Animal Health Research Center (CISA-INIA), Madrid, Spain.
Scottish Fish Immunology Research Centre, School of Biological Sciences, University of Aberdeen, Aberdeen, United Kingdom.
Front Immunol. 2020 Jul 9;11:1494. doi: 10.3389/fimmu.2020.01494. eCollection 2020.
Interferons (IFNs) orchestrate antiviral responses in jawed vertebrates and can be classified into three types based on different aspects of their genomic organization, structure and receptors through which they signal and function. Generally, type I and type III IFNs include cytokines that directly induce an antiviral response, whereas type II IFNs are well-known for their immunomodulatory role during viral infections. In mammals, type I IFNs have been shown to also regulate many aspects of B cell development and differentiation. Yet, these functions have been only faintly investigated for teleost IFNs. Thus, in the current study, we have examined the effects of a model type I rainbow trout IFN molecule (IFNa) on blood naïve (IgMIgD) B cells, comparing them to those exerted by type II IFN (IFNγ). Our results demonstrate that IFNa increases the survival of naïve rainbow trout B cells, in the absence of lymphoproliferative effects, by rescuing them from spontaneous apoptosis. Additionally, IFNa increased the phagocytic capacity of blood IgMIgD B cells and augmented the number of IgM-secreting cells in blood leukocyte cultures. IFNγ, on the other hand, had only minor effects up-regulating IgM secretion, whereas it increased the phagocytic capacity of IgM cells in the cultures. Finally, given the recent identification of 9 genes in rainbow trout, we have also established which of these genes were transcriptionally regulated in blood naïve B cells in response to IFNa. This study points to a previously undescribed role for teleost type I IFNs in the regulation of B cell responses.
干扰素（IFNs）在有颌脊椎动物中协调抗病毒反应，根据其基因组组织、结构和受体的不同，可以分为三类，这些受体是它们信号转导和发挥功能的途径。一般来说，I 型和 III 型 IFNs 包括可直接诱导抗病毒反应的细胞因子，而 II 型 IFNs 在病毒感染期间的免疫调节作用是众所周知的。在哺乳动物中，已经表明 I 型 IFNs 还调节 B 细胞发育和分化的许多方面。然而，这些功能在硬骨鱼类 IFNs 中仅被微弱地研究过。因此，在本研究中，我们研究了模型 I 型虹鳟鱼 IFN 分子（IFNa）对血液幼稚（IgMIgD）B 细胞的影响，并将其与 II 型 IFN（IFNγ）进行了比较。我们的结果表明，IFNa 通过挽救自发凋亡来增加幼稚虹鳟鱼 B 细胞的存活率，而不产生淋巴增生作用。此外，IFNa 增加了血液 IgMIgD B 细胞的吞噬能力，并增加了血液白细胞培养中 IgM 分泌细胞的数量。另一方面，IFNγ 对 IgM 分泌的上调作用较小，而在培养物中增加了 IgM 细胞的吞噬能力。最后，鉴于最近在虹鳟鱼中鉴定出 9 个基因，我们还确定了这些基因中哪些基因在血液幼稚 B 细胞中对 IFNa 有转录调节作用。本研究指出了硬骨鱼类 I 型 IFNs 在调节 B 细胞反应方面的一个以前未描述的作用。
