Shaughnessy Ronan G, Meade Kieran G, Cahalane Sarah, Allan Brenda, Reiman Carla, Callanan John J, O'Farrelly Cliona
Comparative Immunology Group, School of Biochemistry and Immunology, Trinity College, Dublin 2, Ireland.
Vet Immunol Immunopathol. 2009 Dec 15;132(2-4):191-8. doi: 10.1016/j.vetimm.2009.06.007. Epub 2009 Jun 21.
Salmonella enterica serovar Typhimurium and Campylobacter jejuni are major human pathogens, yet colonise chickens without causing pathology. The aim of this study was to compare intestinal innate immune responses to both bacterial species, in a 4-week-old broiler chicken model. Challenged and control birds were sacrificed and tissue samples taken for histopathology and RNA extraction. No significant clinical or pathological changes were observed in response to infection with either bacterial species. Expression of selected genes involved in pathogen detection and the innate immune response were profiled in caecal tissues by quantitative real-time PCR. TLR4 and TLR21 gene expression was transiently increased in response to both bacterial species (P<0.05). Significant increases in TLR5 and TLR15 gene expression were detected in response to S. Typhimurium but not to C. jejuni. Transient increases of proinflammatory cytokine (IL6 and IFNG) and chemokine (IL8 and K60) genes increased as early as 6h in response to S. Typhimurium. Minimal cytokine gene expression was detected in response to C. jejuni after 20h. IL8 gene expression however, was significantly increased by 24-fold (P<0.01). The differential expression profiles of innate immune genes in both infection models shed light on the tailored responses of the host immune system to specific microbes. It is further evidence that innate regulation of these responses is an important prerequisite to preventing development of disease.
肠炎沙门氏菌鼠伤寒血清型和空肠弯曲菌是主要的人类病原体，但它们在鸡体内定殖却不会引发病变。本研究的目的是在4周龄的肉鸡模型中比较对这两种细菌的肠道固有免疫反应。对受挑战和对照的鸡进行宰杀，并采集组织样本用于组织病理学检查和RNA提取。感染任何一种细菌均未观察到明显的临床或病理变化。通过定量实时PCR分析盲肠组织中参与病原体检测和固有免疫反应的选定基因的表达。TLR4和TLR21基因的表达在对两种细菌的反应中均短暂增加（P<0.05）。检测到TLR5和TLR15基因的表达在对鼠伤寒沙门氏菌的反应中有显著增加，但对空肠弯曲菌没有。促炎细胞因子（IL6和IFNG）和趋化因子（IL8和K60）基因的短暂增加在对鼠伤寒沙门氏菌的反应中早在6小时就出现了。在20小时后，对空肠弯曲菌的反应中检测到的细胞因子基因表达最少。然而，IL8基因的表达显著增加了24倍（P<0.01）。两种感染模型中固有免疫基因的差异表达谱揭示了宿主免疫系统对特定微生物的适应性反应。这进一步证明了这些反应的固有调节是预防疾病发生的重要前提。
