小鼠变应性鼻炎合并急性细菌性鼻窦炎的初步研究

目的 探讨变应性鼻炎动物模型合并急性细菌性鼻窦炎的方法.方法 清洁级C57BL6/J小鼠40只,随机分为4组:A组(卵清蛋白+肺炎链球菌);B组(卵清蛋白+生理盐水);C组磷酸盐缓冲溶液(phosphate buffered solution,PBS)+肺炎链球菌];D组(PBS+生理盐水),每组各10只.①实验第1～9天,A组和B组每天腹腔注射200μl 10%卵清蛋白,第10～17天A、B组用6%卵清蛋白鼻腔局部激发建立变应性鼻炎模型,C组和D组用等量PBS替代,步骤同前;②于实验第13天A组和C组鼻腔接种肺炎链球菌ATCC 49619 200μl;B组和D组用等量生理盐水代替.接种后第6天处死动物,处死前各组动物行内眦静脉采血,以间接酶联免疫吸附试验检测血清白介素5水平.取鼻面骨,石蜡包埋,连续切片,行HE染色和0.5%甲苯胺蓝染色,计算机辅助显微镜下观察肥大细胞脱颗粒情况,并计算每平方毫米鼻窦黏膜中多形核中性粒细胞和嗜酸粒细胞的数量.结果 A组和B组分别有9只和8只动物变应性鼻炎建模成功,鼻部症状、黏膜水肿和黏膜下微血管明显扩张,C组症状轻微,D组无任何症状.A组鼻窦黏膜多形核中性粒细胞密度(-x±s)为(139.3±26.5)个/mm2,高于B组(70.7±16.7)个/mm2、C组(63.0±14.7)个/mm2和D组(40.2±14.1)个/mm2(P值均＜0.01);A组和B组嗜酸粒细胞密度和白介素5水平(-x±s)分别为(134.6±25.5)个/mm2、(48.2±13.9)pg/ml和(116.2±25.2)个/mm2、(40.8±7.8)pg/ml,均高于C组(16.7±2.7)个/mm2、(23.9±8.7)pg/ml(P值均＜0.05)和D组(13.4±4.9)个/mm2、(24.6±6.5)pg/ml(P值均＜0.05).结论 变应性鼻炎合并细菌性鼻窦炎造模成功.

Preliminary investigation into the allergic rhinitis complicated with acute bacterial sinusitis in mice

OBJECTIVE: To develop a mouse model of bacterial rhinosinusitis superposed on allergic rhinitis (AR), and to explore whether ongoing allergic rhinitis enhance the acute sinus infection and inflammation associated with Streptococcus pneumoniae (SP). METHODS: Fourty mice of C57BL6/J were randomly divided on average into 4 groups: A ovalbumin (OVA) + SP], B OVA + normal saline (NS)], C phosphate buffered solution (PBS) + SP] and D (PBS + NS). (1) Group A and B were sensitized by intraperitoneal injection with 200 microl (10%) OVA on days 1 through 9, and exposed to OVA (6%) intranasally on days 10 through 17, to induce allergic inflammation. OVA was replaced with PBS in group C and D in the same way. (2) Subsequently, group A and C were inoculated with SP intranasally on day 13, and NS was used in group B and D. On the 6th day after inoculation, mice were killed. Blood was collected from the orbital venous sinus after anesthesia. The heads were embedded with paraffin and serial sections were followed and stained with hematoxlin-eosin and toluidine blue (0.5%) for histological analysis and inflammation cells count. The number of polymorphounclear neutrophils (PMN) and eosinophils (EOS) per square millimeter of sinus mucosa were calculated by using a computer-aided special software under microscope. RESULTS: AR models were successfully established in 9 mice from group A and 8 from group B. Histologic examination of the sinus from group A and B revealed significant mucosal edema and dilated venules. The symptoms were mild in group C, and no symptom was observed in group D. PMN (x +/- s) in group A (139.3 +/- 26.5)/mm2 was significantly higher than that in group B (70.7 +/- 16.7)/mm2, C (63.0 +/- 14.7)/mm2 and D (40.2 +/- 14.1)/mm2 respectively (P < 0.01); EOS and serous IL-5 level in group A (134.6 +/- 25.5)/mm2, (48.2 +/- 13.9) pg/ml and B (116.2 +/- 25.2)/mm2, (40.8 +/- 7.8) pg/ml, were higher than that in group C (16.7 +/- 2.7)/mm2, (23.9 +/- 8.7) pg/ml (P < 0.05) and D (13.4 +/- 4.9)/mm2, (24.6 +/- 6.5) pg/ml (P < 0.05). CONCLUSIONS: The data demonstrate that an ongoing local allergic response augments bacterial infection in mice, and allergic sensitization alone without SP does not induce the sinus infection.