Macalanda Adrian Miki C, Angeles Jose Ma M, Moendeg Kharleezelle J, Dang Anh Tm, Higuchi Luna, Inoue Noboru, Xuan Xuenan, Kirinoki Masashi, Chigusa Yuichi, Leonardo Lydia R, Villacorte Elena A, Rivera Pilarita T, Goto Yasuyuki, Kawazu Shin-Ichiro
National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Hokkaido 080-8555, Japan.
Department of Tropical Medicine and Parasitology, Dokkyo Medical University, Mibu, Tochigi 321-0293, Japan.
J Vet Med Sci. 2018 Feb 2;80(1):156-163. doi: 10.1292/jvms.17-0579. Epub 2017 Nov 28.
Asian schistosomiasis caused by Schistosoma japonicum is a serious zoonotic disease endemic in China, the Philippines and parts of Indonesia. Mass drug administration in endemic areas resulted to decline in disease severity and intensity. The low intensity of infection limits the use of current parasitological methods for schistosomiasis diagnosis. Detection of parasite circulating antigens might provide more informative result as it may indicate the true status of infection. In this study, S. japonicum thioredoxin peroxidase-1 (SjTPx-1) a 22 kDa secreted antioxidant enzyme expressed throughout the life stages of the parasite was evaluated for its potential use as a biomarker for schistosomiasis japonica infection. Rabbit polyclonal antibody and mouse monoclonal antibodies (mAbs) were raised against the recombinant SjTPx-1 (rSjTPx-1). The antibodies produced against the recombinant antigen was confirmed to detect the native SjTPx-1 in crude adult worm lysate. Likewise, the specific binding of mAbs to parasite TPx-1 and not to mammalian peroxiredoxin-1 orthologues was also confirmed. The double antibody sandwich ELISA developed in this study was able to detect at least 1 ng/ml of rSjTPx-1. In addition, this method was able to detect the antigen from all serum samples of experimentally infected rabbit and mice. The diagnostic potential of SjTPx-1 in human clinical samples was also evaluated, in which 4 out of 10 stool-confirmed serum samples had detectable levels of the antigen. The results suggest that SjTPx-1 can be a potential biomarker for Asian zoonotic schistosomiasis.
由日本血吸虫引起的亚洲血吸虫病是一种严重的人畜共患病，在中国、菲律宾和印度尼西亚的部分地区流行。在流行地区进行大规模药物治疗导致疾病严重程度和感染强度下降。低感染强度限制了目前用于血吸虫病诊断的寄生虫学方法的使用。检测寄生虫循环抗原可能会提供更有价值的结果，因为它可能表明感染的真实状况。在本研究中，对日本血吸虫硫氧还蛋白过氧化物酶-1（SjTPx-1）进行了评估，它是一种22 kDa的分泌型抗氧化酶，在寄生虫的整个生命周期中都有表达，评估其作为日本血吸虫感染生物标志物的潜在用途。制备了针对重组SjTPx-1（rSjTPx-1）的兔多克隆抗体和小鼠单克隆抗体（mAbs）。证实针对重组抗原产生的抗体能检测成虫粗裂解物中的天然SjTPx-1。同样，也证实了单克隆抗体与寄生虫TPx-1的特异性结合，而不与哺乳动物过氧化物还原酶-1直系同源物结合。本研究开发的双抗体夹心ELISA能够检测至少1 ng/ml的rSjTPx-1。此外，该方法能够检测实验感染兔和小鼠的所有血清样本中的抗原。还评估了SjTPx-1在人类临床样本中的诊断潜力，在10份粪便确诊的血清样本中，有4份检测到了可检测水平的抗原。结果表明，SjTPx-1可能是亚洲人畜共患血吸虫病的潜在生物标志物。
