Agius C, Roberts R J
Department of Biological Sciences, University of Malta, Malta.
J Fish Dis. 2003 Sep;26(9):499-509. doi: 10.1046/j.1365-2761.2003.00485.x.
Melano-macrophage centres, also known as macrophage aggregates, are distinctive groupings of pigment-containing cells within the tissues of heterothermic vertebrates. In fish they are normally located in the stroma of the haemopoietic tissue of the spleen and the kidney, although in amphibians and reptiles, and some fish, they are also found in the liver. They may also develop in association with chronic inflammatory lesions elsewhere in the body and during ovarian atresia. In higher teleosts, they often exist as complex discrete centres, containing lymphocytes and macrophages, and may be primitive analogues of the germinal centres of lymph nodes. Melano-macrophage centres usually contain a variety of pigments, including melanins, and these increase in range and volume in older fish or in the presence of cachectic disease. Melano-macrophage centres act as focal depositories for resistant intracellular bacteria, from which chronic infections may develop. Iron capture and storage in haemolytic diseases appears to be a primary function, but antigen trapping and presentation to lymphocytes, sequestration of products of cellular degradation and potentially toxic tissue materials, such as melanins, free radicals and catabolic breakdown products are among other functions that have been ascribed. Recent work suggests that they are a site of primary melanogenesis rather than mere storage. Melano-macrophage centres increase in size or frequency in conditions of environmental stress and have been suggested as reliable biomarkers for water quality in terms of both deoxygenation and iatragenic chemical pollution.
黑素巨噬细胞中心，也被称为巨噬细胞聚集体，是变温脊椎动物组织内含有色素细胞的独特聚集。在鱼类中，它们通常位于脾脏和肾脏造血组织的基质中，不过在两栖动物、爬行动物以及一些鱼类中，也能在肝脏中发现它们。它们也可能与身体其他部位的慢性炎症病变以及卵巢闭锁过程有关而形成。在高等硬骨鱼中，它们常以复杂的离散中心形式存在，包含淋巴细胞和巨噬细胞，可能是淋巴结生发中心的原始类似物。黑素巨噬细胞中心通常含有多种色素，包括黑色素，在老龄鱼或患有恶病质疾病时，这些色素的种类和数量会增加。黑素巨噬细胞中心充当抗性细胞内细菌的局部储存库，慢性感染可能由此发展而来。在溶血性疾病中捕获和储存铁似乎是其主要功能，但抗原捕获并呈递给淋巴细胞、隔离细胞降解产物以及潜在有毒组织物质（如黑色素、自由基和分解代谢产物）等也是其被赋予的其他功能。最近的研究表明，它们是原发性黑色素生成的场所而非仅仅是储存场所。在环境压力条件下，黑素巨噬细胞中心的大小或频率会增加，并且在脱氧和医源性化学污染方面，它们已被认为是水质的可靠生物标志物。
