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Han LL, Lu QQ, Li YL, Zheng WW, Ren P, Liu RD, Cui J, Wang ZQ. Application of a recombinant novel trypsin from Trichinella spiralis for serodiagnosis of trichinellosis. Parasit Vectors 2024; 17:9. [PMID: 38178167 PMCID: PMC10768479 DOI: 10.1186/s13071-023-06067-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2023] [Accepted: 11/26/2023] [Indexed: 01/06/2024] Open
Abstract
BACKGROUND The excretory/secretory (ES) antigen of Trichinella spiralis muscle larvae (ML) is currently the most widely used diagnostic antigen to detect T. spiralis infection. However, this antigen has certain drawbacks, such as a complicated ES antigen preparation process and lower sensitivity during the early phase of infection. The aim of this study was to investigate the features of a novel T. spiralis trypsin (TsTryp) and evaluate its potential diagnostic value for trichinellosis. METHODS The TsTryp gene was cloned and recombinant TsTryp (rTsTryp) expressed. Western blotting and an enzyme-linked immunosorbent assay (ELISA) were performed to confirm the antigenicity of rTsTryp. The expression pattern and distribution signature of TsTryp at various life-cycle stages of T. spiralis were analyzed by quantitative PCR, western blotting and the immunofluorescence test. An ELISA with rTsTryp and ML ES antigens was used to detect immunoglobulins G and M (IgG, IgM) in serum samples of infected mice, swine and humans. The seropositive results were further confirmed by western blot with rTsTryp and ML ES antigens. RESULTS TsTryp expression was observed in diverse T. spiralis life-cycle phases, with particularly high expression in the early developmental phase (intestinal infectious larvae and adults), with distribution observed mainly at the nematode outer cuticle and stichosome. rTsTryp was identified by T. spiralis-infected mouse sera and anti-rTsTryp sera. Natural TsTryp protease was detected in somatic soluble and ES antigens of the nematode. In mice infected with 200 T. spiralis ML, serum-specific IgG was first detected by rTsTryp-ELISA at 8 days post-infection (dpi), reaching 100% positivity at 12 dpi, and first detected by ES-ELISA at 10 dpi, reaching 100% positivity at 14 dpi. Specific IgG was detected by rTsTryp 2 days earlier than by ES antigens. When specific IgG was determined in serum samples from trichinellosis patients, the sensitivity of rTsTryp-ELISA and ES antigens-ELISA was 98.1% (51/52 samples) and 94.2% (49/52 samples), respectively (P = 0.308), but the specificity of rTsTryp was significantly higher than that of ES antigens (98.7% vs. 95.4%; P = 0.030). Additionally, rTsTryp conferred a lower cross-reaction, with only three serum samples in total testing positive from 11 clonorchiasis, 20 cysticercosis and 24 echinococcosis patients (1 sample from each patient group). CONCLUSIONS TsTryp was shown to be an early and highly expressed antigen at intestinal T. spiralis stages, indicating that rTsTryp represents a valuable diagnostic antigen for the serodiagnosis of early Trichinella infection.
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Affiliation(s)
- Lu Lu Han
- Department of Parasitology, Medical College, Zhengzhou University, Zhengzhou, 450001, China
| | - Qi Qi Lu
- Department of Parasitology, Medical College, Zhengzhou University, Zhengzhou, 450001, China
| | - Yang Li Li
- Department of Parasitology, Medical College, Zhengzhou University, Zhengzhou, 450001, China
| | - Wen Wen Zheng
- Department of Parasitology, Medical College, Zhengzhou University, Zhengzhou, 450001, China
| | - Pian Ren
- Department of Parasitology, Medical College, Zhengzhou University, Zhengzhou, 450001, China
| | - Ruo Dan Liu
- Department of Parasitology, Medical College, Zhengzhou University, Zhengzhou, 450001, China
| | - Jing Cui
- Department of Parasitology, Medical College, Zhengzhou University, Zhengzhou, 450001, China.
| | - Zhong Quan Wang
- Department of Parasitology, Medical College, Zhengzhou University, Zhengzhou, 450001, China.
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Liu Y, Liu J, Wang N, You X, Yang Y, Ding J, Liu X, Liu M, Li C, Xu N. Quantitative label-free proteomic analysis of excretory-secretory proteins in different developmental stages of Trichinella spiralis. Vet Res 2024; 55:4. [PMID: 38172978 PMCID: PMC10763447 DOI: 10.1186/s13567-023-01258-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2023] [Accepted: 11/27/2023] [Indexed: 01/05/2024] Open
Abstract
Trichinella spiralis (T. spiralis) is a zoonotic parasitic nematode with a unique life cycle, as all developmental stages are contained within a single host. Excretory-secretory (ES) proteins are the main targets of the interactions between T. spiralis and the host at different stages of development and are essential for parasite survival. However, the ES protein profiles of T. spiralis at different developmental stages have not been characterized. The proteomes of ES proteins from different developmental stages, namely, muscle larvae (ML), intestinal infective larvae (IIL), preadult (PA) 6 h, PA 30 h, adult (Ad) 3 days post-infection (dpi) and Ad 6 dpi, were characterized via label-free mass spectrometry analysis in combination with bioinformatics. A total of 1217 proteins were identified from 9341 unique peptides in all developmental stages, 590 of which were quantified and differentially expressed. GO classification and KEGG pathway analysis revealed that these proteins were important for the growth of the larvae and involved in energy metabolism. Moreover, the heat shock cognate 71 kDa protein was the centre of protein interactions at different developmental stages. The results of this study provide comprehensive proteomic data on ES proteins and reveal that these ES proteins were differentially expressed at different developmental stages. Differential proteins are associated with parasite survival and the host immune response and may be potential early diagnostic antigen or antiparasitic vaccine candidates.
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Affiliation(s)
- Yadong Liu
- State Key Laboratory for Diagnosis and Treatment of Severe Zoonotic Infectious Diseases, Key Laboratory for Zoonosis Research of the Ministry of Education, Institute of Zoonosis, and College of Veterinary Medicine, Jilin University, Changchun, 130062, China
| | - Juncheng Liu
- College of Veterinary Medicine, Shandong Agricultural University, Tai'an, 271018, China
| | - Nan Wang
- Jilin Agricultural University, Changchun, 130062, China
| | - Xihuo You
- Beijing Agrichina Pharmaceutical Co., Ltd., Wangzhuang Industrial Park, Airport Road, Shahe, Changping District, Beijing, 102206, China
| | - Yaming Yang
- Yunnan Institute of Parasitic Diseases, 6 Xiyuan Road, Puer, Yunnan, China
| | - Jing Ding
- State Key Laboratory for Diagnosis and Treatment of Severe Zoonotic Infectious Diseases, Key Laboratory for Zoonosis Research of the Ministry of Education, Institute of Zoonosis, and College of Veterinary Medicine, Jilin University, Changchun, 130062, China
| | - Xiaolei Liu
- State Key Laboratory for Diagnosis and Treatment of Severe Zoonotic Infectious Diseases, Key Laboratory for Zoonosis Research of the Ministry of Education, Institute of Zoonosis, and College of Veterinary Medicine, Jilin University, Changchun, 130062, China
| | - Mingyuan Liu
- State Key Laboratory for Diagnosis and Treatment of Severe Zoonotic Infectious Diseases, Key Laboratory for Zoonosis Research of the Ministry of Education, Institute of Zoonosis, and College of Veterinary Medicine, Jilin University, Changchun, 130062, China
| | - Chen Li
- State Key Laboratory for Diagnosis and Treatment of Severe Zoonotic Infectious Diseases, Key Laboratory for Zoonosis Research of the Ministry of Education, Institute of Zoonosis, and College of Veterinary Medicine, Jilin University, Changchun, 130062, China.
| | - Ning Xu
- State Key Laboratory for Diagnosis and Treatment of Severe Zoonotic Infectious Diseases, Key Laboratory for Zoonosis Research of the Ministry of Education, Institute of Zoonosis, and College of Veterinary Medicine, Jilin University, Changchun, 130062, China.
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Lobanov VA, Konecsni KA, Purves RW, Scandrett WB. Performance of indirect enzyme-linked immunosorbent assay using Trichinella spiralis-derived Serpin as antigen for the detection of exposure to Trichinella spp. in swine. Vet Parasitol 2022; 309:109744. [PMID: 35777187 DOI: 10.1016/j.vetpar.2022.109744] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Revised: 05/30/2022] [Accepted: 06/07/2022] [Indexed: 11/18/2022]
Abstract
Indirect enzyme-linked immunosorbent assay (ELISA) utilizing excretory-secretory (E-S) antigens of Trichinella spiralis is currently the method of choice for testing pigs and wild boars for exposure to Trichinella spp. The E-S proteins are released by first-stage larvae (L1) of this parasitic nematode maintained in vitro. However, the production of these antigens is cumbersome and time-consuming. The process requires animals to be experimentally infected with the parasite as the source of L1. Antigen production using recombinant technology would be more time- and cost-effective. In this study, we produced a Serpin of T. spiralis as a recombinant protein secreted by the yeast Pichia pastoris. The diagnostic performance of indirect ELISA with purified Serpin antigen was compared to that of E-S ELISA. Both Serpin ELISA and E-S ELISA demonstrated 98 % diagnostic specificity in testing 1056 pigs from the Canadian Trichinella-free commercial herd. Twenty of 21 pigs with non-negative test results in E-S ELISA tested negative by the confirmatory Western blot (WB) assay. Therefore, the diagnostic specificity of combined E-S ELISA and WB was 99.9 %. Forty-five sera collected at or after six weeks from 34 pigs experimentally infected with various numbers of T. spiralis L1 produced positive results in both E-S and Serpin ELISA, resulting in 100 % diagnostic sensitivity. However, testing of sera serially collected from four pigs experimentally infected with various low doses of T. spiralis L1 demonstrated a delayed Serpin-specific antibody response compared to seroconversion detected by E-S ELISA in three animals. Moreover, Serpin ELISA demonstrated significantly lower sensitivity for detecting antibodies induced by experimental infections of pigs with T. britovi, T. nativa, Trichinella T6 and T. pseudospiralis, suggesting that it will not provide consistent detection of exposure to sylvatic Trichinella spp. The validation data support the application of Serpin ELISA in seroepidemiological surveys for detecting exposure to T. spiralis in swine.
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Affiliation(s)
- Vladislav A Lobanov
- Center for Food-borne and Animal Parasitology, Canadian Food Inspection Agency, Saskatoon, Saskatchewan, Canada.
| | - Kelly A Konecsni
- Center for Food-borne and Animal Parasitology, Canadian Food Inspection Agency, Saskatoon, Saskatchewan, Canada
| | - Randy W Purves
- Center for Veterinary Drug Residues, Canadian Food Inspection Agency, Saskatoon, Saskatchewan, Canada
| | - W Brad Scandrett
- Center for Food-borne and Animal Parasitology, Canadian Food Inspection Agency, Saskatoon, Saskatchewan, Canada
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Zhai CC, Liu XL, Bai X, Jia ZJ, Chen SH, Tian LG, Ai L, Tang B, Liu MY, Wu XP, Chen JX. Bioinformatic Prediction and Production of Four Recombinant Proteins from Different Developmental Stages of Trichinella spiralis and Testing of Their Diagnostic Sensitivity in Mice. IRANIAN JOURNAL OF PARASITOLOGY 2021; 16:122-135. [PMID: 33786054 PMCID: PMC7988681 DOI: 10.18502/ijpa.v16i1.5531] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Background: Trichinellosis is a serious food-borne parasitic zoonosis, thus finding high quality antigens is the key to serodiagnosis of trichinosis. This article reports the characterization and sensitivity of four recombinant proteins expressed by four genes (Wn10, Zh68, T668, and Wm5) from different developmental stages of Trichinella spiralis for the diagnosis of trichinellosis in mice. Methods: This study was conducted in Jilin University and National Institute of Parasitic Diseases of Chinese Center for Disease Control and Prevention in 2017–2018. The structures and functions of the proteins encoded by four genes were predicted by bioinformatics analysis. The four genes were cloned and expressed, and the recombinant proteins were purified. Anti-Trichinella IgM and IgG antibodies in the sera of mice infected with T. spiralis from 1-45 d post-infection (dpi) were evaluated by ELISA. Results: The optimal antigen epitopes of four proteins (P1, P2, P3, and P4) encoded by the four genes from T- and B-cells were predicted, and four purified recombinant proteins (r-P1, r-P2, r-P3, and r-P4) were successfully produced. For IgM, the antibody levels detected by the four recombinant antigens were approximately equal to the cut-off value. Anti-Trichinella IgG antibodies were first detected by r-P1 at 8 dpi, followed by r-P2, r-P3, and r-P4 at 10 dpi, 14 dpi, and 16 dpi, respectively, and the antibody levels remained high until 45 dpi. Conclusion: The recombinant antigens r-P1, r-P2, r-P3, and r-P4 could be antigens that react with antibodies, they showed high sensitivity in the detection of anti-Trichinella IgG antibodies in mice. Among these proteins, r-P1 may be a candidate antigen for the detection of anti-Trichinella IgG antibodies in the early infection phase and exhibited the best sensitivity among the antigens.
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Affiliation(s)
- Cheng-Cheng Zhai
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, WHO Collaborating Center for Tropical Diseases, Key Laboratory of Parasite and Vector Biology, National Health and Family Planning Commission, Shanghai 200025, China.,Editorial Department of Chinese Journal of Clinical Medicine, Department of Research, Zhongshan Hospital, Fudan University, Shanghai 200032, China
| | - Xiao-Lei Liu
- Key Laboratory for Zoonoses Research, Ministry of Education, Institute of Zoonoses, Jilin University, Changchun 130062, China
| | - Xue Bai
- Key Laboratory for Zoonoses Research, Ministry of Education, Institute of Zoonoses, Jilin University, Changchun 130062, China
| | - Ze-Jun Jia
- Editorial Department of Chinese Journal of Clinical Medicine, Department of Research, Zhongshan Hospital, Fudan University, Shanghai 200032, China
| | - Shao-Hong Chen
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, WHO Collaborating Center for Tropical Diseases, Key Laboratory of Parasite and Vector Biology, National Health and Family Planning Commission, Shanghai 200025, China
| | - Li-Guang Tian
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, WHO Collaborating Center for Tropical Diseases, Key Laboratory of Parasite and Vector Biology, National Health and Family Planning Commission, Shanghai 200025, China
| | - Lin Ai
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, WHO Collaborating Center for Tropical Diseases, Key Laboratory of Parasite and Vector Biology, National Health and Family Planning Commission, Shanghai 200025, China
| | - Bin Tang
- Key Laboratory for Zoonoses Research, Ministry of Education, Institute of Zoonoses, Jilin University, Changchun 130062, China
| | - Ming-Yuan Liu
- Key Laboratory for Zoonoses Research, Ministry of Education, Institute of Zoonoses, Jilin University, Changchun 130062, China
| | - Xiu-Ping Wu
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, WHO Collaborating Center for Tropical Diseases, Key Laboratory of Parasite and Vector Biology, National Health and Family Planning Commission, Shanghai 200025, China
| | - Jia-Xu Chen
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, WHO Collaborating Center for Tropical Diseases, Key Laboratory of Parasite and Vector Biology, National Health and Family Planning Commission, Shanghai 200025, China
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Liu Y, Liu X, Li Y, Xu N, Yang Y, Liu M, Zhou Y. Evaluation of a cystatin-like protein of Trichinella spiralis for serodiagnosis and identification of immunodominant epitopes using monoclonal antibodies. Vet Parasitol 2020; 297:109127. [PMID: 32439275 DOI: 10.1016/j.vetpar.2020.109127] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Revised: 04/28/2020] [Accepted: 04/29/2020] [Indexed: 12/31/2022]
Abstract
An antigenic cystatin-like protein (Ts-CLP) selected from cDNA library of intestinal infective larvae at 6 h post-infection, was expressed by prokaryotes in the form of a histidine-tagged protein (rTs-CLP). The fusion protein was purified by an on-column refolding procedure using Ni-NTA affinity chromatography. An indirect rTs-CLP ELISA was developed using 270 known negative serum samples from commercial swine maintained under non-special pathogen free conditions. Based on the distribution of the signal-to-positive (S/P) ratio, a cut-off value was set at 0.30. Using this cut-off value, rTs-CLP ELISA was evaluated using sera from swine experimentally infected with 1000 and 50,000 muscle larvae of Trichinella spiralis. Specific IgG antibodies were detectable by rTs-CLP ELISA as soon as 17 days post-infection (dpi), but the commercial ELISA kit based on excretory-secretory (ES) antigens did not permit detection before 21 dpi. Three monoclonal antibodies (McAbs) against Ts-CLP (designated 1H9, 6B5 and 7F8) were obtained by screening with both rTs-CLP ELISA and ES ELISA methods. Two dominant epitopes recognized by McAbs were determined by analysis with overlapping fusion peptides and synthetic peptides. One epitope 39 HEALFSSDLKQESGV 53 was recognized by 1H9 and 6B5, and the other epitope 178 REALFSSDSKEQSGV 192 was recognized by 7F8. The generation of McAbs against Ts-CLP and the characterization of the two dominant epitopes provide a foundation for the development of a specific early serodiagnostic strategy for T. spiralis infection.
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Affiliation(s)
- Yan Liu
- Key Laboratory of Zoonoses Research, Ministry of Education, Institute of Zoonoses, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Xiaolei Liu
- Key Laboratory of Zoonoses Research, Ministry of Education, Institute of Zoonoses, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Yansong Li
- Key Laboratory of Zoonoses Research, Ministry of Education, Institute of Zoonoses, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Ning Xu
- Key Laboratory of Zoonoses Research, Ministry of Education, Institute of Zoonoses, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Yuying Yang
- College of Animal Sciences, Yangtze University, Jingzhou, China
| | - Mingyuan Liu
- Key Laboratory of Zoonoses Research, Ministry of Education, Institute of Zoonoses, College of Veterinary Medicine, Jilin University, Changchun, China.
| | - Yu Zhou
- Key Laboratory of Zoonoses Research, Ministry of Education, Institute of Zoonoses, College of Veterinary Medicine, Jilin University, Changchun, China; College of Animal Sciences, Yangtze University, Jingzhou, China.
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Wang ZQ, Liu RD, Sun GG, Song YY, Jiang P, Zhang X, Cui J. Proteomic Analysis of Trichinella spiralis Adult Worm Excretory-Secretory Proteins Recognized by Sera of Patients with Early Trichinellosis. Front Microbiol 2017; 8:986. [PMID: 28620363 PMCID: PMC5449722 DOI: 10.3389/fmicb.2017.00986] [Citation(s) in RCA: 61] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Accepted: 05/16/2017] [Indexed: 11/28/2022] Open
Abstract
The most commonly used serodiagnostic antigens for trichinellosis are the excretory-secretory (ES) antigens from T. spiralis muscle larvae (ML), but the specific antibodies against the ML ES antigens are usually negative during early stage of Trichinella infection. The recent studies demonstrated that T. spiralis adult worm (AW) antigens were recognized by mouse or swine infection sera on Western blot as early as 7–15 days post-infection (dpi), the AW antigens might contain the early diagnostic markers for trichinellosis. The purpose of this study was to screen early diagnostic antigens in T. spiralis AW ES proteins recognized by sera of early patients with trichinellosis. T. spiralis AW were collected at 72 h post-infection (hpi), and their ES antigens were analyzed by SDS-PAGE and Western blot. Our results showed that 5 protein bands (55, 48–50, 45, 44, and 36 kDa) were recognized by sera of early patients with trichinellosis collected at 19 dpi, and were subjected to shotgun LC–MS/MS and bioinformatics analyses. A total of 185 proteins were identified from T. spiralis protein database, of which 116 (67.2%) proteins had molecular weights of 30∼60 kDa, and 125 (67.6%) proteins with pI 4–7. Bioinformatic analyses showed that the identified proteins have a wide diversity of biological functions (binding of nucleotides, proteins, ions, carbohydrates, and lipids; hydrolase, transferase, and oxidoreductase, etc.). Several enzymes (e.g., adult-specific DNase II, serine protease and serine protease inhibitor) could be the invasion-related proteins and early diagnostic markers for trichinellosis. Moreover, recombinant T. spiralis serine protease (rTsSP-ZH68) was expressed in E. coli and its antigenicity was analyzed by Western blot with the early infection sera. The rTsSP-ZH68 was recognized by sera of infected mice at 8–10 dpi and sera of early patients with trichinellosis at 19 dpi. T. spiralis AW proteins identified in this study, especially serine protease, are the promising early diagnostic antigens and vaccine candidates for trichinellosis.
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Affiliation(s)
- Zhong Q Wang
- Department of Parasitology, Medical College, Zhengzhou UniversityZhengzhou, China
| | - Ruo D Liu
- Department of Parasitology, Medical College, Zhengzhou UniversityZhengzhou, China
| | - Ge G Sun
- Department of Parasitology, Medical College, Zhengzhou UniversityZhengzhou, China
| | - Yan Y Song
- Department of Parasitology, Medical College, Zhengzhou UniversityZhengzhou, China
| | - Peng Jiang
- Department of Parasitology, Medical College, Zhengzhou UniversityZhengzhou, China
| | - Xi Zhang
- Department of Parasitology, Medical College, Zhengzhou UniversityZhengzhou, China
| | - Jing Cui
- Department of Parasitology, Medical College, Zhengzhou UniversityZhengzhou, China
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Wang ZQ, Shi YL, Liu RD, Jiang P, Guan YY, Chen YD, Cui J. New insights on serodiagnosis of trichinellosis during window period: early diagnostic antigens from Trichinella spiralis intestinal worms. Infect Dis Poverty 2017; 6:41. [PMID: 28219418 PMCID: PMC5319148 DOI: 10.1186/s40249-017-0252-z] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2016] [Accepted: 01/27/2017] [Indexed: 02/02/2023] Open
Abstract
The clinical diagnosis of trichinellosis is difficult because its clinical manifestations are nonspecific. Detection of anti-Trichinella IgG by ELISA using T. spiralis muscle larval excretory-secretory (ES) antigens is the most commonly used serological method for diagnosis of trichinellosis, but the main disadvantage is false negativity during the early stage of infection. There is an obvious window period between Trichinella infection and antibody positivity. During the intestinal stage of Trichinella infection, the ES antigens of intestinal worms (intestinal infective larvae and adults) are exposed to host’s immune system at the earliest time and elicit the production of specific anti-Trichinella antibodies. Anti-Trichinella IgG antibodies in infected mice were detectable by ELISA with ES antigens of intestinal worms as soon as 8–10 days post infection (dpi), but ELISA with muscle larval ES antigens did not permit detection of infected mice before 12 dpi. Therefore, the new early antigens from T. spiralis intestinal worms should be screened, identified and characterized for early serodiagnosis of trichinellosis.
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Affiliation(s)
- Zhong-Quan Wang
- Department of Parasitology, Medical College, Zhengzhou University, Zhengzhou, 450052, China
| | - Ya-Li Shi
- Department of Parasitology, Medical College, Zhengzhou University, Zhengzhou, 450052, China
| | - Rou-Dan Liu
- Department of Parasitology, Medical College, Zhengzhou University, Zhengzhou, 450052, China
| | - Peng Jiang
- Department of Parasitology, Medical College, Zhengzhou University, Zhengzhou, 450052, China
| | - Ya-Yi Guan
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Key Laboratory of Parasite and Vector Biology, Ministry of Health, Shanghai, 200025, China
| | - Ying-Dan Chen
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Key Laboratory of Parasite and Vector Biology, Ministry of Health, Shanghai, 200025, China.
| | - Jing Cui
- Department of Parasitology, Medical College, Zhengzhou University, Zhengzhou, 450052, China.
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Liu RD, Qi X, Sun GG, Jiang P, Zhang X, Wang LA, Liu XL, Wang ZQ, Cui J. Proteomic analysis of Trichinella spiralis adult worm excretory-secretory proteins recognized by early infection sera. Vet Parasitol 2016; 231:43-46. [PMID: 27760716 DOI: 10.1016/j.vetpar.2016.10.008] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2016] [Revised: 09/27/2016] [Accepted: 10/07/2016] [Indexed: 10/20/2022]
Abstract
At the intestinal stage of a Trichinella spiralis (T. spiralis) infection, the excretory-secretory (ES) antigens produced by adult worms (AWs) result in an early exposure to the host's immune system and elicit the production of specific antibodies; the AW ES proteins might provide early diagnostic markers of trichinellosis. The aim of this study was to identify early serodiagnostic markers from T. spiralis AW ES antigens. T. spiralis AWs were collected at 72h post infection, and their ES antigens were analysed by SDS-PAGE and Western blot. Then, the immunoreactive bands were subjected to shotgun LC-MS/MS and bioinformatics analyses. Our results showed that only one protein band (33kDa) was recognized by the sera of mice infected with T. spiralis at 8 days after infection. The shotgun LC-MS/MS analysis identified 23 proteins that were then clustered into 10 types; these proteins had molecular weights of 28.13-71.62kDa and pI 5.05-9.20. Certain enzymes (e.g., serine protease, adult-specific deoxyribonuclease [DNase] II, peptidase S1A subfamily, and multi cystatin-like domain protein) were found to be highly represented. The functions of the 10 proteins were further analysed: of the 6 annotated proteins, 3 had serine hydrolase activity and 2 had DNase II activity. These results provide a valuable basis for identifying early diagnostic antigens and vaccine candidates for trichinellosis.
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Affiliation(s)
- Ruo Dan Liu
- Department of Parasitology, Medical College, Zhengzhou University, Zhengzhou 450052, PR China
| | - Xin Qi
- Department of Parasitology, Medical College, Zhengzhou University, Zhengzhou 450052, PR China
| | - Ge Ge Sun
- Department of Parasitology, Medical College, Zhengzhou University, Zhengzhou 450052, PR China
| | - Peng Jiang
- Department of Parasitology, Medical College, Zhengzhou University, Zhengzhou 450052, PR China
| | - Xi Zhang
- Department of Parasitology, Medical College, Zhengzhou University, Zhengzhou 450052, PR China
| | - Li Ang Wang
- Department of Parasitology, Medical College, Zhengzhou University, Zhengzhou 450052, PR China
| | - Xiao Lin Liu
- Department of Parasitology, Medical College, Zhengzhou University, Zhengzhou 450052, PR China
| | - Zhong Quan Wang
- Department of Parasitology, Medical College, Zhengzhou University, Zhengzhou 450052, PR China.
| | - Jing Cui
- Department of Parasitology, Medical College, Zhengzhou University, Zhengzhou 450052, PR China.
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9
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Sun GG, Wang ZQ, Liu CY, Jiang P, Liu RD, Wen H, Qi X, Wang L, Cui J. Early serodiagnosis of trichinellosis by ELISA using excretory-secretory antigens of Trichinella spiralis adult worms. Parasit Vectors 2015; 8:484. [PMID: 26394626 PMCID: PMC4579640 DOI: 10.1186/s13071-015-1094-9] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2015] [Accepted: 09/16/2015] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The excretory-secretory (ES) antigens of Trichinella spiralis muscle larvae (ML) are the most commonly used diagnostic antigens for trichinellosis. Their main disadvantage for the detection of anti-Trichinella IgG is false-negative results during the early stage of infection. Additionally, there is an obvious window between clinical symptoms and positive serology. METHODS ELISA with adult worm (AW) ES antigens was used to detect anti-Trichinella IgG in the sera of experimentally infected mice and patients with trichinellosis. The sensitivity and specificity were compared with ELISAs with AW crude antigens and ML ES antigens. RESULTS In mice infected with 100 ML, anti-Trichinella IgG were first detected by ELISA with the AW ES antigens, crude antigens and ML ES antigens 8, 12 and 12 days post-infection (dpi), respectively. In mice infected with 500 ML, specific antibodies were first detected by ELISA with the three antigen preparations at 10, 8 and 10 dpi, respectively. The sensitivity of the ELISA with the three antigen preparations for the detection of sera from patients with trichinellosis at 35 dpi was 100%. However, when the patients' sera were collected at 19 dpi, the sensitivities of the ELISAs with the three antigen preparations were 100% (20/20), 100% (20/20) and 75% (15/20), respectively (P < 0.05). The specificities of the ELISAs with the three antigen preparations were 98.11, 95.60 and 89.31%, respectively (P < 0.05). CONCLUSIONS The sensitivity and specificity of the T. spiralis AW ES antigens were superior to those of the AW crude antigens and ML ES antigens. Thus, the AW ES antigens might serve as potential antigens for the early and specific serodiagnosis of trichinellosis.
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Affiliation(s)
- Ge-Ge Sun
- Department of Parasitology, Medical College, Zhengzhou University, Zhengzhou, China.
| | - Zhong-Quan Wang
- Department of Parasitology, Medical College, Zhengzhou University, Zhengzhou, China.
| | - Chun-Ying Liu
- Department of Parasitology, Medical College, Zhengzhou University, Zhengzhou, China.
| | - Peng Jiang
- Department of Parasitology, Medical College, Zhengzhou University, Zhengzhou, China.
| | - Ruo-Dan Liu
- Department of Parasitology, Medical College, Zhengzhou University, Zhengzhou, China.
| | - Hui Wen
- Department of Parasitology, Medical College, Zhengzhou University, Zhengzhou, China.
| | - Xin Qi
- Department of Parasitology, Medical College, Zhengzhou University, Zhengzhou, China.
| | - Li Wang
- Department of Parasitology, Medical College, Zhengzhou University, Zhengzhou, China.
| | - Jing Cui
- Department of Parasitology, Medical College, Zhengzhou University, Zhengzhou, China.
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Sun GG, Liu RD, Wang ZQ, Jiang P, Wang L, Liu XL, Liu CY, Zhang X, Cui J. New diagnostic antigens for early trichinellosis: the excretory-secretory antigens of Trichinella spiralis intestinal infective larvae. Parasitol Res 2015; 114:4637-44. [PMID: 26342828 DOI: 10.1007/s00436-015-4709-3] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2015] [Accepted: 08/26/2015] [Indexed: 10/23/2022]
Abstract
The excretory-secretory (ES) antigens from Trichinella spiralis muscle larvae (ML) are the most commonly used diagnostic antigens for trichinellosis, but anti-Trichinella IgG antibodies cannot be detected until 2-3 weeks after infection; there is an obvious window period between Trichinella infection and antibody positivity. Intestinal infective larvae (IIL) are the first invasive stage during Trichinella infection, and their ES antigens are firstly exposed to the immune system and might be the early diagnostic markers of trichinellosis. The aim of this study was to evaluate the early diagnostic values of IIL ES antigens for trichinellosis. The IIL were collected from intestines of infected mice at 6 h postinfection (hpi), and IIL ES antigens were prepared by incubation for 18 h. Anti-Trichinella IgG antibodies in mice infected with 100 ML were detectable by ELISA with IIL ES antigens as soon as 10 days postinfection (dpi), but ELISA with ML ES antigens did not permit detection of infected mice before 12 dpi. When the sera of patients with trichinellosis at 19 dpi were assayed, the sensitivity (100 %) of ELISA with IIL ES antigens was evidently higher than 75 % of ELISA with ML ES antigens (P < 0.05) The specificity (96.86 %) of ELISA with IIL ES antigens was also higher than 89.31 % of ELISA with ML ES antigens (P < 0.05). The IIL ES antigens provided a new source of diagnostic antigens and could be considered as a potential early diagnostic antigen for trichinellosis.
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Affiliation(s)
- Ge Ge Sun
- Department of Parasitology, Medical College, Zhengzhou University, 40 Daxue Road, Zhengzhou, 450052, People's Republic of China
| | - Ruo Dan Liu
- Department of Parasitology, Medical College, Zhengzhou University, 40 Daxue Road, Zhengzhou, 450052, People's Republic of China
| | - Zhong Quan Wang
- Department of Parasitology, Medical College, Zhengzhou University, 40 Daxue Road, Zhengzhou, 450052, People's Republic of China.
| | - Peng Jiang
- Department of Parasitology, Medical College, Zhengzhou University, 40 Daxue Road, Zhengzhou, 450052, People's Republic of China
| | - Li Wang
- Department of Parasitology, Medical College, Zhengzhou University, 40 Daxue Road, Zhengzhou, 450052, People's Republic of China
| | - Xiao Lin Liu
- Department of Parasitology, Medical College, Zhengzhou University, 40 Daxue Road, Zhengzhou, 450052, People's Republic of China
| | - Chun Yin Liu
- Department of Parasitology, Medical College, Zhengzhou University, 40 Daxue Road, Zhengzhou, 450052, People's Republic of China
| | - Xi Zhang
- Department of Parasitology, Medical College, Zhengzhou University, 40 Daxue Road, Zhengzhou, 450052, People's Republic of China
| | - Jing Cui
- Department of Parasitology, Medical College, Zhengzhou University, 40 Daxue Road, Zhengzhou, 450052, People's Republic of China.
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