title: Immune responses in piglets infected with highly pathogenic porcine reproductive and respiratory syndrome virus.
abstract: Porcine reproductive and respiratory syndrome virus (PRRSV) infection compromises the host's innate and adaptive immunity. The aim of this study was to investigate the immune responses of piglets infected with highly pathogenic (HP) PRRSV (HuN4 strain) with or without the immunization with CH-1R attenuated PRRSV vaccine. The response was evaluated for the clinical signs, pathological changes and virus load in immune organs, antibody responses and levels of serum IFN-γ, IL-4 and IL-10. The result showed that in comparison with the piglets received the immunization, the piglets infected with HP-PRRSV alone had the thymus atrophy, decreased serum levels of IL-4 and increased serum levels of IL-10 and INF-γ. These results suggest that elevated IL-10 levels at the early stage of the infection may enhance virus survival and delay the induction of protective immunity, while increased levels of IL-4 induce the effective immune responses and increase the animals' health status.
authors: Department of Preventive Veterinary Medicine, College of Veterinary Medicine, Shandong Agricultural University, Taian, Shandong Province 271018, PR China.
authors: Gang
authors: G
authors: Wang
authors: Tengfei
authors: T
authors: Song
authors: Ying
authors: Y
authors: Yu
authors: Yonggang
authors: Y
authors: Liu
authors: Wenda
authors: W
authors: Shi
authors: Shujie
authors: S
authors: Wang
authors: Fulong
authors: F
authors: Rong
authors: Jianguo
authors: J
authors: Dong
authors: He
authors: H
authors: Liu
authors: Xuehui
authors: X
authors: Cai
authors: En-Min
authors: EM
authors: Zhou