Prokaryotic Expression and Serodiagnostic Potential of Glyceraldehyde-3-Phosphate Dehydrogenase and
Thioredoxin Peroxidase fromBaylisascarisschroederi
Yu Li, Ying Sun, Xiaobin Gu, Yue Xie, Weiming Lai, Bo Jing,
Xuerong Peng andGuangyou Yang
Abstract
Baylisascaris schroederi, a roundworm parasite of giant pandas, badly affects the health of itshosts. Diagnosis of this disease currently depends mainly on sedimentation floatation and PolymeraseChain Reaction (PCR) methods to detect the eggs. However, neither of these methods is suitablefor diagnosis of early-stage panda baylisascariasis and no information on early diagnosis of thisdisease is available so far. Therefore, to develop an effective serologic diagnostic method, this studyproduced recombinant glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and thioredoxinperoxidase (Tpx) proteins fromB. schroederiusing a prokaryotic expression system. We determinedthe immunological characteristics of these proteins and their location in the parasite. Indirectenzyme-linked immunosorbent assays (ELISAs) were established to detectB. schroederiinfectionin giant pandas based on GAPDH and Tpx respectively. The open reading frame of theGAPDH gene (1083 bp) encoded a 39 kDa protein, while the predicted molecular weight of Tpx (588 bp) was21.6 kDa. Western-blotting analysis revealed that both recombinant proteins could be recognizedwith positive serum of pandas infected withB. schroederi. Immunohistochemical staining showedthat the endogenous GAPDH ofB. schroederiwas widely distributed in the worm while Tpx wasmainly localized in the muscle, eggs, gut wall, uterus wall and hypodermis. Serological tests showedthat the GAPDH-based indirect ELISA had a sensitivity of 95.83% and specificity of 100%, while thetest using Tpx as the antigen had sensitivity of 75% and specificity of 91.7%. Thus,B. schroederiTpx isunsuitable as a diagnostic antigen for baylisascariasis, butB. schroederiGAPDH is a good candidatediagnostic antigen forB. schroederiin pandas.
copyright:© The Author(s)2017.
Genes2017,8(11), 293. doi:10.3390/genes8110293
Read Full Text:http://www.mdpi.com/2073-4425/8/11/293
