Abstract
Baylisascaris schroederi, a roundworm parasite of giant pandas, badly affects the health of its hosts. Diagnosis of this disease currently depends mainly on sedimentation floatation and Polymerase Chain Reaction (PCR) methods to detect the eggs. However, neither of these methods is suitable for diagnosis of early-stage panda baylisascariasis and no information on early diagnosis of this disease is available so far. Therefore, to develop an effective serologic diagnostic method, this study produced recombinant glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and thioredoxin peroxidase (Tpx) proteins from B. schroederi using a prokaryotic expression system. We determined the immunological characteristics of these proteins and their location in the parasite. Indirect enzyme-linked immunosorbent assays (ELISAs) were established to detect B. schroederi infection in giant pandas based on GAPDH and Tpx respectively. The open reading frame of the GAPDH gene (1083 bp) encoded a 39 kDa protein, while the predicted molecular weight of Tpx (588 bp) was 21.6 kDa. Western-blotting analysis revealed that both recombinant proteins could be recognized with positive serum of pandas infected with B. schroederi. Immunohistochemical staining showed that the endogenous GAPDH of B. schroederi was widely distributed in the worm while Tpx was mainly localized in the muscle, eggs, gut wall, uterus wall and hypodermis. Serological tests showed that the GAPDH-based indirect ELISA had a sensitivity of 95.83% and specificity of 100%, while the test using Tpx as the antigen had sensitivity of 75% and specificity of 91.7%. Thus, B. schroederi Tpx is unsuitable as a diagnostic antigen for baylisascariasis, but B. schroederi GAPDH is a good candidate diagnostic antigen for B. schroederi in pandas.
Highlights
The giant panda (Ailuropoda melanoleuca) is well known as a conservation flagship species and a “living fossil”
Several thioredoxin peroxidase (Tpx)-based enzyme-linked immunosorbent assay (ELISA) methods have been developed and the results demonstrate that Tpx is a candidate diagnostic antigen for some parasitic diseases [15,16,17]
The existing existing diagnostic diagnostic methods methods for for panda panda baylisascariasis, baylisascariasis, including including sedimentation sedimentation floatation floatation and Polymerase Chain Reaction (PCR) detection, detection,are arebased basedonondetecting detecting eggs separated from feces
Summary
The giant panda (Ailuropoda melanoleuca) is well known as a conservation flagship species and a “living fossil”. Baylisascaris schroederi is a common roundworm parasite of the intestine of giant pandas [1]. Genes 2017, 8, 293 positive rate of B. schroederi eggs in captive panda feces is about 25.71% [4] Hosts infected with this worm may have clinical symptoms such as malnutrition, fasting, emesis, diarrhea, emaciation, cough, cachexia among others [5]. A large quantity of parasites may cause intestinal obstruction of giant pandas, and even death [6,7]. The diagnosis of this disease mainly depends on sedimentation floatation and Polymerase
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
