Ryan Institute, National University of Ireland Galway, Ireland.
Mol Immunol. 2011 Sep;48(15-16):2102-12. doi: 10.1016/j.molimm.2011.07.003. Epub 2011 Jul 30.
The aim of the present work was to investigate the transcriptome response of gilthead sea bream (Sparus aurata) after challenge with the myxosporean Enteromyxum leei, a wide-spread enteric parasite causing heavy economic losses in Mediterranean sparid farms. This parasite causes severe desquamative enteritis which usually leads to death of the fish, and there are no preventative or curative treatments for this enteromyxosis. After 113 days of exposure to parasite-contaminated effluent, fish were classified into three cohorts: control fish not exposed to parasite, those that were exposed and infected, and those that were exposed but not infected. In order to detect target genes that may be candidates for infective status or resistance, a cDNA microarray containing 18,490 cDNA clones enriched in genes differentially expressed after infection was hybridised with head kidney and intestine samples. In infected fish, 371 and 373 genes were differentially regulated at the >1.5-fold level in intestine and head kidney respectively, whereas in non-infected fish 175 and 501 genes were differentially regulated in these tissues, respectively. A global marked gene down-regulation was evident in infected fish, mainly in genes involved in the immune and acute phase response particularly complement and mannose binding lectin. Microarray analysis demonstrated a complex interplay between host and/or parasite derived proteases and protease inhibitors, apoptosis, cell proliferation and antioxidant defence genes in exposed fish. In the head kidney of non-infected fish a marked depression of genes involved in the acute phase response was evident. By contrast, in the intestine of non-infected fish, interferon-stimulated and MHC class II genes involved in antigen processing and presentation were up-regulated, possibly indicating that an active immune response at the local level is important to avoid infection with or proliferation of the parasite.
本研究旨在探究真鲷（Sparus aurata）在感染粘孢子虫（Enteromyxum leei）后的转录组应答，该粘孢子虫是一种广泛分布的肠道寄生虫，会给地中海鲷鱼养殖场造成严重的经济损失。这种寄生虫会导致严重的脱屑性肠炎，通常会导致鱼类死亡，目前尚无针对这种粘孢子虫病的预防或治疗方法。在接触受寄生虫污染的污水 113 天后，将鱼分为三组：未接触寄生虫的对照组、接触寄生虫并感染的感染组、接触寄生虫但未感染的未感染组。为了检测可能成为感染状态或抗性候选的靶基因，使用含有 18490 个 cDNA 克隆的 cDNA 微阵列进行杂交，这些克隆在感染后差异表达的基因中富集。在感染组的鱼中，肠道和头肾中分别有 371 个和 373 个基因的表达水平差异超过 1.5 倍，而非感染组的鱼中分别有 175 个和 501 个基因的表达水平差异超过 1.5 倍。感染组的鱼中明显出现了基因下调的情况，主要是与免疫和急性期反应相关的基因，特别是补体和甘露糖结合凝集素相关的基因。微阵列分析表明，在暴露的鱼中，宿主和/或寄生虫来源的蛋白酶和蛋白酶抑制剂、细胞凋亡、细胞增殖和抗氧化防御基因之间存在复杂的相互作用。在未感染的鱼的头肾中，急性期反应相关基因的表达明显下调。相比之下，在未感染的鱼的肠道中，干扰素刺激和 MHC Ⅱ类基因的表达上调，这些基因参与抗原加工和呈递，这可能表明局部水平的主动免疫反应对于避免寄生虫感染或增殖很重要。
