Kommers G D, King D J, Seal B S, Carmichael K P, Brown C C
Department of Pathology, College of Veterinary Medicine, University of Georgia, Athens 30602-7388, USA.
Vet Pathol. 2002 May;39(3):353-62. doi: 10.1354/vp.39-3-353.
The pathogenesis of six pigeon-origin isolates of Newcastle disease virus (NDV) was investigated in chickens. Four isolates were previously defined as the variant pigeon paramyxovirus 1 (PPMV-1), and two isolates were classified as avian paramyxovirus 1 (APMV-1). Birds inoculated with PPMV-1 isolates were euthanatized, and tissue samples were collected at 2, 5, and 10 days postinoculation (DPI). Birds inoculated with APMV-1 isolates died or were euthanatized, and tissue samples were collected at 2, 4, and 5 DPI. Tissues were examined by histopathology, immunohistochemistry (IHC) for the presence of NDV nucleoprotein, and in situ hybridization (ISH) for the presence of viral mRNA for the matrix gene. Spleen sections were stained by the terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) assay and by IHC using an anti-active caspase-3 antibody (IHC-Casp) to detect apoptotic cells. Brain sections of PPMV-1-infected birds were examined by IHC to detect T and B lymphocytes and glial fibrillary acidic protein (GFAP). Histologically, birds inoculated with PPMV-1 isolates had marked lesions in the heart and brain. Presence of viral nucleoprotein and viral mRNA in the affected tissues was confirmed by IHC and ISH, respectively. Numerous reactive astrocytes were observed in brain sections stained for GFAP Among all the isolates, the IHC-Casp demonstrated that apoptosis was very prominent in the ellipsoid-associated cells of the spleen at 2 DPI. Results of the TUNEL assay indicated that apoptotic cells were prominent at 5 DPI and were more randomly distributed. The clinical signs and gross and histopathologic changes observed in the APMV-1-infected birds were characteristic of an extensive infection with highly virulent NDV evident by IHC.
对6株鸽源新城疫病毒（NDV）分离株在鸡体内的致病机制进行了研究。4株分离株先前被定义为变异型鸽副黏病毒1型（PPMV-1），2株分离株被归类为禽副黏病毒1型（APMV-1）。接种PPMV-1分离株的鸡在接种后2、5和10天进行安乐死，并采集组织样本。接种APMV-1分离株的鸡死亡或被安乐死，并在接种后2、4和5天采集组织样本。通过组织病理学、免疫组织化学（IHC）检测NDV核蛋白的存在以及原位杂交（ISH）检测基质基因的病毒mRNA对组织进行检查。脾脏切片通过末端脱氧核苷酸转移酶介导的dUTP缺口末端标记（TUNEL）试验以及使用抗活性半胱天冬酶-3抗体的免疫组织化学（IHC-Casp）进行染色，以检测凋亡细胞。对PPMV-1感染鸡的脑切片进行免疫组织化学检查，以检测T和B淋巴细胞以及胶质纤维酸性蛋白（GFAP）。组织学上，接种PPMV-1分离株的鸡在心脏和脑部有明显病变。分别通过免疫组织化学和原位杂交证实了受影响组织中病毒核蛋白和病毒mRNA的存在。在GFAP染色的脑切片中观察到大量反应性星形胶质细胞。在所有分离株中，免疫组织化学-半胱天冬酶显示，在接种后2天，脾脏椭圆体相关细胞中的凋亡非常明显。TUNEL试验结果表明，凋亡细胞在接种后5天很明显，且分布更随机。免疫组织化学显示，APMV-1感染鸡的临床症状以及大体和组织病理学变化是高致病性NDV广泛感染的特征。
