Kirtsreesakul Virat, Luxameechanporn Thongchai, Klemens James J, Thompson Kenneth, Naclerio Robert M
Department of Surgery, Section of Otolaryngology-Head and Neck Surgery and Pathology, University of Chicago, Chicago, IL 60637, USA.
Arch Otolaryngol Head Neck Surg. 2006 Oct;132(10):1102-8. doi: 10.1001/archotol.132.10.1102.
To study the importance of ongoing allergen exposure and TH1/TH2 genetic background in augmented bacterial and inflammatory responses in allergic and infected mice.
BALB/c and C57BL/6 mice were made allergic to ovalbumin. After 1 day of intranasal allergen exposure, they were inoculated intranasally with Streptococcus pneumoniae. The numbers of bacteria and inflammatory cells in the sinuses were determined, and nasal responsiveness to histamine was assessed.
Infected BALB/c and C57BL/6 mice that received ongoing ovalbumin challenge following intraperitoneal sensitization showed significantly greater bacterial load and phagocyte level compared with the infected-only mice. Differences were diminished after the allergen challenge was stopped. Allergic and infected C57BL/6 mice showed fewer bacteria and phagocytes compared with the allergic and infected BALB/c mice. Surprisingly, in contrast to the nonallergenic C57BL/6 mice, the infected BALB/c mice showed a larger number of bacteria 28 days after infection.
Ongoing allergic reaction augments bacterial load in both BALB/c and C57BL/6 mice and induces nasal hyperreactivity to histamine. Allergic and infected C57BL/6 mice show less allergic inflammation and bacterial load compared with allergic and infected BALB/c mice. Stopping allergen exposure reduces the response. Infected BALB/c mice, which favor a TH2 response, were less able to clear infection than C57BL/6 mice, which favor a TH1 response. Inflammation and bacterial load are affected by genetic background of mice and ongoing allergen stimulation.
研究持续的变应原暴露和TH1/TH2遗传背景在变应性和感染小鼠中增强细菌及炎症反应方面的重要性。
将BALB/c和C57BL/6小鼠制成对卵清蛋白过敏。在鼻内暴露变应原1天后，经鼻接种肺炎链球菌。测定鼻窦内细菌和炎症细胞数量，并评估鼻对组胺的反应性。
与仅感染的小鼠相比，经腹腔致敏后持续接受卵清蛋白激发的感染BALB/c和C57BL/6小鼠显示出显著更高的细菌载量和吞噬细胞水平。变应原激发停止后差异减小。与变应性和感染的BALB/c小鼠相比，变应性和感染的C57BL/6小鼠的细菌和吞噬细胞较少。令人惊讶的是，与无变应性的C57BL/6小鼠不同，感染的BALB/c小鼠在感染后28天显示出更多的细菌。
持续的变应性反应增加BALB/c和C57BL/6小鼠的细菌载量，并诱导鼻对组胺的高反应性。与变应性和感染的BALB/c小鼠相比，变应性和感染的C57BL/6小鼠的变应性炎症和细菌载量较少。停止变应原暴露可降低反应。倾向于TH2反应的感染BALB/c小鼠比倾向于TH1反应的C57BL/6小鼠清除感染的能力更弱。炎症和细菌载量受小鼠遗传背景和持续变应原刺激的影响。
