title: Characterization of thymus atrophy in piglets infected with highly pathogenic porcine reproductive and respiratory syndrome virus.
abstract: Our previous study has demonstrated that piglets infected with highly pathogenic PRRSV (HP-PRRSV) induced significant thymus atrophy. The aim of this study was to further investigate the lesions in thymus of piglets infected with HP-PRRSV or PRRSV and the changes of thymic T cell populations. The lesions were evaluated for the thymus/body weight ratios, pathological changes and virus load in thymus, apoptosis and ultrastructure of thymocytes. The result showed that thymus/body weight ratios of HP-PRRSV-infected piglets were significantly reduced compared to PRRSV-infected or control piglets, and thymic lesions were characterized by severe cortical depletion of thymocytes. The number of thymocytes undergoing apoptosis was increased approximately forty-fold in piglets infected with HP-PRRSV than that of PRRSV on 7 days post-inoculation (DPI). Double-positive thymocytes of piglets infected with HP-PRRSV were suppressed to a greater degree than either single positive subpopulation, but similar results were not observed in piglets infected with PRRSV. These results suggested that HP-PRRSV induced abundant apoptosis might result in severe thymus atrophy and the depletion of thymocytes.
authors: State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China.
authors: Yuli
authors: Y
authors: He
authors: Gang
authors: G
authors: Wang
authors: Yonggang
authors: Y
authors: Liu
authors: Wenda
authors: W
authors: Shi
authors: Zifeng
authors: Z
authors: Han
authors: Jianan
authors: J
authors: Wu
authors: Chenggang
authors: C
authors: Jiang
authors: Shujie
authors: S
authors: Wang
authors: Shouping
authors: S
authors: Hu
authors: Huiqiang
authors: H
authors: Wen
authors: Jianguo
authors: J
authors: Dong
authors: He
authors: H
authors: Liu
authors: Xuehui
authors: X
authors: Cai
mesh_terms: D000818:Animals; D017209:Apoptosis; D001284:Atrophy / Q000473:pathology; D001835:Body Weight; D046529:Microscopy, Electron, Transmission; D019318:Porcine Reproductive and Respiratory Syndrome / Q000473:pathology*; D019316:Porcine respiratory and reproductive syndrome virus / Q000502:physiology*; D011897:Random Allocation; D013552:Swine; D013601:T-Lymphocytes / Q000473:pathology; D060168:Thymocytes / Q000473:pathology; D013950:Thymus Gland / Q000473:pathology* / Q000821:virology; D019562:Viral Load; D014766:Viremia / Q000662:veterinary