Heggen C L, Qureshi M A, Edens F W, Barnes H J, Havenstein G B
Department of Poultry Science, College of Veterinary Medicine, North Carolina State University, Raleigh 27695-7608, USA.
Avian Dis. 1998 Oct-Dec;42(4):711-20.
In vivo and in vitro mononuclear phagocytic system functions, expression of lymphocyte subset cell surface markers in the thymus and bursa of Fabricius, and lymphocyte subset dynamics during the course of poult enteritis and mortality syndrome (PEMS) were examined. PEMS is an acute, transmissible, infectious intestinal disease accompanied by high mortality and morbidity. The etiology of this multifactorial disease remains to be elucidated; however, turkey coronavirus was initially assumed to be one of the primary agents involved. Further investigation demonstrated that turkey coronavirus was not always detectable in poults exhibiting PEMS symptoms, and, thus, PEMS poults began to be identified as positive or negative for turkey coronavirus. In each trial, uninfected hatchmate controls were compared with turkey poults that were contact exposed to PEMS poults at 7 days of age. Following intravenous inoculation, control poults cleared Escherichia coli from their circulation by 60 min, whereas viable E. coli were still present in the circulation of PEMS poults at 60 min postinoculation. Inflammatory response measured by Sephadex-elicited abdominal exudate cell recruitment and the adherence potential of abdominal exudate cells was not significantly different between uninfected and PEMS poults. The percentage of glass-adherent abdominal exudate macrophages was higher in PEMS poults. However, the ability of these macrophages to phagocytize sheep red blood cells and the average number of sheep red blood cells per phagocytic macrophage were both lower compared with uninfected controls. CD4+ expression in thymic tissue of PEMS poults at 9 days postinfection was significantly lower. The CD4+:CD8+ lymphocyte ratio in peripheral blood leukocytes from coronavirus-negative PEMS poults was lower than that from both uninfected and coronavirus-positive PEMS poults at 14 days postinfection. In the spleen, the CD4+:CD8+ lymphocyte ratio was higher in coronavirus-positive PEMS poults as compared with the other treatments. In conclusion, immune system dysfunction in PEMS is associated with impaired mononuclear phagocytic system function and alterations in lymphocyte populations.
研究了体内和体外单核吞噬系统的功能、胸腺和法氏囊中淋巴细胞亚群细胞表面标志物的表达，以及雏鸡肠炎和死亡综合征（PEMS）病程中淋巴细胞亚群的动态变化。PEMS是一种急性、可传播的感染性肠道疾病，伴有高死亡率和发病率。这种多因素疾病的病因仍有待阐明；然而，火鸡冠状病毒最初被认为是主要致病因子之一。进一步研究表明，在出现PEMS症状的雏鸡中并非总能检测到火鸡冠状病毒，因此，PEMS雏鸡开始被鉴定为火鸡冠状病毒阳性或阴性。在每项试验中，将未感染的同窝对照与7日龄时接触PEMS雏鸡的火鸡雏鸡进行比较。静脉接种后，对照雏鸡在60分钟内清除了循环中的大肠杆菌，而接种后60分钟，PEMS雏鸡的循环中仍存在活的大肠杆菌。未感染和PEMS雏鸡之间，通过葡聚糖诱导的腹部渗出细胞募集和腹部渗出细胞的黏附潜能来衡量的炎症反应没有显著差异。PEMS雏鸡中玻璃黏附的腹部渗出巨噬细胞百分比更高。然而，与未感染对照相比，这些巨噬细胞吞噬绵羊红细胞的能力以及每个吞噬性巨噬细胞吞噬的绵羊红细胞平均数量均较低。感染后9天，PEMS雏鸡胸腺组织中的CD4 +表达显著降低。感染后14天，冠状病毒阴性的PEMS雏鸡外周血白细胞中的CD4 +:CD8 +淋巴细胞比率低于未感染和冠状病毒阳性的PEMS雏鸡。在脾脏中，与其他处理相比，冠状病毒阳性的PEMS雏鸡的CD4 +:CD8 +淋巴细胞比率更高。总之，PEMS中的免疫系统功能障碍与单核吞噬系统功能受损和淋巴细胞群体改变有关。
