Drake K Kristina, Aiello Christina M, Bowen Lizabeth, Lewison Rebecca L, Esque Todd C, Nussear Kenneth E, Waters Shannon C, Hudson Peter J
Western Ecological Research Center U.S. Geological Survey Henderson Nevada.
Department of Biology San Diego State University San Diego California.
Ecol Evol. 2019 Feb 18;9(5):2516-2534. doi: 10.1002/ece3.4897. eCollection 2019 Mar.
Immune function plays an important role in an animal's defense against infectious disease. In reptiles, immune responses may be complex and counterintuitive, and diagnostic tools used to identify infection, such as induced antibody responses are limited. Recent studies using gene transcription profiling in tortoises have proven useful in identifying immune responses to various intrinsic and extrinsic stressors. As part of a larger experiment with Mojave desert tortoises (), we facilitated the transmission of the pathogenic bacteria, (Myag), to naïve adults and measured innate and induced immune reactions over time. Specifically, we evaluated clinical condition, presence of Myag in the nasal/oral cavity, induced antibody responses specific to Myag, and measured molecular reactions (gene transcript profiles) in 15 captive tortoises classified as naïve, exposed, or infected and 14 wild tortoises for comparison. Myag was confirmed inside the nasal/oral cavity in exposed tortoises within 30-60 days of introduction to infected animals, yet we did not detect Myag specific induced antibody responses in these individuals until 420-595 days post exposure. Surprisingly, we found no overall differences in the gene transcript profiles between our experimental treatment groups throughout this study. This work highlights the complexities in assessing immune function and diagnosing pathogen related infections in tortoises and other reptiles.
免疫功能在动物抵御传染病中发挥着重要作用。在爬行动物中，免疫反应可能很复杂且有违直觉，用于识别感染的诊断工具，如诱导抗体反应，是有限的。最近在陆龟中使用基因转录谱分析的研究已证明有助于识别对各种内在和外在应激源的免疫反应。作为对莫哈韦沙漠陆龟进行的一项更大规模实验的一部分，我们促使病原菌（Myag）传播给未接触过该菌的成年陆龟，并随时间测量先天和诱导免疫反应。具体而言，我们评估了临床状况、鼻腔/口腔中Myag的存在情况、针对Myag的诱导抗体反应，并在15只被分类为未接触过、接触过或感染的圈养陆龟以及14只野生陆龟中测量了分子反应（基因转录谱）以作比较。在将接触过感染动物的陆龟引入后的30 - 60天内，在其鼻腔/口腔内确认发现了Myag，但直到接触后420 - 595天，我们才在这些个体中检测到针对Myag的特异性诱导抗体反应。令人惊讶的是，在整个研究过程中，我们发现实验处理组之间的基因转录谱没有总体差异。这项工作凸显了评估陆龟和其他爬行动物免疫功能以及诊断与病原体相关感染的复杂性。
