鸡感染J亚群禽白血病病毒的免疫抑制机理

通过人工接种建立了雏鸡感染J亚群禽白血病病毒（ALV-J）后发生免疫抑制的病理模型。对免疫抑制的机理进行了初步研究。结果表明：ALV-J感染早期可诱导胸腺、法氏囊的淋巴细胞凋亡，这种早期的淋巴细胞凋亡是胸腺和法氏囊萎缩的重要原因之一。病理组织学动态观察表明。ALV-J主要引起骨髓的髓系细胞灶状或弥漫性增生，病变导致骨髓机能受损，使机体免疫机能下降。是引起免疫抑制的根本原因。病毒感染组免疫器官均发生了严重的实质萎缩性病变．这种病变的发生除与骨髓的病变及淋巴细胞凋亡有关外。还与中后期淋巴细胞的坏死有关．从而导致严重的免疫抑制。ALV-J感染可引起免疫器官及部分内脏器官中嗜酸性粒细胞样的瘤细胞浸润增生，这可以作为病毒感染早期的病理诊断指标。

Immunosuppressive Mechanism of Broilers Infected with Avian Leukosis Virus Subgroup J (ALV-J)

Pathological model was successfully established in commercial broilers at one-day-old by inoculating avian leukosis virus subgroup J(ALV-J) strain NX0101 for primary study of the immunosuppressive mechanism caused by ALV-J.Apoptosis of lymphocytes in bone marrow,spleen,thymus and bursa was detected by electron microscope and TUNEL staining.The results showed ALV-J could induce apoptosis of lymphocytes in thymus,bursa and spleen,which was mainly found in early time(in two weeks).So it was concluded that the apoptosis of lymphocytes was one of the reasons that lead to atrophy of immune organs and immunosuppression of body.Dynamic changes of histopathology were studied on immune organs and some visceral organs such as liver,kidney,cardiac muscle and lung.The results showed that ALV-J mainly conduced hyperplasia of eosinocytes in bone marrow.Therefore,lesions of bone marrow was the essential reason causing immunosuppression.The material atrophy in other immune organs,which was related to lesions of bone marrow and apoptosis or necrosis of lymphocytes was the direct reason for immunosuppression.