Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Institute for Infectiology, Insel Riems, Germany; Laboratory of Fish Pathology, Department of Veterinary Medicine, Nihon University, Fujisawa, Kanagawa, Japan.
Faculty of Fisheries, Kagoshima University, Shimoarata, Kagoshima 890-0056, Japan.
Fish Shellfish Immunol. 2014 Jan;36(1):215-22. doi: 10.1016/j.fsi.2013.11.004. Epub 2013 Nov 12.
Eomesodermin (Eomes), a T-box transcription factor, is a key molecule associated with function and differentiation of CD8(+) T cells and NK cells. Previously, two teleost Eomes genes (Eomes-a and -b), which are located on different chromosomes, were identified and shown to be expressed in zebrafish lymphocytes. For the present study, we identified these genes in rainbow trout and ginbuna crucian carp. Deduced Eomes-a and -b amino acid sequences in both fish species contain a highly conserved T-box DNA binding domain. In RT-PCR, both Eomes transcripts were readily detectable in a variety of tissues in rainbow trout and ginbuna. The high expression of Eomes-a and -b in brain and ovary suggests involvement in neurogenesis and oogenesis, respectively, while their expression in lymphoid tissues presumably is associated with immune functions. Investigation of separated lymphocyte populations from pronephros indicated that both Eomes-a and -b transcripts were few or absent in IgM(+) lymphocytes, while relatively abundant in IgM(-)/CD8α(+) and IgM(-)/CD8α(-) populations. Moreover, we sorted trout CD8α(+) lymphocytes from mucosal and non-mucosal lymphoid tissues and compared the expression profiles of Eomes-a and -b with those of other T cell-related transcription factor genes (GATA-3, T-bet and Runx3), a Th1 cytokine gene (IFN-γ) and a Th2 cytokine gene (IL-4/13A). Interestingly, the tissue distribution of Eomes-a/b, T-bet, and Runx3 versus IFN-γ transcripts did not reveal simple correlations, suggesting tissue-specific properties of CD8α(+) lymphocytes and/or multiple modes that drive IFN-γ expressions.
Eomesodermin (Eomes)，一种 T 盒转录因子，是与 CD8(+) T 细胞和 NK 细胞的功能和分化相关的关键分子。先前，两种硬骨鱼 Eomes 基因（Eomes-a 和 -b）被鉴定出来，它们位于不同的染色体上，并在斑马鱼淋巴细胞中表达。在本研究中，我们在虹鳟鱼和金鳜鱼中鉴定了这些基因。两种鱼类的 Eomes-a 和 -b 推断的氨基酸序列都含有高度保守的 T 盒 DNA 结合域。在 RT-PCR 中，Eomes-a 和 -b 在虹鳟鱼和金鳜鱼的各种组织中都能轻易检测到。Eomes-a 和 -b 在大脑和卵巢中的高表达分别表明它们参与了神经发生和卵发生，而它们在淋巴组织中的表达可能与免疫功能有关。对来自前肾的分离淋巴细胞群体的研究表明，Eomes-a 和 -b 的转录物在 IgM(+) 淋巴细胞中很少或不存在，而在 IgM(-)/CD8α(+) 和 IgM(-)/CD8α(-)群体中相对丰富。此外，我们从黏膜和非黏膜淋巴组织中分选了虹鳟鱼 CD8α(+)淋巴细胞，并比较了 Eomes-a 和 -b 与其他 T 细胞相关转录因子基因（GATA-3、T-bet 和 Runx3）、Th1 细胞因子基因（IFN-γ）和 Th2 细胞因子基因（IL-4/13A）的表达谱。有趣的是，Eomes-a/b、T-bet 和 Runx3 与 IFN-γ 转录物的组织分布没有显示出简单的相关性，这表明 CD8α(+)淋巴细胞具有组织特异性特性和/或多种驱动 IFN-γ 表达的模式。
