Constitutive differences in Cu/Zn superoxide dismutase mRNA levels and activity in hernocytes of Biomphalaria glabrata (Mollusca) that are either susceptible or resistant to Schistosoma mansoni (Trematoda)
Constitutive differences in Cu/Zn superoxide dismutase mRNA levels and activity in hernocytes of Biomphalaria glabrata (Mollusca) that are either susceptible or resistant to Schistosoma mansoni (Trematoda)
复制标题
DOI：
10.1016/j.molbiopara.2004.06.011
复制
发表时间：
2004-10-01
影响因子：
1.5
通讯作者：
Bayne, CJ
中科院分区：
文献类型：
--
作者：
Goodall, CP;Bender, RC;Bayne, CJ
光滑双脐蜗牛的遗传品系对曼氏血吸虫的抵抗力各不相同。光滑拟杆菌血淋巴中循环的吞噬细胞（血细胞）在蜗牛的先天免疫反应中发挥着重要作用。抗性光滑拟杆菌的血细胞在体外通过涉及呼吸爆发的机制杀死曼氏链球菌。活性氧（ROS）是呼吸爆发的产物，可以充当氧化损伤和免疫相关细胞内信号通路的介质。一种特定的 ROS，过氧化氢 (H2O2)，已被证明参与血细胞介导的孢子被杀伤。我们测试了这样的假设：铜/锌超氧化物歧化酶 (SOD) 是一种催化超氧阴离子转化为 H2O2 的胞质酶，在抗性和易感性蜗牛品系之间存在某种差异。我们报告了具有典型胞质 Cu/Zn SOD 的所有特征的血细胞转录本（GenBank 登录号 AY505496 和 AY505497）。抗性蜗牛血细胞中 Cu/Zn SOD mRNA 的量是易感蜗牛血细胞的两倍，这与抗性血细胞中 Cu/Zn SOD 酶活性的增加直接相关。其他实验确定，孢子囊的体外相互作用/封装不会影响任一蜗牛品系血细胞中的 Cu/Zn SOD mRNA 水平。因此，这种宿主-寄生虫系统中的抗性似乎并不依赖于血细胞 Cu/Zn SOD 的转录反应，但可能至少部分归因于 Cu/Zn SOD 酶促水平的组成性升高。 (C) 2004 Elsevier B.V. 保留所有权利。
Genetic strains of the snail Biomphalaria glabrata vary in their resistance to the parasite Schistosoma mansoni. Phagocytic cells (hemocytes) circulating in the hemolymph of B. glabrata play an essential role in the snail's innate immune response. Hemocytes of resistant B. glabrata kill S. mansoni in vitro via a mechanism which involves a respiratory burst. Reactive oxygen species (ROS), which are products of the respiratory burst, can act as mediators of both oxidative damage and of immune-related intracellular signaling pathways. One specific ROS, hydrogen peroxide (H2O2), has been shown to be involved in hemocyte-mediated sporocyst killing. We tested the hypothesis that Cu/Zn superoxide dismutase (SOD), a cytosolic enzyme that catalyzes the conversion of superoxide anion to H2O2, is somehow different between resistant and susceptible snail strains. We report a hemocyte transcript with all the features of a typical cytosolic Cu/Zn SOD (GenBank accession numbers AY505496 and AY505497). The amount of Cu/Zn SOD mRNA in hemocytes from resistant snails was double that of hemocytes from susceptible snails, and this correlated directly with an increased Cu/Zn SOD enzymatic activity in resistant hemocytes. Additional experiments determined that in vitro interaction/encapsulation of sporocysts did not influence Cu/Zn SOD mRNA levels in hemocytes from either snail strain. Thus, resistance in this host-parasite system does not appear to depend on a transcriptional response of hemocyte Cu/Zn SOD, but may be due, at least in part, to a constitutively elevated enzymatic level of Cu/Zn SOD. (C) 2004 Elsevier B.V. All rights reserved.