Yan Yuyan, Zhao Zuotao, Wan Hongfei, Wu Ruochen, Fang Jugao, Liu Honggang
Department of Pathology, Affiliated Beijing Tongren Hospital, Capital Medical University, Beijing, 100730, People's Republic of China.
Department of Dermatology, First Hospital, Peking University, Beijing, 100034, People's Republic of China.
BMC Infect Dis. 2014 Dec 20;14:3856. doi: 10.1186/s12879-014-0713-y.
Acute invasive fungal rhinosinusitis is a lethal infectious process afflicting immunocompromised individuals. Knowledge about this disease is still limited due to the scarcity of animal models designed to study the pathogenesis of this infection. Mast cells are tissue-resident immune cells that participate in a variety of allergic and inflammatory conditions. Limited attention has been given to the role of mast cells in acute invasive fungal rhinosinusitis. Therefore, the objectives of this study were to create a rat model of acute invasive fungal rhinosinusitis based on analyzing the impact of different fungal concentrations on establishing infection, and to observe the changes of mast cells in rats with this disease.
Sprague-Dawley rats were divided randomly into four groups, three of which were experimental and received different concentrations of Aspergillus fumigatus inoculations, and one was a control group (D). The inoculated Aspergillus fumigatus concentrations were 5 × 10(7) conidia/ml in group A, 10(7) conidia/ml in group B, and 10(6) conidia/ml in group C. Before fungal inoculation, rats were immunosuppressed using cyclophosphamide and cortisone acetate, and had Merocel sponges inserted into the right nares. Hematology and histopathology investigations were then performed.
An acute invasive fungal rhinosinusitis rat model was established successfully with an incidence rate of 90% in group A, 50% in group B and 10% in group C. Aspergillus fumigatus invasion was observed in 20% of the lungs in group A, but was not seen in the remaining groups. In addition, no fungi invaded the orbital tissue, brains, livers, spleens or kidneys of any rat. Compared with the control set, the total number of mast cells in the experimental groups was not significantly increased, but mast cell degranulation, on the other hand, was only found in infected nasal cavities.
This investigation illustrates that various fungal concentrations have different effects on the incidence of acute invasive fungal rhinosinusitis, and it also demonstrates the feasibility of using this model to study the process of fungal rhinosinusoidal invasion. In addition, the results suggest that mast cells may play a role in the protection of sinuses against acute Aspergillus fumigatus infection and in the clearance of established hyphal masses.
急性侵袭性真菌性鼻窦炎是一种致命的感染性疾病，主要影响免疫功能低下的个体。由于缺乏用于研究这种感染发病机制的动物模型，关于该疾病的知识仍然有限。肥大细胞是驻留在组织中的免疫细胞，参与多种过敏和炎症反应。肥大细胞在急性侵袭性真菌性鼻窦炎中的作用尚未得到足够关注。因此，本研究的目的是通过分析不同真菌浓度对感染建立的影响，建立急性侵袭性真菌性鼻窦炎大鼠模型，并观察患有该疾病大鼠体内肥大细胞的变化。
将Sprague-Dawley大鼠随机分为四组，其中三组为实验组，分别接种不同浓度的烟曲霉菌，一组为对照组（D组）。A组接种的烟曲霉菌浓度为5×10⁷ 个孢子/ml，B组为10⁷ 个孢子/ml，C组为10⁶ 个孢子/ml。在接种真菌前，使用环磷酰胺和醋酸可的松对大鼠进行免疫抑制，并将Merocel海绵插入右侧鼻孔。然后进行血液学和组织病理学检查。
成功建立了急性侵袭性真菌性鼻窦炎大鼠模型，A组发病率为90%，B组为50%，C组为10%。在A组中，观察到20%的大鼠肺部有烟曲霉菌侵袭，其余组未观察到。此外，没有真菌侵袭任何大鼠的眼眶组织、大脑、肝脏、脾脏或肾脏。与对照组相比，实验组肥大细胞总数没有显著增加，但肥大细胞脱颗粒仅在感染的鼻腔中发现。
本研究表明，不同真菌浓度对急性侵袭性真菌性鼻窦炎的发病率有不同影响，同时也证明了使用该模型研究真菌性鼻窦炎侵袭过程的可行性。此外，结果表明肥大细胞可能在保护鼻窦免受急性烟曲霉菌感染以及清除已形成的菌丝团块中发挥作用。
