Parida Sonali, Mohapatra Amruta, Kar Banya, Mohanty Jyotirmaya, Sahoo Pramoda Kumar
ICAR-Central Institute of Freshwater Aquaculture, Kausalyaganga, Bhubaneswar 751 002, India.
Acta Parasitol. 2018 Mar 26;63(1):125-133. doi: 10.1515/ap-2018-0014.
The knowledge of mucosa-associated molecular events that occur during infections is scarce despite the well-established importance of mucus in fish immunity. Using qRT-PCR, we analyzed the immune gene expression patterns in mucus of Labeo rohita experimentally infected with an ectoparasite Argulus siamensis. Mucus samples were collected at 0 h, 12 h, 24 h, 3 d, 7 d, 15 d, and 30 d post challenge of L. rohita with metanauplii of A. siamensis. All interleukins studied herein (IL 6, IL 15, and IL 1β) showed significant upregulation of expression levels in mucus of A. siamensis-infected fish compared to control samples. Further, the expression levels of molecules involved in pathogen recognition, toll like receptor 22, and pathogen presentation, β2 microglobulin, were found to be significantly upregulated in experimental samples until 7 d post challenge compared to control samples. The upregulated expression of lysozyme G at all time points post infection indicated the early activation of acute phase responses in mucus of infected L. rohita. Moreover, the expression levels of natural killer cell enhancing factor B were found to be higher in infected fish than they were in the control fish. The early upregulation of the immune genes observed herein reinforces the role of mucus as the first line of defense against pathogenic assault; furthermore, it expands our understanding of mucosal-immune responses to A. siamensis infection, which can aid development of immunological interventions.
尽管黏液在鱼类免疫中具有公认的重要性，但关于感染期间发生的黏膜相关分子事件的了解却很少。我们使用qRT-PCR分析了实验感染体外寄生虫暹罗鲺的露斯塔野鲮黏液中的免疫基因表达模式。在露斯塔野鲮用暹罗鲺无节幼体攻击后的0小时、12小时、24小时、3天、7天、15天和30天收集黏液样本。与对照样本相比，本文研究的所有白细胞介素（IL 6、IL 15和IL 1β）在感染暹罗鲺的鱼类黏液中的表达水平均显著上调。此外，与对照样本相比，在攻击后7天内，实验样本中参与病原体识别的分子Toll样受体22和病原体呈递分子β2微球蛋白的表达水平显著上调。感染后所有时间点溶菌酶G的上调表达表明感染的露斯塔野鲮黏液中急性期反应的早期激活。此外，感染鱼类中自然杀伤细胞增强因子B的表达水平高于对照鱼类。本文观察到的免疫基因的早期上调强化了黏液作为抵御病原体攻击的第一道防线的作用；此外，它扩展了我们对暹罗鲺感染的黏膜免疫反应的理解，这有助于免疫干预措施的开发。
