Rauch Gisep, Kalbe Martin, Reusch Thorsten B H
Max-Planck-Institute for Limnology, Department of Evolutionary Ecology, 24306 Plön, Germany.
Biol Lett. 2006 Sep 22;2(3):382-4. doi: 10.1098/rsbl.2006.0462.
Red Queen models of host-parasite coevolution are based on genotype by genotype host-parasite interactions. Such interactions require a genotype specific host defence and, simultaneously, a genotype specific parasite infectivity. Specificity is defined here as defence or infection ability successful against only a subset of genotypes of the same species. A specific defence depends on detectable genotypic variation on the parasite side and on a host defence mechanism that differentiates between parasite genotypes. In vertebrates, the MHC-based adaptive immune system can provide such a defence mechanism, but it needs at least several days to get fully mounted. In contrast, the innate immune system is immediately ready. The trematode parasite species used here reaches the immunologically protected eye lens of its three-spined stickleback (Gasterosteus aculeatus) host within 24 h. Thus, it disappears too fast for the fully mounted MHC-based adaptive immune system. In a complete cross-infection experiment using five fish-families and five parasite-clones, we found for the first time fish-family by parasite-clone interactions in vertebrates, although the parasite was only exposed to the immune system for maximally one day. Such interactions require a fast genotype specific defence, suggesting the importance of other defence mechanisms than the too slow, fully mounted adaptive immune system in vertebrates.
宿主 - 寄生虫协同进化的红皇后模型基于基因型对基因型的宿主 - 寄生虫相互作用。这种相互作用需要基因型特异性的宿主防御，同时也需要基因型特异性的寄生虫感染力。这里的特异性被定义为仅对同一物种的一部分基因型具有成功防御或感染能力。特异性防御取决于寄生虫方面可检测到的基因型变异以及能够区分寄生虫基因型的宿主防御机制。在脊椎动物中，基于主要组织相容性复合体（MHC）的适应性免疫系统可以提供这样一种防御机制，但它至少需要几天时间才能完全启动。相比之下，先天免疫系统随时准备就绪。这里使用的吸虫寄生虫物种在24小时内就能到达其三刺鱼（Gasterosteus aculeatus）宿主的免疫保护眼晶状体。因此，对于完全启动的基于MHC的适应性免疫系统来说，它消失得太快了。在一项使用五个鱼类家族和五个寄生虫克隆的完整交叉感染实验中，我们首次在脊椎动物中发现了鱼类家族与寄生虫克隆之间的相互作用，尽管寄生虫仅在免疫系统中暴露了最多一天。这种相互作用需要快速的基因型特异性防御，这表明除了脊椎动物中启动速度过慢的完全启动的适应性免疫系统之外，其他防御机制也很重要。
