Nyholm S V, McFall-Ngai M J
Pacific Biomedical Research Center, University of Hawaii, Honolulu, 96813, USA.
Biol Bull. 1998 Oct;195(2):89-97. doi: 10.2307/1542815.
The symbiosis between the squid Euprymna scolopes and the luminous bacterium Vibrio fischeri has a pronounced diel rhythm, one component of which is the venting of the contents of the light organ into the surrounding seawater each day at dawn. In this study, we explored the use of this behavior to sample the microenvironment of the light-organ crypts. Intact crypt contents, which emerge from the lateral pores of the organ as a thick paste-like exudate, were collected from anesthetized host animals that had been exposed to a light cue. Microscopy revealed that the expelled material is composed of a conspicuous population of host cells in association with the bacterial symbionts, all of which are embedded in a dense acellular matrix that strongly resembles the bacteria-based biofilms described in other systems. Assays of the viability of expelled crypt cells revealed no dead bacterial symbionts and a mixture of live and dead host cells. Analyses of the ultrastructure, biochemistry, and phagocytic activity of a subset of the host cell population suggested that some of these cells are macrophage-like molluscan hemocytes.
乌贼（Euprymna scolopes）与发光细菌费氏弧菌（Vibrio fischeri）之间的共生关系具有明显的昼夜节律，其中一个组成部分是每天黎明时发光器官的内容物排入周围海水中。在本研究中，我们探索了利用这种行为对发光器官隐窝的微环境进行采样。从暴露于光信号的麻醉宿主动物中收集完整的隐窝内容物，这些内容物从器官的侧孔中以浓稠的糊状渗出物形式出现。显微镜检查显示，排出的物质由大量与细菌共生体相关的宿主细胞组成，所有这些细胞都嵌入在一种致密的无细胞基质中，该基质与其他系统中描述的基于细菌的生物膜非常相似。对排出的隐窝细胞活力的检测显示没有死亡的细菌共生体，以及活的和死的宿主细胞的混合物。对一部分宿主细胞群体的超微结构、生物化学和吞噬活性的分析表明，其中一些细胞是类似巨噬细胞的软体动物血细胞。
