Viney Mark, Riley Eleanor M
School of Biological Sciences, University of Bristol, Bristol, United Kingdom.
Department of Immunology and Infection, London School of Hygiene and Tropical Medicine, London, United Kingdom.
Front Immunol. 2017 Nov 14;8:1481. doi: 10.3389/fimmu.2017.01481. eCollection 2017.
Wild animals' immune responses contribute to their evolutionary fitness. These responses are moulded by selection to be appropriate to the actual antigenic environment in which the animals live, but without imposing an excessive energetic demand which compromises other component of fitness. But, exactly what these responses are, and how they compare with those of laboratory animals, has been little studied. Here, we review the very small number of published studies of immune responses of wild rodents, finding general agreement that their humoral (antibody) responses are highly elevated when compared with those of laboratory animals, and that wild rodents' cellular immune system reveals extensive antigenic exposure. In contrast, proliferative and cytokine responses of -stimulated immune cells of wild rodents are typically depressed compared with those of laboratory animals. Collectively, these responses are appropriate to wild animals' lives, because the elevated responses reflect the cumulative exposure to infection, while the depressed proliferative and cytokine responses are indicative of effective immune homeostasis that minimizes immunopathology. A more comprehensive understanding of the immune ecology of wild animals requires (i) understanding the antigenic load to which wild animals are exposed, and identification of any key antigens that mould the immune repertoire, (ii) identifying immunoregulatory processes of wild animals and the events that induce them, and (iii) understanding the actual resource state of wild animals, and the immunological consequences that flow from this. Together, by extending studies of wild rodents, particularly addressing these questions (while drawing on our immunological understanding of laboratory animals), we will be better able to understand how rodents' immune responses contribute to their fitness in the wild.
野生动物的免疫反应有助于其进化适应性。这些反应通过选择塑造，以适应动物生存的实际抗原环境，但不会带来过度的能量需求，以免影响适应性的其他方面。但是，这些反应究竟是什么，以及它们与实验动物的反应相比如何，却鲜有研究。在此，我们回顾了极少数已发表的关于野生啮齿动物免疫反应的研究，发现普遍的共识是，与实验动物相比，它们的体液（抗体）反应高度增强，并且野生啮齿动物的细胞免疫系统显示出广泛的抗原暴露。相比之下，与实验动物相比，野生啮齿动物受刺激的免疫细胞的增殖和细胞因子反应通常受到抑制。总体而言，这些反应与野生动物的生活相适应，因为增强的反应反映了对感染的累积暴露，而受抑制的增殖和细胞因子反应表明有效的免疫稳态，可将免疫病理学降至最低。要更全面地了解野生动物的免疫生态学，需要：（i）了解野生动物所接触的抗原负荷，并识别塑造免疫库的任何关键抗原；（ii）识别野生动物的免疫调节过程及其诱导事件；（iii）了解野生动物的实际资源状况及其产生的免疫学后果。总之，通过扩展对野生啮齿动物的研究，特别是解决这些问题（同时借鉴我们对实验动物的免疫学理解），我们将能够更好地理解啮齿动物的免疫反应如何在野外环境中对其适应性做出贡献。
