Laboratory of Virology, Department of Virology, Parasitology and Immunology, Faculty of Veterinary Medicine, Ghent University, B-9820 Merelbeke, Belgium.
Vet Microbiol. 2013 Dec 27;167(3-4):235-41. doi: 10.1016/j.vetmic.2013.07.020. Epub 2013 Aug 7.
Currently, little is known on the cellular pathogenesis of equine arteritis virus (EAV). The purpose of the present study was to identify the target cells in ponies experimentally inoculated with EAV 08P178 (EU, clade-1). EAV-target organs (respiratory tissues with associated lymphoid tissues and large intestines), collected at 3 and 7 days post inoculation (dpi) and with virus titers≥10(5.0) TCID50/g, were processed with double immunofluorescence staining for the simultaneous detection of EAV N-protein and one of the following cell markers: CD172a (myeloid cells), CD3 (T lymphocytes), IgM (B lymphocytes) and von Willebrand factor (endothelial cells). In the different analyzed organs, 31-58% and 47-63% of the EAV-positive cells were mononuclear leukocytes (mainly CD172a(+) followed by CD3(+)) at 3 and 7 dpi, respectively. EAV-positive endothelial cells were not detected in 3.200 large blood vessels (≥3 endothelial cells/vessel cross section). However, in terminal capillaries (1-2 endothelial cells/vessel cross section) of the different organs, 15-51% of the endothelial cells were EAV-positive. In conclusion, the present study demonstrates that EAV 08P178 (i) has a main tropism for CD172a(+) and CD3(+) mononuclear leukocytes and (ii) infects a large number of endothelial cells in terminal capillaries. EAV 08P178 infection in capillaries is most probably the cause of an increased vascular permeability leading to leakage of fluid (edema-serous exudate) but not to severe vasculitis and hemorrhages.
目前，人们对马动脉炎病毒（EAV）的细胞发病机制知之甚少。本研究旨在鉴定用 EAV 08P178（EU，clade-1）接种的小马的靶细胞。在接种后 3 天和 7 天（dpi），从 EAV 靶器官（具有相关淋巴组织的呼吸组织和大肠）中收集的病毒滴度≥10(5.0)TCID50/g 的组织，用双重免疫荧光染色进行处理，同时检测 EAV N 蛋白和以下一种细胞标志物：CD172a（髓细胞）、CD3（T 淋巴细胞）、IgM（B 淋巴细胞）和血管性血友病因子（内皮细胞）。在不同分析的器官中，31-58%和 47-63%的 EAV 阳性细胞在 3 和 7 dpi 时分别为单核白细胞（主要是 CD172a(+)，其次是 CD3(+)）。在 3.200 条大血管（每条血管横截面上≥3 个内皮细胞）中未检测到 EAV 阳性内皮细胞。然而，在不同器官的终末毛细血管（每条血管横截面上 1-2 个内皮细胞）中，15-51%的内皮细胞呈 EAV 阳性。总之，本研究表明，EAV 08P178（i）主要趋向于 CD172a(+)和 CD3(+)单核白细胞，（ii）感染大量终末毛细血管中的内皮细胞。EAV 08P178 在毛细血管中的感染很可能是导致血管通透性增加的原因，导致液体渗漏（水肿-浆液性渗出），但不会导致严重的血管炎和出血。
