide that has no toxicity is a good choice used in immune.Chitosan,one of the world's most abundant polysaccharide,has biocompatibility,biodegradability and made outstanding achievements in the field of adjuvants.We have prepared PPV-N-2-HACC and PPV/VP2-N-2-HACC with N-2-hydroxypropyltimehyl ammonium chloride chitosan(N-2-HACC)for adjuvants and porcine parvovirus and its VP2 protein liquid for antigens.1)The consistency of N-2-HACC in different batches is good,safe and stable;2)Addition dose of immune tests told that the best immunization effect is gest when adjuvant dose is 0.5%(volume/ volume);3)The finished product inspection of PPV-N-2-HACC and PPV/VP2-N-2-HACC was qualified;4)The safety of PPV-N-2-HACC and PPV/VP2-N-2-HACC was also tested in vivo by safety test in swinery;5)Storage stability tests showed that no significant changes in the appearance of PPV-N-2-HACC and PPV/VP2-N-2-HACC storage at 37?,20?,4? for 4 weeks,and have good stability;6)In vivo immunization showed that swinery immunized with the PPV-N-2-HACC and PPV/VP2-N-2-HACC induced more long-lasting HI antibodies and better immune responses;7)Swinery immunized with the PPV-N-2-HACC and PPV/VP2-N-2-HACC did not induced IL-2,IL-4 and IFN-? secretion and stimulate CD4+,CD8+ production,showed that the PPV-N-2-HACC and PPV/VP2-N-2-HACC protect swinery mainly through humoral immunity rather than cellular immunity;8)The protective efficacy of PPV-N-2-HACC and PPV/VP2-N-2-HACC was superior after challenge test;9)The real-time PCR assays based on TaqMan for detection PPV NS1 was established in this study,and the assays with high sensitivity,specificity which reproducibility could be used to detect PPV.The inactivated vaccine and genetic engineering subunit vaccine with adjuvant of N-2-HACC for porcine parvovirus had been prepared,which could induce higher HI antibody titer,increase the humoral immunity,and extended immune protection.In addition,this study lays a foundation for the further development of the vaccine adjuvant of N-2-HACC.