Mathew Marina, Waugh Courtney, Beagley Kenneth W, Timms Peter, Polkinghorne Adam
Institute of Health & Biomedical Innovation, Queensland University of Technology, 60 Musk Avenue, Kelvin Grove 4059, Brisbane, Australia.
Institute of Health & Biomedical Innovation, Queensland University of Technology, 60 Musk Avenue, Kelvin Grove 4059, Brisbane, Australia; Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, 90 Sippy Downs Dr, Sippy Downs 4558, QLD, Australia.
Dev Comp Immunol. 2014 Oct;46(2):423-9. doi: 10.1016/j.dci.2014.05.015. Epub 2014 Jun 8.
The koala (Phascolarctos cinereus) is an iconic Australian marsupial species that is facing many threats to its survival. Chlamydia pecorum infections are a significant contributor to this ongoing decline. A major limiting factor in our ability to manage and control chlamydial disease in koalas is a limited understanding of the koala's cell-mediated immune response to infections by this bacterial pathogen. To identify immunological markers associated with chlamydial infection and disease in koalas, we used koala-specific Quantitative Real Time PCR (qrtPCR) assays to profile the cytokine responses of Peripheral Blood Mononuclear Cells (PBMCs) collected from 41 koalas with different stages of chlamydial disease. Target cytokines included the principal Th1 (Interferon gamma; IFNγ), Th2 (Interleukin 10; IL10), and pro-inflammatory cytokines (Tumor Necrosis Factor alpha; TNFα). A novel koala-specific IL17A qrtPCR assay was also developed as part of this study to quantitate the gene expression of this Th17 cytokine in koalas. A statistically significant higher IL17A gene expression was observed in animals with current chlamydial disease compared to animals with asymptomatic chlamydial infection. A modest up-regulation of pro-inflammatory cytokines, such as TNFα and IFNγ, was also observed in these animals with signs of current chlamydial disease. IL10 gene expression was not evident in the majority of animals from both groups. Future longitudinal studies are now required to confirm the role played by cytokines in pathology and/or protection against C. pecorum infection in the koala.
考拉（树袋熊，Phascolarctos cinereus）是澳大利亚标志性的有袋类动物，其生存面临诸多威胁。感染考拉衣原体（Chlamydia pecorum）是导致其数量持续减少的一个重要因素。我们管理和控制考拉衣原体疾病能力的一个主要限制因素是，对考拉针对这种细菌病原体感染的细胞介导免疫反应了解有限。为了确定与考拉衣原体感染和疾病相关的免疫标志物，我们使用考拉特异性定量实时聚合酶链反应（qrtPCR）检测方法，对从41只处于不同衣原体疾病阶段的考拉采集的外周血单核细胞（PBMCs）的细胞因子反应进行了分析。检测的目标细胞因子包括主要的Th1（干扰素γ；IFNγ）、Th2（白细胞介素10；IL10）和促炎细胞因子（肿瘤坏死因子α；TNFα）。作为本研究的一部分，还开发了一种新型的考拉特异性IL17A qrtPCR检测方法，以定量该Th17细胞因子在考拉中的基因表达。与无症状衣原体感染的动物相比，在患有当前衣原体疾病的动物中观察到IL17A基因表达有统计学意义的显著升高。在这些有当前衣原体疾病症状的动物中，还观察到促炎细胞因子如TNFα和IFNγ有适度上调。两组中的大多数动物均未明显检测到IL10基因表达。现在需要进一步的纵向研究来确认细胞因子在考拉病理学和/或抵抗考拉衣原体感染中的作用。
