School of Environment and Science, Griffith University, Southport, Queensland, 4222, Australia; Centre for Planetary Health and Food Security, Griffith University, Southport, Queensland, 4222, Australia; Faculty of Science and Engineering, Southern Cross University, Lismore, New South Wales, 2480, Australia.
School of Environment and Science, Griffith University, Southport, Queensland, 4222, Australia; Australian Rivers Institute, Griffith University, Southport, Queensland, 4222, Australia.
Dev Comp Immunol. 2022 Nov;136:104510. doi: 10.1016/j.dci.2022.104510. Epub 2022 Aug 17.
Amphibians are among the vertebrate groups suffering great losses of biodiversity due to a variety of causes including diseases, such as chytridiomycosis (caused by the fungal pathogens Batrachochytrium dendrobatidis and B. salamandrivorans). The amphibian metamorphic period has been identified as being particularly vulnerable to chytridiomycosis, with dramatic physiological and immunological reorganisation likely contributing to this vulnerability. Here, we overview the processes behind these changes at metamorphosis and then perform a systematic literature review to capture the breadth of empirical research performed over the last two decades on the metamorphic immune response. We found that few studies focused specifically on the immune response during the peri-metamorphic stages of amphibian development and fewer still on the implications of their findings with respect to chytridiomycosis. We recommend future studies consider components of the immune system that are currently under-represented in the literature on amphibian metamorphosis, particularly pathogen recognition pathways. Although logistically challenging, we suggest varying the timing of exposure to Bd across metamorphosis to examine the relative importance of pathogen evasion, suppression or dysregulation of the immune system. We also suggest elucidating the underlying mechanisms of the increased susceptibility to chytridiomycosis at metamorphosis and the associated implications for population persistence. For species that overlap a distribution where Bd/Bsal are now endemic, we recommend a greater focus on management strategies that consider the important peri-metamorphic period.
两栖动物是由于多种原因（包括疾病，如蛙壶菌病（由真菌病原体蛙壶菌和蛙球虫引起））而导致生物多样性大量丧失的脊椎动物群体之一。两栖动物的变态期被认为特别容易受到蛙壶菌病的影响，这种脆弱性可能与剧烈的生理和免疫重组有关。在这里，我们概述了变态过程中这些变化背后的过程，然后进行了系统的文献回顾，以捕捉过去二十年中在两栖动物变态免疫反应方面进行的广泛实证研究。我们发现，很少有研究专门关注两栖动物发育的变态前期阶段的免疫反应，更少的研究关注它们的发现对蛙壶菌病的影响。我们建议未来的研究考虑目前在关于两栖动物变态的文献中代表性不足的免疫系统成分，特别是病原体识别途径。尽管在操作上具有挑战性，但我们建议在变态过程中改变接触 Bd 的时间，以检查逃避病原体、抑制或免疫失调的相对重要性。我们还建议阐明在变态时对蛙壶菌病易感性增加的潜在机制及其对种群生存的相关影响。对于分布范围与 Bd/Bsal 现在共存的物种，我们建议更加关注考虑重要的变态前期阶段的管理策略。
