日本血吸虫虫卵抗原Th1表位肽与不同佐剂联用对OVA诱导过敏性哮喘的抑制作用

The inhibitory effect of Th1 epitope peptide from schistosoma japonicum egg antigen with different adjuvant on OVA-induced allergic asthma in mice

目的观察日本血吸虫可溶性虫卵抗原SjP40蛋白中Th1表位肽分别与不同佐剂联用对OVA诱导的小鼠过敏性哮喘的抑制作用。方法 BABL/c雌性小鼠随机分为5组:正常对照组,OVA哮喘组,P25+弗氏不完全佐剂(Incomplete Freund's Adjuvant,IFA))组,P25+Alum组和P25单用组。将SjP40蛋白Th1表位多肽P25分别与IFA油佐剂,铝佐剂及PBS混合,于第0 d和14 d分别免疫BALB/c小鼠,于第7 d、21 d腹腔注射OVA致敏小鼠;第28～35 d用OVA滴鼻诱发小鼠哮喘,24 h后取小鼠肺组织,HE染色观察病理改变;收集肺泡灌洗液(BALF),涂片染色后计数嗜酸性粒细胞;采用ELISA法检测血清OVA特异性IgE及BALF和脾细胞培养上清液中IL-4和IFN-水平。结果肺组织病理评分P25+IFA组为7.80±1.23,P25+铝佐剂组为9.07±0.97,与OVA哮喘组13.50±1.04比较差异有统计学意义(P<0.05或P<0.01);P25+IFA组支气管上皮粘液分泌面积比例为(15.8±2.23)%,P25+铝佐剂组为(21.07±1.37)%,与OVA哮喘组(43.5±0.84)%比较差异有统计学意义(P<0.05或P<0.01);P25 IFA组和P25铝佐剂组嗜酸性粒细胞数目与OVA哮喘组比较,差异有统计学意义(P<0.01);P25 IFA组和P25铝佐剂组血清OVA特异性IgE水平与OVA哮喘组比较,差异有统计学意义(P<0.05)。结论 SjP40蛋白中Th1表位肽P25与IFA佐剂及铝佐剂联用对OVA诱导的小鼠过敏性哮喘具有抑制作用,以IFA佐剂效果更佳。

Objective To explore the inhibitory effect of Th1 epitope peptide P25 from Schistosoma japonicum egg antigen with different adjuvant on allergic asthma in BALB/c mice.Methods Female BALB/c mice were randomly divided into five groups: Normal group,P25 + IFA group,P25 + Alum group,P25 group and OVA only group.Mice were immunized with P25 combined with IFA,Alum or PBS respectively on day 0 and day 14.OVA combined with Alum were injected in mice on day 7 and day 21.Mice were challenged with OVA intranasally daily from day 28 to day 35.The pathological change of lung tissues was observed after HE staining and measured by Underwood Score.Bronchoalveolar lavage fluid(BALF) was obtained and the eosinophils in BALF were counted after Wright’s-Giemsa’s staining.The expression levels of serum OVA-specific IgE and various cytokines(IL-4,IFN-) in BALF were examined by ELISA.Results It was showed that pulmonary inflammation diminished in mice in P25 + IFA and P25+Alum group compared with OVA only group.Underwood Score in P25 + IFA and P25 + Alum group were 7.80±1.23 and 9.07±0.97,respectively,while score in OVA group was 13.50±1.04.The difference in Underwood Score was statistically significant(P<0.05);The mucus secreting area ratio of bronchial epithelium was calculated after AB-PAS staining.The ratio in P25+IFA group and P25+Alum group were(15.8±2.23)% and(21.07±1.37)%,respectively,which was significant difference compared with OVA only group(P<0.05).In addition,lower eosinophil counts in BALF were detected in P25 + IFA group and P25 + Alum group,with significant difference compared to OVA only group(P<0.01).On the other hand,the levels of OVA-specific IgE decreased in P25 + IFA group and P25 + Alum group,with significant difference compared to OVA only group(P<0.05).Conclusion Th1 epitope peptide P25 from Schistosoma japonicum egg antigen combined with IFA and Alum adjuvant could show inhibitory effect of on OVA induced allergic asthma in BALB/c mice.