Mebius Mirjam M, Op Heij Jody M J, Tielens Aloysius G M, de Groot Philip G, Urbanus Rolf T, van Hellemond Jaap J
Department of Medical Microbiology and Infectious Diseases, Erasmus University Medical Center, Rotterdam, The Netherlands; Department of Clinical Chemistry and Haematology, University Medical Center Utrecht, Utrecht, The Netherlands.
Department of Clinical Chemistry and Haematology, University Medical Center Utrecht, Utrecht, The Netherlands.
Mol Biochem Parasitol. 2018 Apr;221:10-13. doi: 10.1016/j.molbiopara.2018.02.001. Epub 2018 Feb 4.
Cathepsin peptidases form a major component of the secreted proteins of the blood-feeding trematodes Fasciola hepatica and Schistosoma mansoni. These peptidases fulfill many functions, from facilitating infection to feeding and immune evasion. In this study, we examined the Fasciola cathepsin L peptidases FhCL1, FhCL2, and FhCL3 and the schistosomal cathepsin peptidases SmCB1 and SmCL3 for their anticoagulant properties. Although no direct anticoagulant effect of these peptidases was observed, we discovered that cathepsin peptidases from Fasciola, but not from Schistosoma, were able to degrade purified fibrinogen, with FhCL1 having the highest fibrinogenolytic activity. Additionally, FhCL1 and FhCL2 both efficiently degraded fibrin. The lack of a direct anticoagulant or fibrinolytic effect of these peptidases is explained by their inhibition by plasma components. However, within the parasite gut, high concentrations of these peptidases could induce an anticoagulant environment, facilitating blood-feeding for extended periods.
组织蛋白酶肽酶是吸血吸虫肝片吸虫和曼氏血吸虫分泌蛋白的主要组成部分。这些肽酶具有多种功能，从促进感染到进食和免疫逃避。在本研究中，我们检测了肝片吸虫组织蛋白酶L肽酶FhCL1、FhCL2和FhCL3以及血吸虫组织蛋白酶肽酶SmCB1和SmCL3的抗凝特性。尽管未观察到这些肽酶有直接的抗凝作用，但我们发现来自肝片吸虫而非血吸虫的组织蛋白酶肽酶能够降解纯化的纤维蛋白原，其中FhCL1具有最高的纤维蛋白原分解活性。此外，FhCL1和FhCL2均能有效降解纤维蛋白。这些肽酶缺乏直接的抗凝或纤维蛋白溶解作用是由于它们受到血浆成分的抑制。然而，在寄生虫肠道内，高浓度的这些肽酶可诱导形成抗凝环境，有利于长时间进食血液。
