传染性法氏囊病病毒超强毒感染SPF鸡免疫器官中CD4^+和CD8^+T淋巴细胞动态分布

Kinetic Distributions of Subsets CD4^+ and CD8^+ T Lymphocytes in Various Immune Organs of SPF Chicks with Inoculation of very Virulent Infectious Bursal Disease Virus

利用免疫组织化学染色对传染性法氏囊病病毒 (IBDV)超强毒 L X株感染 SPF鸡免疫器官中 CD4 + 和 CD8+ T淋巴细胞的动态分布进行了研究。超强毒 L X株接种 2周龄 SPF雏鸡 ,在其法氏囊、脾脏、胸腺、盲肠扁桃体、骨髓和哈氏腺中均可检出 IBDV抗原的存在和 CD4 + 与 CD8+ T淋巴细胞的数量改变。在法氏囊中 ,CD4 + T淋巴细胞主要存在于淋巴滤泡间隙和滤泡皮质 ,而 CD8+ T淋巴细胞则存在于整个淋巴滤泡和滤泡间隙 ,并且 CD8+ T淋巴细胞数量明显多于 CD4 + T淋巴细胞 ,在接种后 14 d仍未见 CD4 + 和 CD8+ T淋巴细胞数量减少。脾脏中 CD4 + T淋巴细胞主要存在于外周小动脉淋巴鞘或散在 ,而 CD8+ T淋巴细胞则多存在于外周小动脉淋巴鞘和红髓。接种后胸腺中 CD4 +和CD8+ T淋巴细胞在皮质中减少 ,但在髓质增多 ,尤其是 CD8+ T淋巴细胞数明显多于 CD4 + T淋巴细胞。盲肠扁桃体中 CD4 + 和 CD8+ T淋巴细胞主要存在于生发中心 ,尤其是 CD8+ T淋巴细胞数比 CD4 + T淋巴细胞明显多。骨髓和哈氏腺中也可见 CD4 +和 CD8+ T淋巴细胞 ,而且 CD8+ T淋细胞更多。在这些淋巴器官中 ,病毒损伤部位出现 CD4 +和 CD8+ T淋巴细胞的迁入聚集 ,表明 T淋巴细胞可能参与 IBDV超强毒的免疫致病过程。

Immunohistochemical staining was used to detect kinetic alterations of subsets CD4 + and CD8 + T lymphocytes and distribution of infectious bursal disease virus(IBDV) with very virulent IBDV(vvIBDV) strain LX.The IBD viral antigens were observed in cytoplasm located in bursae,spleen,thymus,cecal tonsils,bone marrow,and Harderian gland,and numerous CD4 + and CD8 + T lymphocytes observed in lesion areas located in these lymphoid tissues postinoculation(PI).In bursae,the number of CD4 + T cells was always lower than the number of CD8 + T cells,and CD4 + cells were mostly found in clusters in the interfollicular tissue and cortex,whereas CD8 + cells were more scattered and mostly infiltrated the cortex and medullae or their remnants.And obvious decreases in the number of CD4 + and CD8 + T cells were not still observed on the fourteenth day PI.In spleen,CD4 + T cells were mainly found in the periarteriolar lymphoid sheaths or scattered,whereas CD8 + T cells tended to cluster in the periarteriolar lymphoid sheaths and red pulp.In thymus,decreases in the number of CD4 + and CD8 + T cells in the cortex were evident,whereas these cells increased in the medulla,and CD8 + cells were more prevalent than CD4 + cells.CD4 + and CD8 + T cells were present in the germinal centers of cecal tonsils PI,but the number of CD8 + cells was obviously higher than the number of CD4 + cells.CD4 + and CD8 + T cells were also detected in the bone marrow and Harderian gland PI.This results showed that CD4 + and CD8 + T lymphocytes flowed into and located in lesion areas of various immune organs after inoculation of vvIBDV strain LX, indicating that T lymphocytes may play a role in the immunopathology of very virulent infectious bursal disease virus infection.