不同剂量外源性白介素17A干预对变应性鼻炎小鼠气道炎症的影响

Dose-dependent effects of exogenous IL-17A on airway inflammatory responses in mice with allergic rhinitis

目的探讨不同剂量的外源性白细胞介素17A(IL-17A)干预对变应性鼻炎小鼠气道炎症的影响。方法将48只小鼠采用随机数字表法分为A、B、C、D、E、F组,每组8只。分别于第0、7、14天将溶于50μL生理盐水的20μg卵清蛋白(OVA)加2 mg铝佐剂腹腔注射处理D、E及F组小鼠,间隔7 d,于第22天开始鼻腔激发,每天每侧鼻孔各滴入OVA 10μL,连续7 d。D、E及F组小鼠于每次OVA鼻腔激发前1 h分别给予生理盐水、IL-17A蛋白100 ng、IL-17A蛋白500 ng滴鼻,A、B及C组小鼠于相同时点予等量生理盐水腹腔注射并滴鼻,B、C组小鼠于每次生理盐水鼻腔激发前1 h分别给予IL-17A蛋白100 ng、IL-17A蛋白500 ng滴鼻。所有小鼠于最后一次激发后评估鼻部症状学变化,Diff-Quik染色观察鼻腔灌洗液(NLF)中嗜酸性粒细胞浸润情况,ELISA法检测血清及NLF中IL-6、IL-10水平,鼻黏膜组织行甲苯胺蓝染色观察肥大细胞数。结果 4周末D组所有小鼠症状学评分均>5分,造模成功。A、B、C、D、E及F组症状学评分分别为1.5(1.0～2.8)、2.0(1.0～3.0)、2.5(2.0～3.0)、7.0(6.3～8.0)、3.0(2.3～3.8)及8.0(7.0～8.8)分。E组小鼠挠鼻及喷嚏次数少于D组(H=21.375,P=0.033; H=20.250,P=0.049)。D组小鼠血清及NLF中IL-6水平高于A组(H=25.750,P=0.004; H=20.688,P=0.047),IL-10水平低于A组(H=22.875,P=0.016; H=20.625,P=0.048)。E组小鼠血清及NLF中IL-6水平与A组相比差异无统计学意义(H=19.875,P=0.068; H=8.125,P>0.999)。E组小鼠血清中IL-10水平高于D组(H=27.062,P=0.002)。F组小鼠血清及NLF中IL-6水平高于A组(H=22.250,P=0.008; H=28.688,P=0.001)。F组小鼠血清及NLF中IL-10水平与D组相比差异无统计学意义(H=13.062,P=0.930; H=0.500,P>0.999)。C组小鼠NLF中嗜酸性粒细胞数高于A组(H=20.688,P=0.047)。E组小鼠NLF中嗜酸性粒细胞数低于D组(H=21.188,P=0.037)。F组小鼠NLF中嗜酸性粒细胞数与D组相比差异无统计学意义(H=2.875,P>0.999)。D组小鼠鼻黏膜组织中肥大细胞数与A组相比增多(H=27.188,P=0.002)。E组小鼠鼻黏膜组织中肥大细胞数少于D组(H=20.938,P=0.042)。F组小鼠鼻黏膜组织中肥大细胞数与D相比差异无统计学意义(H=1.188,P>0.999)。结论 500 ng的外源性IL-17A能促使小鼠鼻腔嗜酸性粒细胞募集,100 ng的外源性IL-17A对变应性鼻炎小鼠模型气道炎症有保护作用。

Objective To evaluate the effects of different doses of exogenous Interleukin-17 A( IL-17 A) on airway inflammatory responses in mice with allergic rhinitis. Methods Forty-eight BALB/c female mice were assigned randomly to six groups( A,B,C,D,E,and F),with eight mice per group. Groups D,E,and F received intraperitoneal OVA injection and nasal challenge,normal saline( NS),and different doses of IL-17 A( 100 ng and 500 ng) one hour before nasal challenge,respectively. Groups A,B,and C received intraperitoneal NS injection and nasal challenge,NS,and different doses of IL-17 A( 100 ng and 500 ng) one hour before nasal challenge,respectively. Nasal symptoms were assessed at 4 weeks. Serum,nasal lavage fluid( NLF),and nasal tissue werecollected. Eosinophils in NLF were measured using Diff-Quik staining. IL-6 and IL-10 levels in serum and NLF were measured using enzyme-linked immunosorbent assay( ELISA). Mast cells in nasal mucosa were measured using toluidine blue staining. Results All mice in group D had a symptom score of greater than five points,demonstrating that the model was successful. Groups A,B,C,D,E,and F had average scores of 1.5( 1.0-2.8),2.0( 1.0-3.0),2.5( 2.0-3.0),7.0( 6.3-8.0),3.0( 2.3-3.8),and 8.0( 7.0-8.8),respectively. Rubbing times and number of sneezes were lower in group E than in group D( H = 21.375,P = 0.033,H =20.250,P= 0.049). Levels of IL-6 in the serum and NLF were higher in group D than in group A( H = 25.750,P = 0.004; H =20.688,P= 0.047). IL-10 levels in the serum and NLF were lower in group D than in group A( H = 22.875,P= 0.016; H = 20.625,P= 0.048). There were no significant differences in IL-6 levels in the serum and NLF between group E and group A( H = 19.875,P= 0.068; H = 8.125,P>0.999). IL-10 levels in the serum were higher in group E than in group D( H = 27.062,P= 0.002). IL-6 levels in the serum and NLF were higher in group F than in group A( H = 22.250,P= 0.008,H = 28.688,P= 0.001). There were no significant differences in IL-10 levels in the serum and NLF between group F and group D( H = 13.062,P= 0.930; H = 0.500,P>0.999). Eosinophils in the NLF were more abundant in group C than in group A( H = 20.688,P = 0.047). The number of eosinophils in group E was significantly lower than that in group D( H = 21.188,P = 0.037). There was no significant difference in the number of eosinophils in group F compared with that in group D( H = 2.875,P>0.999). Mast cells in the nasal mucosa were more abundant in group D than in group A( H = 27.188,P= 0.002). The number of mast cells in the nasal mucosa was lower in group E than in group D( H = 20.938,P= 0.042). There was no significant difference in the number of mast cells between group F and group D( H = 1.188,P>0.999). Conclusion 500 ng of exogenous IL-17 A led to a modest proinflammatory effect in normal mice. Treatment with 100 ng exogenous IL-17 A in mice with allergic rhinitis can protect against allergic airway inflammation.