Discovery of immunoglobulin T in Nile tilapia (Oreochromis niloticus): A potential molecular marker to understand mucosal immunity in this species
Discovery of immunoglobulin T in Nile tilapia (Oreochromis niloticus): A potential molecular marker to understand mucosal immunity in this species
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DOI：
10.1016/j.dci.2018.07.013
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发表时间：
2018-11-01
影响因子：
2.9
通讯作者：
Pablo Estrada, Mario
中科院分区：
文献类型：
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作者：
Velazquez, Janet;Acosta, Jannel;Pablo Estrada, Mario
免疫球蛋白分子通过保护生物体免受多种病原体的侵害，在所有有颌脊椎动物的免疫防御系统中发挥着重要作用。尼罗罗非鱼（Oreochromis niloticus）在世界范围内广泛种植，市场需求强劲。它是鱼类免疫学研究的模型物种之一，其基因组目前已完全测序。该物种中免疫球蛋白 M 基因的存在及其在全身免疫中的主要作用已得到充分记录。迄今为止，尼罗罗非鱼的 IgT 基因尚未被鉴定，因此，没有关于这种免疫球蛋白同种型在罗非鱼免疫反应中的作用的信息。在目前的工作中，从罗非鱼头肾淋巴细胞中分离出新型分泌型和膜型免疫球蛋白 T 同种型以及 IgM 片段。通过定量 PCR 分析了它们在幼体发育过程中以及健康或受到脂多糖/迟缓爱德华氏菌攻击的罗非鱼成体的不同组织中的转录谱。在幼虫发育的早期阶段就检测到了 IgT 和 IgM 的存在。此外，这些基因在成年罗非鱼的基础条件下和E. tarda感染后表现出差异表达谱，这与这些免疫球蛋白在全身和粘膜区室中的效应子功能一致。我们的结果表明这种新的 Ig 可能参与罗非鱼的粘膜免疫。
Immunoglobulin molecules play an important role in the immune defense system in all jawed vertebrates, by protecting the organism from a wide variety of pathogens. Nile tilapia (Oreochromis niloticus) is extensively cultivated worldwide, with a strong established market demand. It constitutes one of the model species for the study of fish immunology and its genome is currently fully sequenced. The presence of the immunoglobulin M gene in this species is well documented, as well as its major role in systemic immunity. To date, the IgT gene from O. niloticus has not been identified and, therefore, no information is available on the role of this immunoglobulin isotype in the immune response in tilapia. In the present work, novel secreted and membrane immunoglobulin T isotypes and a fragment of IgM were isolated from tilapia head kidney lymphocytes. Their transcriptional profiles were analyzed by quantitative PCR in larval development and in different tissues of healthy or lipopolysaccharide/Edwardsiella tarda-challenged tilapia adults. The presence of IgT and IgM were detected in early stages of larval development. Additionally, these genes exhibited differential expression profiles in basal conditions and after E. tarda infection in adult tilapia, in accord with the proposed effector functions of these immunoglobulins in the systemic and mucosal compartments. Our results suggest the potential involvement of this new Ig in mucosal immunity in tilapia.