The function of a tissue is determined by its construction and cellular composition. The action of different genes can thus only be understood properly when seen in the context of the environment in which they are expressed and function. We now experience a renaissance in morphological research in fish, not only because, surprisingly enough, large structures have remained un-described until recently, but also because improved methods for studying morphological characteristics in combination with expression analysis are at hand. In this review, we address anatomical features of teleost immune tissues. There are approximately 30,000 known teleost fish species and only a minor portion of them have been studied. We aim our review at the Atlantic salmon (Salmo salar) and other salmonids, but when applicable, we also present information from other species. Our focus is the anatomy of the kidney, thymus, spleen, the interbranchial lymphoid tissue (ILT), the newly discovered salmonid cloacal bursa and the naso-pharynx associated lymphoid tissue (NALT).

组织的功能由其结构和细胞组成决定。因此，只有在它们表达和发挥功能的环境中才能正确理解不同基因的作​​用。我们现在经历了鱼类形态学研究的复兴，这不仅是因为令人惊讶的是，大型结构直到最近才被描述，而且还因为结合表达分析来研究形态特征的改进方法已经出现。在这篇综述中，我们讨论了硬骨鱼免疫组织的解剖特征。大约有 30,000 种已知的硬骨鱼类，其中只有一小部分被研究过。我们的审查目标是大西洋鲑鱼 ( Salmo salar) 和其他鲑鱼，但在适用的情况下，我们也会提供其他物种的信息。我们的重点是肾脏、胸腺、脾脏、分支间淋巴组织 (ILT)、新发现的鲑鱼泄殖腔囊和鼻咽相关淋巴组织 (NALT) 的解剖结构。