Department of Pathobiology, Faculty of Science, Mahidol University, Rama VI Rd, Ratchathewi, Bangkok, 10400, Thailand.
Parasitol Res. 2013 Oct;112(10):3653-9. doi: 10.1007/s00436-013-3553-6. Epub 2013 Aug 7.
Leucine aminopeptidase (LAP) is expressed in all stages of Fasciola gigantica and, hence, is considered as a potential vaccine candidate. In this study, we have tested a vaccine potential of LAP and the types of immune responses it elicited in vaccinated mice. Recombinant F. gigantica leucine aminopeptidase (rFgLAP) was expressed in Escherichia coli, BL21 (DE3). The imprinting control region mice subcutaneously immunized with 50 μg of rFgLAP combined with Freund's adjuvant (n = 10) exhibited a significant reduction in worm recoveries when compared with non-immunized and Freund's adjuvant controls at 60.8 and 64.3%, respectively, and both T helper (Th)1 and Th2 humoral immune responses were elicited in the hosts as reflected by the levels of IgG1 and IgG2a, with Th2 predominating. The levels of IgG1- and IgG2a-specific antibodies to rFgLAP were inversely and significantly correlated with the numbers of worm recoveries. The rFgLAP-vaccinated mice showed significantly reduced levels of serum glutamic oxaloacetic transaminase and serum glutamic pyruvic transaminase and liver damage. These indicated that rFgLAP has a potential as a vaccine candidate against F. gigantica, whose efficacy will be studied further in economic animals including cattle, sheep, and goat.
亮氨酸氨基肽酶（LAP）在肝片吸虫的所有发育阶段均有表达，因此被认为是一种潜在的疫苗候选物。在这项研究中，我们测试了 LAP 的疫苗潜力及其在接种疫苗的小鼠中引发的免疫反应类型。重组 F. gigantica 亮氨酸氨基肽酶（rFgLAP）在大肠杆菌 BL21（DE3）中表达。用 50 μg rFgLAP 与弗氏佐剂皮下免疫印记控制区小鼠（n = 10），与未免疫和弗氏佐剂对照组相比，在第 60.8 和 64.3%时分别显著降低了蠕虫回收率，并且在宿主中均引发了辅助性 T 细胞（Th）1 和 Th2 体液免疫反应，反映在 IgG1 和 IgG2a 的水平上，以 Th2 为主。rFgLAP 特异性 IgG1 和 IgG2a 抗体的水平与蠕虫回收率呈负相关且具有统计学意义。rFgLAP 疫苗接种的小鼠的血清谷氨酸草酰乙酸转氨酶和血清谷氨酸丙酮酸转氨酶水平以及肝损伤显著降低。这表明 rFgLAP 具有作为肝片吸虫疫苗候选物的潜力，其在包括牛、绵羊和山羊在内的经济动物中的功效将进一步研究。
