PDF(Pubmed)
Abstract：
Marine fish larvae often experience high mortality unrelated to predation during early life stages, and farmed ballan wrasse (Labrus bergylta) is no exception. Knowing when the adaptive immune system is developed and fully functional, and how nutrition may modulate these processes is therefore of importance to establish effective prophylactic measures and will also extend the relatively limited knowledge on the immune system in lower vertebrates. The thymus anlage of ballan wrasse was found to be histologically visible for the first time at larval stage 3 (20-30 days post hatch, dph) and becomes lymphoid at stage 5 (50-60 dph) correlating with an increase of T-cell marker transcripts. At this stage, a clear zonation into a RAG1+ cortex and a RAG1- CD3ϵ+ medulla was distinguished, indicating that T-cell maturation processes in ballan wrasse are similar to other teleosts. The higher abundance of CD4-1+ compared to CD8β+ cells in the thymus together with the apparent lack of CD8β+ cells in gill, gut, and pharynx, where CD4-1+ cells were identified, indicates that helper T-cells have a more prominent role during larval development compared to cytotoxic T-cells. As ballan wrasse lacks a stomach but has an exceptionally high IgM expression in the hindgut, we hypothesize that helper T-cells are crucial for activation and recruitment of IgM+ B-cells and possibly other leukocytes to the gut during early development. Nutritional factors such as DHA/EPA, Zn and Se may lead to an earlier expression of certain T-cell markers as well as a larger size of the thymus, indicating an earlier onset of adaptive immunity. Including live feeds that supplies the larva with higher amounts of these nutrients can therefore be beneficial for ballan wrasse farming.
摘要：
海洋鱼类幼虫通常在生命早期阶段经历与捕食无关的高死亡率，养殖巴兰·拉塞（Labrusbergylta）也不例外。知道适应性免疫系统何时发展并充分发挥作用，因此，营养如何调节这些过程对于建立有效的预防措施很重要，并且还将扩展有关低等脊椎动物免疫系统的相对有限的知识。在幼虫阶段3（孵化后20-30天，dph），并在第5阶段（50-60dph）变为淋巴样，与T细胞标记物转录本的增加有关。在这个阶段,区分为RAG1皮质和RAG1-CD3ε髓质的清晰分区，表明巴兰鱼的T细胞成熟过程与其他硬骨鱼相似。胸腺中CD4-1+的丰度高于CD8β+的细胞，并且在g中明显缺乏CD8β+的细胞，gut,gut和咽部,其中CD4-1+细胞被鉴定，表明与细胞毒性T细胞相比，辅助T细胞在幼虫发育过程中具有更突出的作用。由于BallanWrasse缺乏胃，但在后肠中具有异常高的IgM表达，我们假设辅助性T细胞在早期发育过程中对于IgM+B细胞和可能的其他白细胞的激活和募集至肠道至关重要.营养因素如DHA/EPA，Zn和Se可能导致某些T细胞标志物的较早表达以及胸腺的较大大小，表明适应性免疫较早开始。因此，包括为幼虫提供较高量的这些营养素的活饲料可以有益于巴兰鱼养殖。
