Clinical Division of Fish Medicine, Department for Farm Animals and Veterinary Public Health, University of Veterinary Medicine Vienna, Vienna, Austria.
Scottish Fish Immunology Research Centre, School of Biological Sciences, University of Aberdeen, Aberdeen, Scotland, United Kingdom.
PLoS One. 2020 Jun 15;15(6):e0234479. doi: 10.1371/journal.pone.0234479. eCollection 2020.
There are differences in disease susceptibility to whirling disease (WD) among strains of rainbow trout. The North American strain Trout Lodge (TL) is highly susceptible, whereas the German Hofer (HO) strain is more resistant. The suppressor of cytokine signaling (SOCS) proteins are key in inhibiting cytokine signaling. Their role in modulating the immune response against whirling disease is not completely clear. This study aimed at investigating the transcriptional response of SOCS1 and SOCS3 genes to Myxobolus cerebralis along with that of several upstream regulators and immune response genes. M. cerebralis induced the expression of SOCS1, the IL-6-dependent SOCS3, the anti-inflammatory cytokine IL-10 and the Treg associated transcription factor FOXP3 in TL fish at multiple time points, which likely caused a restricted STAT1 and STAT3 activity affecting the Th17/Treg17 balance. The expression of SOCS1 and the IL-6-dependent SOCS3 was induced constraining the activation of STAT1 and STAT3 in TL fish, thereby causing Th17/Treg17 imbalance and leaving the fish unable to establish a protective immune response against M. cerebralis or control inflammatory reactions increasing susceptibility to WD. Conversely, in HO fish, the expression of SOCS1 and SOCS3 was restrained, whereas the expression of STAT1 and IL-23-mediated STAT3 was induced potentially enabling more controlled immune responses, accelerating parasite clearance and elevating resistance. The induced expression of STAT1 and IL-23-mediated STAT3 likely maintained a successful Th17/Treg17 balance and enabled fish to promote effective immune responses favouring resistance against WD. The results provide insights into the role of SOCS1 and SOCS3 in regulating the activation and magnitude of host immunity in rainbow trout, which may help us understand the mechanisms that underlie the variation in resistance to WD.
旋转病(WD)在虹鳟鱼不同品系间的易感性存在差异。北美品系特劳特洛奇(TL)高度易感,而德国霍费尔(HO)品系则更具抗性。细胞因子信号抑制物(SOCS)蛋白在抑制细胞因子信号方面起着关键作用。它们在调节对 WD 免疫反应中的作用尚不完全清楚。本研究旨在研究 SOCS1 和 SOCS3 基因对粘孢子虫(Myxobolus cerebralis)的转录反应,以及几个上游调节剂和免疫反应基因。在多个时间点,M. cerebralis 诱导 TL 鱼中 SOCS1、IL-6 依赖性 SOCS3、抗炎细胞因子 IL-10 和与 Treg 相关的转录因子 FOXP3 的表达,这可能导致 STAT1 和 STAT3 活性受限,影响 Th17/Treg17 平衡。SOCS1 和 IL-6 依赖性 SOCS3 的表达诱导限制了 STAT1 和 STAT3 在 TL 鱼中的激活,从而导致 Th17/Treg17 失衡,使鱼无法对 M. cerebralis 建立保护性免疫反应或控制炎症反应,增加对 WD 的易感性。相反,在 HO 鱼中,SOCS1 和 SOCS3 的表达受到限制,而 STAT1 和 IL-23 介导的 STAT3 的表达则被诱导,这可能使免疫反应更受控制,加速寄生虫清除,并提高抗性。STAT1 和 IL-23 介导的 STAT3 的诱导表达可能维持了成功的 Th17/Treg17 平衡,并使鱼能够促进有效的免疫反应,有利于对 WD 的抗性。这些结果提供了 SOCS1 和 SOCS3 在调节虹鳟鱼宿主免疫激活和幅度方面的作用的见解,这可能有助于我们理解对 WD 抗性变化的机制。