Iamohbhars Nuttipa, Cabic Alpha Grace B, Markbordee Boonkanit, Shiina Ryota, Tamura Natsumi, Shiwa-Sudo Nozomi, Kimitsuki Kazunori, Espino Mark Joseph M, Manalo Daria Llenaresas, Inoue Satoshi, Park Chun-Ho
Department of Veterinary Pathology, School of Veterinary Medicine, Kitasato University, 23-35-1, Higashi, Towada 034-8628, Aomori, Japan.
Research Institute for Tropical Medicine, Department of Health, 9002 Research Drive, Filinvest Corporate City, Alabang, Muntinlupa City 1781, Philippines.
Vet Sci. 2025 Mar 24;12(4):299. doi: 10.3390/vetsci12040299.
The trigeminal nerve is the primary gateway through which the rabies virus enters the brain. Viral infection-related trigeminal neuritis is associated with certain clinical signs. This study investigated trigeminal ganglion histopathology in 92 rabid dogs. Trigeminal ganglionitis was classified into three pathological grades: mild, moderate, and severe. Immunostaining of selected sections was performed using antibodies against lymphocytes (CD3, CD20), stellate cells (glial fibrillary acidic protein, GFAP), macrophages (Iba-1, HLA-DR), ganglion cells (neurofilament, NF), and Schwann cells (S-100) to identify lesion cell types. In moderate and severe cases, double-immunofluorescence staining was performed to determine neuronophagia and Nageotte nodule cell types. Mild (13.0%) cases had minimal morphological changes in ganglion cells; moderate (56.5%) and severe (30.4%) cases showed infected ganglion cells and axons with degenerative necrosis, which were replaced by inflammatory cells. Immunohistochemically, viral antigens were detected in most ganglion cells in mild cases and were significantly reduced in severe cases. The number of CD3-, CD20-, GFAP-, and Iba-1-positive cells increased as the severity progressed, and neuronophagia and Nageotte nodules primarily comprised HLA-DR-positive cells. These findings suggest that the rabies virus reaches the trigeminal ganglion via ascending or descending routes and induces trigeminal neuropathological changes, contributing to neurological symptoms in rabid dogs.
三叉神经是狂犬病病毒进入大脑的主要通道。病毒感染相关的三叉神经炎与某些临床症状有关。本研究调查了92只患狂犬病犬的三叉神经节组织病理学。三叉神经节炎分为轻度、中度和重度三个病理等级。使用针对淋巴细胞（CD3、CD20）、星状细胞（胶质纤维酸性蛋白，GFAP）、巨噬细胞（Iba-1、HLA-DR）、神经节细胞（神经丝，NF）和施万细胞（S-100）的抗体对选定切片进行免疫染色，以确定病变细胞类型。在中度和重度病例中，进行双重免疫荧光染色以确定噬神经细胞和纳热奥特小结的细胞类型。轻度（13.0%）病例的神经节细胞形态变化最小；中度（56.5%）和重度（30.4%）病例显示受感染的神经节细胞和轴突出现退行性坏死，并被炎症细胞取代。免疫组织化学检测显示，轻度病例中大多数神经节细胞可检测到病毒抗原，重度病例中病毒抗原显著减少。随着病情严重程度的增加，CD3、CD20、GFAP和Iba-1阳性细胞数量增加，噬神经细胞和纳热奥特小结主要由HLA-DR阳性细胞组成。这些发现表明，狂犬病病毒通过上行或下行途径到达三叉神经节，并引发三叉神经病理变化，导致患狂犬病犬出现神经症状。
