Sur Sayantan, Tiwari Jyoti, Malik Shalie, Stevenson Tyler
School of Biodiversity, One Health & Veterinary Medicine, University of Glasgow, Glasgow G61 1QH, UK.
Department of Zoology, University of Lucknow, Lucknow, Uttar Pradesh 226007, India.
Philos Trans R Soc Lond B Biol Sci. 2025 Jan 23;380(1918):20230507. doi: 10.1098/rstb.2023.0507.
Birds have evolved seasonal adaptations in multiple aspects of the innate and adaptive immune systems. Seasonal immunological adaptations are crucial for survival in harsh environmental conditions and in response to increased prevalence of acute and chronic diseases. Similar to other vertebrates, birds exhibit remarkable plasticity in cytokine production, chemotaxis, phagocytosis and inflammation across the year. In this review, we provide a comparative perspective on seasonal rhythms in bird immune function. We describe advances in our understanding of annual changes in immune cells and responses to innate and adaptive immune challenges. Then, the role of glucocorticoids, sex steroids, thyroid hormones (THs) and melatonin to act as immunomodulators is described. We then discuss the impact of a major and emerging disease, the high pathogenicity avian influenza, as one of the most critical seasonal diseases with significant implications for poultry and wild bird populations. The review identifies the need to enhance our knowledge of annual rhythms in immune cells and tissues in birds, at molecular, cellular and hormonal levels across the year. Moreover, there is a significant absence of information on sex-specific seasonal variation in immune function. Understanding seasonal immune system dynamics will aid in addressing the negative impacts of pathogenic diseases, minimize global economic losses and aid conservation efforts.This article is part of the Theo Murphy meeting issue 'Circadian rhythms in infection and immunity'.
鸟类在先天免疫系统和适应性免疫系统的多个方面进化出了季节性适应机制。季节性免疫适应对于在恶劣环境条件下生存以及应对急慢性疾病患病率上升至关重要。与其他脊椎动物类似，鸟类在全年的细胞因子产生、趋化作用、吞噬作用和炎症反应方面表现出显著的可塑性。在这篇综述中，我们提供了关于鸟类免疫功能季节性节律的比较观点。我们描述了在理解免疫细胞的年度变化以及对先天免疫和适应性免疫挑战的反应方面取得的进展。然后，描述了糖皮质激素、性类固醇、甲状腺激素（THs）和褪黑素作为免疫调节剂的作用。接着，我们讨论了一种主要的新兴疾病——高致病性禽流感的影响，它是对家禽和野生鸟类种群具有重大影响的最关键季节性疾病之一。这篇综述指出，有必要在分子、细胞和激素水平上，加强我们对鸟类免疫细胞和组织全年年度节律的认识。此外，关于免疫功能的性别特异性季节性变化，目前存在大量信息空白。了解季节性免疫系统动态将有助于应对致病疾病的负面影响，将全球经济损失降至最低，并有助于保护工作。本文是西奥·墨菲会议议题“感染与免疫中的昼夜节律”的一部分。
