الفهرس 
AbstractOnly 14 pages are availabe for public view
 |  | from | 267 |  |  |
| | | from | 267 | | |
Abstract
In the present study cytokines m RNA gene expression were quantified in response to infection with HPAI classical and variant strain in vitro and in vivo and in response to vaccination with whole inactivated classical and variant strain based vaccine. Invitro study using HD11 reveal high IL6 and IL4 in response to high dose infection correlated with death of cells with in 24hrs with both strain while, with lower dose variant strain showed higher cytokines response except IFNγ correlated with lower virus titer than classical strain the same recorded at PBMC model of infection but higher IFNγ response recorded with variant strain correlated with almost the same viral titer for both strain at different time point. In vivo study revealed higher ability of variant strain based vaccine to induce early higher cytokines response that ensured by invitro study of the effect of both strain antigen on HD11 cell line that give result parallel to that concluded by in vivo study , while latter classical strain based vaccine induced higher cytokines response (acquired immunity) specially Th2 cytokines that ensured by higher HI titer comparing to variant strain based vaccine. Challenge study reveal higher viral titer and early death occurrence in case of classical strain challenge that correlated with higher expression of IL6 and more down regulation of IFNα and lower expression of IL10 and IFNγ in lung comparing to variant strain challenge that showed lower virus titer and delay of death time and presence of clinical symptoms that correlated with normal IFNα expression, lower proinflammatory cytokines and higher IL10 and IFNγ expression while result of cytokines expression in spleen revealed higher immune response with variant strain. Homologous challenged vaccinated chicken reveal higher IL4, IFNα and lower proinflammatory cytokines ,IL10 and IFNγ that correlated with higher HI titer , lower virus titer and absence of clinical symptoms comparing to heterologous challenge .