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1.
Exp Parasitol ; 223: 108080, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33548219

RESUMO

Schistosome parasites are complex trematode blood flukes responsible for the disease schistosomiasis; a global health concern prevalent in many tropical and sub-tropical countries. While established transcriptomic databases are accessed ad hoc to facilitate studies characterising specific genes or gene families, a more comprehensive systematic updating of gene annotation and survey of the literature to aid in annotation and context is rarely addressed. We have reanalysed an online transcriptomic dataset originally published in 2009, where seven life cycle stages of Schistosoma japonicum were examined. Using the online pathway analysis tool Reactome, we have revisited key data from the original study. A key focus of this study was to improve the interpretation of the gene expression profile of the developmental lung-stage schistosomula, since it is one of the principle targets for worm elimination. Highly enriched transcripts, associated with lung schistosomula, were related to a number of important biological pathways including host immune evasion, energy metabolism and parasitic development. Revisiting large transcriptomic databases should be considered in the context of substantial new literature. This approach could aid in the improved understanding of the molecular basis of parasite biology. This may lead to the identification of new targets for diagnosis and therapies for schistosomes, and other helminths.


Assuntos
Estágios do Ciclo de Vida , Pneumopatias Parasitárias/parasitologia , Pulmão/parasitologia , Schistosoma japonicum/crescimento & desenvolvimento , Esquistossomose Japônica/parasitologia , Transcriptoma/fisiologia , Análise de Variância , Animais , Degranulação Celular/fisiologia , Conjuntos de Dados como Assunto , Proteínas Facilitadoras de Transporte de Glucose/fisiologia , Interações Hospedeiro-Parasita , Pneumopatias Parasitárias/imunologia , Neutrófilos/fisiologia , Fator 1 de Elongação de Peptídeos/fisiologia , Schistosoma japonicum/genética , Schistosoma japonicum/imunologia , Esquistossomose Japônica/imunologia
3.
Am J Trop Med Hyg ; 103(1_Suppl): 50-57, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32400344

RESUMO

The Schistosomiasis Consortium for Operational Research and Evaluation (SCORE) was funded in 2008 to conduct research that would support country schistosomiasis control programs. As schistosomiasis prevalence decreases in many places and elimination is increasingly within reach, a sensitive and specific test to detect infection with Schistosoma mansoni and Schistosoma haematobium has become a pressing need. After obtaining broad input, SCORE supported Leiden University Medical Center (LUMC) to modify the serum-based antigen assay for use with urine, simplify the assay, and improve its sensitivity. The urine assay eventually contributed to several of the larger SCORE studies. For example, in Zanzibar, we demonstrated that urine filtration, the standard parasite egg detection diagnostic test for S. haematobium, greatly underestimated prevalence in low-prevalence settings. In Burundi and Rwanda, the circulating anodic antigen (CAA) assay provided critical information about the limitations of the stool-based Kato-Katz parasite egg-detection assay for S. mansoni in low-prevalence settings. Other SCORE-supported CAA work demonstrated that frozen, banked urine specimens yielded similar results to fresh ones; pooling of specimens may be a useful, cost-effective approach for surveillance in some settings; and the assay can be performed in local laboratories equipped with adequate centrifuge capacity. These improvements in the assay continue to be of use to researchers around the world. However, additional work will be needed if widespread dissemination of the CAA assay is to occur, for example, by building capacity in places besides LUMC and commercialization of the assay. Here, we review the evolution of the CAA assay format during the SCORE period with emphasis on urine-based applications.


Assuntos
Antígenos de Helmintos/imunologia , Glicoproteínas/imunologia , Proteínas de Helminto/imunologia , Schistosoma/imunologia , Esquistossomose/diagnóstico , Animais , Biomarcadores , Burundi/epidemiologia , Criança , Testes Diagnósticos de Rotina , Fezes/parasitologia , Feminino , Humanos , Testes Imunológicos , Masculino , Modelos Animais , Papio/parasitologia , Contagem de Ovos de Parasitas , Prevalência , Ruanda/epidemiologia , Santa Lúcia/epidemiologia , Schistosoma/isolamento & purificação , Schistosoma haematobium/imunologia , Schistosoma haematobium/isolamento & purificação , Schistosoma japonicum/imunologia , Schistosoma japonicum/isolamento & purificação , Schistosoma mansoni/imunologia , Schistosoma mansoni/isolamento & purificação , Esquistossomose/epidemiologia , Sensibilidade e Especificidade , Tanzânia/epidemiologia , Urina/parasitologia
4.
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi ; 32(3): 262-267, 2020 May 08.
Artigo em Chinês | MEDLINE | ID: mdl-32468788

RESUMO

OBJECTIVE: To investigate the immunological functions of heat shock protein 40 kDa of Schistosoma japonicum (SjHSP40). METHODS: The homology of the SjHSP40 protein sequence was analyzed and the B and T cell epitopes of SjHSP40 were predicted using bioinformatics tools. The full-length SjHSP40 gene was amplified using a PCR assay, and cloned into the prokaryotic expression vector pGEX-6P-1, which was transformed into Escherichia coli BL-21. The protein expression was induced with isopropyl ß-D-thiogalactoside (IPDG), and then, the recombinant protein was purified with glutathione-sepharose 4B resin to yield the fusion protein GST-SjHSP40, which was checked with SDS-PAGE and Western blotting. Following immunization with GST-SjHSP40, the serum levels of anti-SjHSP40 IgG antibody and IgG1 and IgG2a subtypes were detected in BALB/c mice using ELISA. In addition, the effect of SjHSP40 on CD4+ T-cell subset differentiation was examined using flow cytometry. RESULTS: SjHSP40 contained 7 potential B cell epitopes and multiple T cell epitopes (CTL epitopes and Th epitopes). The prokaryotic expression plasmid pGEX-6p-1-SjSHP40 was successfully constructed, and the fusion protein GST-SjHSP40 was obtained following IPDG induction and protein purification. Significantly higher serum levels of anti-SjHSP40 IgG, IgG1 and IgG2a antibodies were detected in mice immunized with GST-SjHSP40 than in other groups; however, SjHSP40 showed no remarkable effects on CD4+ T-cell subset differentiation. CONCLUSIONS: SjHSP40 may induce specific humoral immune responses in mice; however, it does not affect the balance of Th immune responses. It is suggested that SjHSP40 may be a potential vaccine candidate.


Assuntos
Proteínas de Choque Térmico HSP40 , Schistosoma japonicum , Animais , Anticorpos Anti-Helmínticos/sangue , Biologia Computacional , Epitopos/imunologia , Proteínas de Choque Térmico HSP40/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Plasmídeos , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Schistosoma japonicum/genética , Schistosoma japonicum/imunologia
5.
Parasitol Res ; 119(4): 1317-1325, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32152713

RESUMO

Programmed cell death protein 10 (PCDP10) is widely distributed in animal tissues and exerts extensive biological effects. This study aimed to investigate the effect of Schistosoma japonicum PCDP10 (SjPCDP10) on the fecundity of schistosomes. We performed real-time PCR to assess Sjpcdp10 expression levels at different developmental stages of S. japonicum. Immunoprotection against S. japonicum was assessed in vivo in mice, and Sjpcdp10 expression was inhibited via RNA interference (RNAi) to determine its role in fecundity. Real-time PCR analysis revealed that Sjpcdp10 mRNA was expressed during different developmental stages in S. japonicum, reaching maximum and minimum levels in female worms and lung-stage schistosomula, respectively. Recombinant SjPCDP10 had a molecular weight of approximately 28 kDa, displaying good immunogenicity but poor immunoprotection. SjPCDP10 was primarily localized in the egg, eggshell, epiphragm of adult worms, and especially the vitelline glands of female worms. RNAi-mediated knockdown of Sjpcdp10 by greater than 90%, and the protein expression decreased by 73%, reduced the number of eggs per female worm significantly more than RNAi-mediated knockdown of Egfp (negative control) (P < 0.05). The present results indicate that Sjpcdp10 knockdown affects the fecundity of schistosomes and may play a vital role in oogenesis.


Assuntos
Proteínas Reguladoras de Apoptose/genética , Fertilidade/genética , Proteínas de Helminto/genética , Schistosoma japonicum/imunologia , Animais , Proteínas Reguladoras de Apoptose/metabolismo , Feminino , Proteínas de Fluorescência Verde/genética , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos ICR , Interferência de RNA , RNA Mensageiro , RNA Interferente Pequeno/genética , Coelhos , Reação em Cadeia da Polimerase em Tempo Real , Schistosoma japonicum/genética , Schistosoma japonicum/parasitologia
6.
Parasitol Res ; 119(5): 1619-1628, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32185481

RESUMO

Schistosomiasis is still prevalent and seriously endangering the health of people and livestock in many countries. There have been great efforts to develop vaccines against schistosomiasis for prolonged protection in epidemic areas. Molecules from lung-stage schistosomula have been regarded as potential vaccine candidates against schistosomiasis. Our previous work has shown that cathepsin L3 from Schistosoma japonicum (SjCL3) is expressed in lung-stage schistosomula, but its role is not well known. In the present study, we characterized SjCL3 and detected its effect as a possible vaccine in vivo and in vitro. From the results of quantitative PCR (qPCR) and western blot, SjCL3 was present throughout the lifecycle of the worm, and its relative expressed level was higher in the liver eggs and adult worms than other stages. Additionally, immunofluorescence assay showed that SjCL3 was mainly concentrated in the eggshell, alimentary canal, and musculature of worms. Compared with the adjuvant group, the immunization of SjCL3 in mice resulted in a 28.9% decrease in worm burden and a 29.2% reduction in egg number in the host liver. In antibody-dependent cell-mediated cytotoxicity (ADCC) insecticidal experiments in vitro, the existence of SjCL3 could in part suppress adherence between macrophages and worm. The above results indicated that the immunization of SjCL3 could induce limited immune protection against S. japonicum infection in mice, and this protease played a role in breaking the process of ADCC, which was beneficial to the survival of worms.


Assuntos
Catepsinas/imunologia , Vacinas Protozoárias/imunologia , Schistosoma japonicum/imunologia , Esquistossomose Japônica/prevenção & controle , Adjuvantes Imunológicos , Animais , Citotoxicidade Celular Dependente de Anticorpos/imunologia , Western Blotting , Clonagem Molecular , Feminino , Macrófagos/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Schistosoma japonicum/metabolismo , Esquistossomose Japônica/imunologia , Vacinação
7.
PLoS One ; 15(2): e0229542, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32107503

RESUMO

BACKGROUND: The development of a schistosome vaccine has proved challenging but we have suggested that characterisation of the self-cure mechanism in rhesus macaques might provide a route to an effective product. The schistosome esophagus is a complex structure where blood processing is initiated by secretions from anterior and posterior glands, achieved by a mixture of ~40 unique proteins. The mechanism of self-cure in macaques involves cessation of feeding, after which worms slowly starve to death. Antibody coats the esophagus lumen and disrupts the secretory processes from the glands, potentially making their secretions ideal vaccine targets. METHODOLOGY/PRINCIPAL FINDINGS: We have designed three peptide arrays comprising overlapping 15-mer peptides encompassing 32 esophageal gland proteins, and screened them for reactivity against 22-week infection serum from macaques versus permissive rabbit and mouse hosts. There was considerable intra- and inter-species variation in response and no obvious unique target was associated with self-cure status, which suggests that self-cure is achieved by antibodies reacting with multiple targets. Some immuno-dominant sequences/regions were evident across species, notably including: MEGs 4.1C, 4.2, and 11 (Array 1); MEG-12 and Aspartyl protease (Array 2); a Tetraspanin 1 loop and MEG-n2 (Array 3). Responses to MEGs 8.1C and 8.2C were largely confined to macaques. As proof of principle, three synthetic genes were designed, comprising several key targets from each array. One of these was expressed as a recombinant protein and used to vaccinate rabbits. Higher antibody titres were obtained to the majority of reactive regions than those elicited after prolonged infection. CONCLUSIONS/SIGNIFICANCE: It is feasible to test simultaneously the additive potential of multiple esophageal proteins to induce protection by combining their most reactive regions in artificial constructs that can be used to vaccinate suitable hosts. The efficacy of the approach to disrupt esophageal function now needs to be tested by a parasite challenge.


Assuntos
Antígenos de Helmintos , Schistosoma japonicum/imunologia , Vacinas Sintéticas/imunologia , Sequência de Aminoácidos , Animais , Anticorpos Anti-Helmínticos/biossíntese , Anticorpos Anti-Helmínticos/sangue , Antígenos de Helmintos/genética , Modelos Animais de Doenças , Mapeamento de Epitopos , Epitopos/genética , Esôfago/imunologia , Genes de Helmintos , Genes Sintéticos , Proteínas de Helminto/genética , Proteínas de Helminto/imunologia , Macaca mulatta , Camundongos , Análise Serial de Proteínas , Coelhos , Ratos , Schistosoma japonicum/genética , Esquistossomose Japônica/imunologia , Esquistossomose Japônica/prevenção & controle , Vacinas Sintéticas/genética
8.
PLoS One ; 15(1): e0228184, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31995591

RESUMO

BACKGROUND: The existing diagnostic techniques for detecting schistosomiasis turkestanica, such as aetiological assays, identify infection by parasitic worms via the incubation of miracidia from faeces or observing eggs under microscopy. However, they are limited in the diagnosis of low-grade and prepatent infections, which lead to a high misdetection rates. Therefore, a new method for parasite diagnosis with increased sensitivity is urgently needed. METHODS: Goats in Nimu County (Tibet, China) infected with Schistosoma turkestanicum in an epidemic area were selected according positivity for the infection by faecal examination. Adult worms were collected, eggs were extracted by the sodium hydroxide (NaOH) erosion method, and soluble worm antigen preparation (SWAP) and soluble egg antigen (SEA) were isolated. The best coating concentration of the antigens and the best degree of dilution for serum were determined by square array experiments, and the optimal blocking solution and serum diluents were selected. The specificity, sensitivity and crossover of the ELISA method were determined using 48 samples of goat sera positive for S. turkestanicum, 100 samples of goat sera negative for S. turkestanicum, and 54 samples of buffalo sera positive for S. japonicum. Serological assays were established with samples from goats naturally grazed in a rural area of Nimu County, Tibet Province, by using the indirect ELISA method for the diagnosis of schistosomiasis, and faeces were collected for miracidia hatching. The sensitivity of the two detection methods was compared. RESULTS: Eggs of S. turkestanicum were distributed in the host duodenum and small intestine. Eggs in the host intestinal wall were extracted by the NaOH erosion method, which provided intact eggs with reduced impurities. The testing results obtained by isolating SEA were more stable than those obtained by using SWAP and less affected by the coating concentration and serum dilution. Additionally, the value of positive serum/negative (P/N) serum for SEA was much higher than that for SWAP. The optimal coating concentration of SEA was 0.5 µg/ml, and the optimal serum dilution was 1:100. The specificity and sensitivity of the indirect ELISA based on SEA (S. turkestanicum) were both 100%, and no cross-reactivity was found with schistosomiasis japonica. An epidemiological survey of goats in naturally infected areas showed that the prevalence rate of schistosomiasis turkestanica was 93%, and the infection rate increased with the ages of the goats. CONCLUSION: We aimed to develop a sensitive method to utilize in the mass field screening of livestock. As a diagnostic antigen, SEA (S. turkestanicum) was more suitable for serological testing than SWAP (S. turkestanicum). The indirect ELISA using SEA (S. turkestanicum) exhibited good sensitivity, specificity and no cross-reactivity with schistosomiasis japonica. The degree of infectivity and prevalence of S. turkestanicum infection in endemic areas are serious and should be a focus of concern among local departments.


Assuntos
Antígenos de Helmintos/imunologia , Ensaio de Imunoadsorção Enzimática/veterinária , Schistosoma , Esquistossomose/veterinária , Testes Sorológicos/veterinária , Animais , Reações Cruzadas/imunologia , Doenças das Cabras/diagnóstico , Doenças das Cabras/parasitologia , Cabras/parasitologia , Óvulo/imunologia , Schistosoma/imunologia , Schistosoma japonicum/imunologia , Esquistossomose/diagnóstico , Esquistossomose/imunologia , Sensibilidade e Especificidade , Tibet
9.
Acta Trop ; 202: 105285, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31786108

RESUMO

Dipstick Dye Immunoassay (DDIA) and Indirect Haemagglutination Assay (IHA), are two commercially available kits which have been widely used for screening Schistosoma japonicum in P.R. China. Whether they can be used for screening of Schistosoma haematobium are not clear. In order to evaluate the diagnostic efficiency of DDIA and IHA for screening Schistosoma haematobium, serum samples were collected from pupils in endemic areas in Zambia, Southern Africa, and tested by DDIA and IHA by single-blind manner. Meanwhile, the pupils were microscopically examined by infection with Schistosoma and soil-transmitted helminths, visually observed for parasite eggs. Of the enrolled 148 pupils, 61% tested positive for S. haematobium infection, while 31% and 36% of pupils were infected with hookworm and Ascaris respectively. Regarding the parasitological tests as reference standard, for the diagnosis of S. haematobium infection, IHA performed higher sensitivity (74%, 95% CI: 65%-83%) than that of DDIA (60%, 95%CI: 49%-70%). The sensitivities of IHA and DDIA are significant higher in 10-14 years old students than those of 7-9 years old group. The specificity of DDIA and IHA were 61% (95%CI: 49%-74%) and 72% (95%CI: 60%-84%), respectively. The co-infection with STHs decreased the specificity of DDIA but had no impact on that of IHA. Our study indicated that IHA has more potential as an alternative diagnostic tool for identifying schistosomiasis haematobium but need further improvement.


Assuntos
Anticorpos Anti-Helmínticos/sangue , Schistosoma haematobium/imunologia , Schistosoma japonicum/imunologia , Esquistossomose Urinária/diagnóstico , Esquistossomose Japônica/diagnóstico , Adolescente , Animais , Criança , Coinfecção , Feminino , Testes de Hemaglutinação , Humanos , Imunoensaio , Masculino , Programas de Rastreamento , Esquistossomose Urinária/sangue , Esquistossomose Urinária/imunologia , Esquistossomose Japônica/epidemiologia , Sensibilidade e Especificidade , Método Simples-Cego , Zâmbia
10.
Acta Trop ; 202: 105239, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31669534

RESUMO

Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) is a candidate subunit vaccine that induces protective immunity and elicits partial resistance to Schistosoma japonicum upon mouse and livestock vaccination. This study aimed to evaluate the effect of regulatory T cells (Tregs), which were defined as CD4+CD25+Foxp3+ cells, on the efficacy of a GAPDH vaccine against S. japonicum. BALB/c female mice were randomly divided into five groups as follows: normal, infected control, anti-CD25 monoclonal antibody (anti-CD25 mAb), GAPDH group, and co-treated with anti-CD25 mAb and GAPDH group. The worm reduction and liver egg reduction rates in the GAPDH group were 32.46% and 35.43%, respectively, which increased to 60.09% and 58.78%, respectively, after anti-CD25 mAb administration. Compared with those in the infected control group, the percentage of Tregs in the spleen decreased significantly when GAPDH and anti-CD25 mAb were used either alone or in combination. Furthermore, secretions associated with the Th1 response increased in splenocytes of the anti-CD25 mAb group, whereas the Th1 and Th2 responses increased in splenocytes of the GAPDH and co-treated groups. Compared to that in the infected control group, granuloma diameter in the GAPDH and co-treated groups increased slightly, but there were no significant differences among the groups. Our results indicate that the protective effect of the GAPDH vaccines can be improved by decreasing Tregs and enhancing the Th1- and Th2-type immune responses. Therefore, anti-CD25 mAb and GAPDH might exert synergistic effects to clear parasites by decreasing the frequency of Tregs and increasing the Th1- and Th2-type immune responses.


Assuntos
Gliceraldeído-3-Fosfato Desidrogenases/imunologia , Schistosoma japonicum/imunologia , Linfócitos T Reguladores/imunologia , Vacinas/imunologia , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/uso terapêutico , Citocinas/imunologia , Feminino , Granuloma/patologia , Subunidade alfa de Receptor de Interleucina-2/imunologia , Fígado/imunologia , Fígado/patologia , Camundongos , Camundongos Endogâmicos BALB C , Esquistossomose Japônica/parasitologia , Esquistossomose Japônica/prevenção & controle , Linfócitos T Reguladores/efeitos dos fármacos
11.
Med Sci Monit ; 25: 9319-9326, 2019 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-31811711

RESUMO

BACKGROUND Schistosomiasis is one of the most important infectious parasitic diseases in the world. The most important was to control schistosomiasis is through a combination of medical therapy and immunization. The membrane antigens Tsp2 and 29 from Schistosoma are promising anti-schistosomiasis vaccine candidates. MATERIAL AND METHODS In this study, the pcDNA3.1(+)-SjTsp2, pcDNA3.1(+)-Sj29, and pcDNA3.1 (+)-SjTsp2-29 eukaryotic expression vectors were successfully constructed as DNA vaccines, and the protective abilities of these vaccines were evaluated in mice. RESULTS The results showed that vaccination with SjTsp2, Sj29, and SjTsp2-29 reduced parasite burden and hepatic pathology compared to the control group, and the protective effect of the bivalent SjTsp2-29 DNA vaccine was better than that of the univalent SjTsp2 or Sj29 DNA vaccines. We also found high levels of IgG, IgG1, and IgG2a against SjTsp2, Sj29, and SjTsp2-29 DNA vaccines, with high expression of IFN-γ and no IL-4 in the mice. CONCLUSIONS The double-membrane antigen DNA vaccine SjTsp2-29 elicited protection against Schistosoma infection and might serve as a vaccine candidate.


Assuntos
Schistosoma japonicum/imunologia , Esquistossomose/terapia , Vacinas de DNA/farmacologia , Animais , Anticorpos Anti-Helmínticos , China , Feminino , Imunização , Proteínas de Membrana , Camundongos , Camundongos Endogâmicos , Schistosoma japonicum/metabolismo , Esquistossomose/imunologia , Trombospondinas/imunologia , Vacinação
12.
Int J Parasitol ; 49(13-14): 993-997, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31726056

RESUMO

Extracellular vesicles are critical regulators of host-parasite interactions. We previously demonstrated that Schistosoma japonicum EVs contain a remarkably high abundance of host miR-148a. Here, we characterised the abundance of miR-148a in circulation, in peripheral immune cells, and in plasma EVs of S. japonicum-infected mice. The results suggested the high abundance of miR-148a in macrophages to be likely linked to S. japonicum EVs. Additionally, miR-148a was found to target PTEN through the PI3K/AKT pathway to regulate cytokine production in macrophages. Consequently, our findings suggest that high abundance of miR-148a in macrophages may be associated with S. japonicum EVs, and regulate the host immune response during schistosome infection.


Assuntos
Interações Hospedeiro-Parasita , Imunidade Celular , Macrófagos/imunologia , MicroRNAs/metabolismo , Schistosoma japonicum/imunologia , Esquistossomose Japônica/imunologia , Animais , Modelos Animais de Doenças , Vesículas Extracelulares/química , Regulação da Expressão Gênica , Macrófagos/química , Camundongos , Schistosoma japonicum/crescimento & desenvolvimento
13.
Parasit Vectors ; 12(1): 507, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31666115

RESUMO

BACKGROUND: The identification and characterization of epitopes facilitate the discovery and development of new therapeutics, vaccines and diagnostics for infectious diseases. In this study, we developed a glutathione S-transferase (GST)-peptide fusion protein microplate array for the identification of linear B-cell epitopes and applied this novel method to the identification of linear B-cell epitopes of SjSP-13, an immunodiagnostic biomarker of schistosomiasis japonica. METHODS: SjSP-13 was divided into 17 overlapped peptides (p1-17), and the coding sequence of each peptide was obtained by annealing two complementary oligonucleotides. SjSP-13 peptides were expressed by fusion with an N-terminal GST tag and a C-terminal 6xHis tag. The GST-peptide-His fusion protein was specifically bound to the Immobilizer Glutathione MicroWell 96-well plates without purification. SjSP-13 peptides and core epitopes that could be recognized by sera from schistosomiasis patients were identified by ELISA and confirmed by Western blot analysis. The receiver operating characteristic (ROC) analysis was performed to determine the diagnostic validity of the identified peptide. RESULTS: Full-length GST-peptide-His fusion proteins were successfully expressed and specifically bound to the Immobilizer Glutathione MicroWell 96-well plates. Two adjacent peptides (p7 and p8) were found to be highly immunogenic in humans. The core epitope of p7 and p8 is an 11-aa peptide (80KCLDVTDNLPE90) and an 8-aa peptide (90EKIIQFAE97), respectively. The area under the ROC curve (AUC) value of the peptide which contains the two identified epitopes is 0.947 ± 0.019. The diagnostic sensitivity and specificity of the peptide is 76.7% (95% CI: 68.8-84.5%) and 100%, respectively. CONCLUSIONS: 90EKIIQFAE97 and 80KCLDVTDNLPE90 are the two linear epitopes of SjSP-13 recognized by patient sera, and could be potential serological markers for schistosomiasis japonica.


Assuntos
Epitopos/análise , Glutationa Transferase/imunologia , Proteínas de Helminto/imunologia , Peptídeos/imunologia , Schistosoma japonicum/imunologia , Animais , Área Sob a Curva , Western Blotting , Epitopos/genética , Glutationa Transferase/química , Glutationa Transferase/genética , Proteínas de Helminto/genética , Humanos , Biblioteca de Peptídeos , Peptídeos/química , Peptídeos/genética , Análise Serial de Proteínas , Sinais Direcionadores de Proteínas/genética , Curva ROC , Schistosoma japonicum/genética , Sensibilidade e Especificidade
14.
Infect Immun ; 87(12)2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31570558

RESUMO

Schistosomiasis is a parasitic helminth disease that can cause severe inflammatory pathology, leading to organ damage, in humans. During a schistosomal infection, the eggs are trapped in the host liver, and products derived from eggs induce a polarized Th2 cell response, resulting in granuloma formation and eventually fibrosis. Previous studies indicated that the nucleotide-binding oligomerization domain-, leucine-rich repeat-, and pyrin domain-containing protein 3 (NLRP3) inflammasome is involved in schistosomiasis-associated liver fibrosis and that taurine could ameliorate hepatic granulomas and fibrosis caused by Schistosoma japonicum infection. Nevertheless, the precise role and molecular mechanism of the NLRP3 inflammasome and the protective effects of taurine in S. japonicum infection have not been extensively studied. In this study, we investigated the role of the NLRP3 inflammasome and the hepatoprotective mechanism of taurine in schistosoma-induced liver injury in mice. NLRP3 deficiency ameliorated S. japonicum-infection-induced hepatosplenomegaly, liver dysfunction, and hepatic granulomas and fibrosis; it also reduced NLRP3-dependent liver pyroptosis. Furthermore, taurine suppressed hepatic thioredoxin-interacting protein (TXNIP)/NLRP3 inflammasome activation in mice with S. japonicum infections, thereby inhibiting the activation of downstream inflammatory mediators such as interleukin-1ß and subsequent pyroptosis. Our results suggest that the TXNIP/NLRP3 inflammasome pathway and mediating pyroptosis are involved in S. japonicum-induced liver injury and may be a potential therapeutic target for schistosomiasis treatment. In addition, taurine may be useful to alleviate or to prevent the occurrence of schistosomiasis-associated liver fibrosis.


Assuntos
Proteínas de Transporte/antagonistas & inibidores , Inflamassomos/antagonistas & inibidores , Proteína 3 que Contém Domínio de Pirina da Família NLR/antagonistas & inibidores , Schistosoma japonicum/imunologia , Esquistossomose Japônica/imunologia , Taurina/farmacologia , Tiorredoxinas/antagonistas & inibidores , Animais , Modelos Animais de Doenças , Fígado/lesões , Fígado/parasitologia , Cirrose Hepática/parasitologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Piroptose/imunologia , Esquistossomose Japônica/parasitologia , Transdução de Sinais/imunologia
15.
Parasit Vectors ; 12(1): 475, 2019 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-31610797

RESUMO

BACKGROUND: Inflammation-induced dysfunction of hepatic stellate cells (HSCs) is involved in schistosomiasis-associated liver fibrosis, and soluble egg antigen (SEA) is a crucial pathogen-associated molecular pattern associated with liver injury in schistosomiasis. In addition, numerous studies have shown that caspase-1-mediated pyroptosis participates in the development of multiple inflammation-related diseases. However, whether pyroptotic cell death of HSCs is involved in SEA-mediated liver damage is not well understood. METHODS: Primary cultured HSCs and Schistosoma japonicum-infected mouse liver tissue were analysed for histological changes and caspase-1 activation, and the role of pyroptosis in the mechanisms underlying SEA-induced HSC death was investigated. Accumulation of reactive oxygen species (ROS) in infected livers and SEA-stimulated HSCs was measured by flow cytometry and immunofluorescence. RESULTS: Caspase-1 activity was elevated in both liver tissues and HSCs of S. japonicum-infected mice. Furthermore, SEA stimulation increased the proportion of pyroptotic HSCs, as shown by lactate dehydrogenase (LDH) release assays and by flow cytometric analysis of propidium iodide (PI) and caspase-1 double staining in cells. In addition, ROS generation was elevated in infected liver tissues and SEA-stimulated HSCs, and ROS inhibition downregulated SEA-induced caspase-1 activation and pyroptosis in HSCs. CONCLUSIONS: Our present study demonstrates that pyroptotic cell death in HSCs induced by SEA via ROS-mediated caspase-1 activation may serve as a significant mechanism to initiate the inflammatory response and thereby exacerbate liver injury during S. japonicum infection.


Assuntos
Antígenos de Helmintos/fisiologia , Células Estreladas do Fígado/fisiologia , Piroptose/fisiologia , Espécies Reativas de Oxigênio/imunologia , Schistosoma japonicum/imunologia , Análise de Variância , Animais , Caspase 1/genética , Caspase 1/metabolismo , Feminino , Imunofluorescência , Células Estreladas do Fígado/citologia , Células Estreladas do Fígado/enzimologia , Células Estreladas do Fígado/metabolismo , Imuno-Histoquímica , Fígado/enzimologia , Fígado/metabolismo , Fígado/parasitologia , Fígado/patologia , Cirrose Hepática/enzimologia , Cirrose Hepática/patologia , Camundongos , Camundongos Endogâmicos C57BL , Espécies Reativas de Oxigênio/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Schistosoma japonicum/metabolismo , Esquistossomose Japônica/enzimologia , Esquistossomose Japônica/etiologia , Esquistossomose Japônica/patologia , Caramujos/parasitologia
16.
Front Immunol ; 10: 2154, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31572373

RESUMO

CD4+ T follicular helper (Tfh) cells, a new subset of immune cells, have been demonstrated to be involved in granulomatous responses to Schistosoma japonicum (S. japonicum) infection. However, the role and underlying mechanisms of Tfh cell aggregation in S. japonicum infection remain incompletely understood. In this study, we provide evidence that S. japonicum infection enhances the accumulation of Tfh cells in the spleen, lymph nodes, and peripheral blood of C57BL/6 mice. Infection-induced Tfh cells exhibited more potent effects directly on B cell responses than the control Tfh cells (P < 0.05). Furthermore, reduced apoptosis of Tfh cells was found both in S. japonicum infected mice and in soluble egg antigen (SEA) treated Tfh cells (P < 0.05). Mechanistic studies reveal that caspase-3 is the primary drivers of down-regulated apoptotic Tfh cell death in S. japonicum infection. In summary, this study demonstrates that Tfh cell accumulation might have an impact on the generation of immune responses in S. japonicum infection, and caspase-3 signaling mediated apoptosis down-regulation might responsible for the accumulation of Tfh cell in this course.


Assuntos
Apoptose/imunologia , Caspase 3/imunologia , Schistosoma japonicum/imunologia , Esquistossomose Japônica/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Animais , Caspase 3/metabolismo , Regulação para Baixo/imunologia , Feminino , Linfonodos/imunologia , Linfonodos/metabolismo , Linfonodos/parasitologia , Camundongos Endogâmicos C57BL , Schistosoma japonicum/fisiologia , Esquistossomose Japônica/metabolismo , Esquistossomose Japônica/parasitologia , Baço/imunologia , Baço/metabolismo , Baço/parasitologia , Linfócitos T Auxiliares-Indutores/metabolismo , Linfócitos T Auxiliares-Indutores/parasitologia
17.
Acta Trop ; 200: 105186, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31542371

RESUMO

The small blood flukes of genus Schistosoma, which cause one of the most prevalent and serious parasitic zoonosis schistosomiasis, are dependent on immune-related factors of their mammalian host to facilitate their growth and development, and the formation of granulomatous pathology caused by eggs deposited in host's liver and intestinal wall. Schistosome development is hampered in the mice lacking just T cells, and is even more heavily retarded in the severe combined immunodeficient (SCID) mice lacking both T and B lymphocytes. Nevertheless, it's still not clear about the underlying regulatory molecular mechanisms of schistosome growth and development by host's immune system. This study, therefore, detected and compared the serum metabolic profiles between the immunodeficient mice and immunocompetent mice (SCID mice vs. BALB/c mice) before and after S. japonicum infection (on the thirty-fifth day post infection using liquid chromatography-mass spectrometry (LC-MS). Totally, 705 ion features in electrospray ionization in positive-ion mode (ESI+) and 242 ion features in ESI- mode were identified, respectively. First, distinct serum metabolic profiles were identified between SCID mice and BALB/c mice without S. japonicum worms infection. Second, uniquely perturbed serum metabolites and their enriched pathways were also obtained between SCID mice and BALB/c mice after S. japonicum infection, which included differential metabolites due to both species differences and differential responses to S. japonicum infection. The metabolic pathways analysis revealed that arachidonic acid metabolism, biosynthesis of unsaturated fatty acids, linoleic acid metabolism, glycosylphosphatidylinositol (GPI)-anchor biosynthesis, alpha-linolenic acid metabolism, glycerophospholipid metabolism, sphingolipid metabolism and purine metabolism were enriched based on the differential serum metabolites between SCID mice and BALB/c mice after S. japonicum infection, which was addressed to be related to the retarded growth and development of S. japonicum in SCID mice. These findings provide new clues to the underlying molecular events of host's systemic metabolic changes on the growth and development of S. japonicum worms, and also provide quite promising candidates for exploitation of drugs or vaccines against schistosome and schistosomiasis.


Assuntos
Metabolômica , Camundongos Endogâmicos BALB C/crescimento & desenvolvimento , Camundongos SCID/crescimento & desenvolvimento , Schistosoma japonicum/imunologia , Esquistossomose Japônica/imunologia , Soro/imunologia , Soro/metabolismo , Animais , Feminino , Camundongos , Camundongos Endogâmicos BALB C/metabolismo , Camundongos SCID/metabolismo
18.
Parasitol Res ; 118(9): 2601-2608, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31377909

RESUMO

In this study, the diagnostic value of Schistosoma japonicum cathepsin B (SjCatB) was evaluated as an antigen for the early detection of S. japonicum infection. SjCatB is a key protease used by the cercaria to penetrate the intact skin of the host for transdermal infection. The early exposure of the host's immune system to this enzyme may elicit early production of antibodies against this molecule. Therefore, the recombinant SjCatB (rSjCatB) was expressed in Escherichia coli with N-terminal 6xHis-tag. rSjCatB was tested for its performance as a diagnostic antigen using indirect enzyme-linked immunosorbent assay (ELISA) with sera from experimentally infected mice collected at > 8 weeks post-infection. Showing 100% sensitivity and 95.0% specificity in the ELISA, rSjCatB was then evaluated with sera from experimentally infected mice collected at 1-7 weeks post-infection to determine how early the antibodies can be detected. Results showed that as early as 6 weeks post-infection, 2 of the 3 infected mice were found to be positive with the antibodies against SjCatB. Furthermore, the potential of the recombinant antigen in detecting human schistosomiasis was evaluated with archived serum samples collected from individuals who had been diagnosed with S. japonicum infection by stool examination. Results showed 86.7% sensitivity and 96.7% specificity suggesting its high diagnostic potential for human schistosomiasis. In addition, SjCatB showed minimal cross-reaction with the sera collected from patients with other parasitic diseases. In conclusion, the results of this study suggest that SjCatB will be useful in the development of a sensitive and specific early detection test for S. japonicum infection.


Assuntos
Catepsina B/análise , Ensaio de Imunoadsorção Enzimática/métodos , Schistosoma japonicum/enzimologia , Esquistossomose Japônica/diagnóstico , Animais , Anticorpos Anti-Helmínticos/sangue , Anticorpos Anti-Helmínticos/imunologia , Antígenos de Helmintos/análise , Antígenos de Helmintos/genética , Antígenos de Helmintos/imunologia , Ásia , Catepsina B/genética , Catepsina B/imunologia , Reações Cruzadas , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos ICR , Schistosoma japonicum/genética , Schistosoma japonicum/imunologia , Schistosoma japonicum/isolamento & purificação , Esquistossomose Japônica/sangue , Esquistossomose Japônica/parasitologia , Sensibilidade e Especificidade , Zoonoses/sangue , Zoonoses/diagnóstico , Zoonoses/parasitologia
19.
J Vet Med Sci ; 81(10): 1413-1418, 2019 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-31391359

RESUMO

Humans and dogs live very close together and share various pathogens causing zoonotic parasitoses like schistosomiasis. A previous population genetics study done for schistosomes in the Philippines suggested that there is a high transmission level of Schistosoma japonicum among humans and dogs proving that the latter are important reservoirs for this zoonotic parasite. A more sensitive and specific test detecting schistosome infection in dogs will therefore strengthen the zoonotic surveillance, which might help in the possible elimination of this ancient disease. In this study, recombinant thioredoxin peroxidase-1 (SjTPx-1) and tandem repeat proteins (Sj1TR, Sj2TR, Sj4TR, Sj7TR) previously tested on human and water buffalo samples were used to assess its diagnostic applicability to dogs. Fifty-nine dog serum and stool samples were collected in the schistosomiasis-endemic municipalities of Calatrava, Negros Occidental and Catarman, Northern Samar in the Philippines and examined using the ELISA as compared to microscopy and fecal sample-based PCR. Samples positive for Babesia gibsoni and Dirofilaria immitis were also used to check for cross-reaction. Results showed that SjTPx-1 (80% sensitivity, 92.3% specificity) and Sj7TR (73.3% sensitivity, 92.3% specificity) have good potentials for diagnosing S. japonicum infection in dogs. These diagnostic antigens will therefore improve the surveillance in the transmission of the parasites from dogs to humans.


Assuntos
Ensaio de Imunoadsorção Enzimática/veterinária , Peroxirredoxinas/imunologia , Esquistossomose Japônica/diagnóstico , Animais , Antígenos de Helmintos , Cães , Ensaio de Imunoadsorção Enzimática/métodos , Filipinas/epidemiologia , Proteínas Recombinantes/imunologia , Schistosoma japonicum/imunologia
20.
Front Immunol ; 10: 1471, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31297120

RESUMO

Type 2 diabetes is a metabolic disorder characterized by persistently elevated glucose levels. There is no effective treatment strategy for this condition, and it poses a massive economic burden globally. Schistosoma soluble egg antigen (SEA)-induced immunomodulatory mechanisms have been reported in the treatment of autoimmune disease. This study aimed to determine the ability of Schistosoma japonicum SEA to protect against type 2 diabetes in Lepr db/db mice and understand the associated mechanisms. The mice were divided into four groups: C57BL/6 (the normal group), SEA (C57BL/6 mice treated with SEA), Lepr db/db , and SEA and Lepr db/db co-treatment groups. The mice in the SEA and co-treatment groups were injected with 50 µg of SEA (twice a week for 6 weeks), and the same volume of PBS was used as control. Blood glucose, insulin, and HOMA-IR levels were measured in all mice, which were sacrificed 6 weeks after the last SEA administration. Flow cytometry was used to detect the percentages of regulatory T cells in splenocytes. ELISA was used to detect the levels of IFN-γ, IL-2, IL-4, and IL-5 in cell culture supernatants. Compared with the mice in the Lepr db/db group, the mice in the SEA + Lepr db/db group exhibited significantly reduced insulin resistance, as evidenced by the enhancement of wound healing. The frequency of spleen regulatory T cells increased significantly after SEA administration; meanwhile, the secretion of IL-4 and IL-5 in spleen cells was elevated. These results indicate that SEA can reduce insulin resistance and provide new targets for the treatment of type 2 diabetes. The potential mechanisms might be associated with increases in regulatory T cells and Th2 cytokines in Lepr db/db mice, which warrants further investigation.


Assuntos
Antígenos de Helmintos , Citocinas/imunologia , Diabetes Mellitus Tipo 2/prevenção & controle , Óvulo/química , Schistosoma japonicum/química , Linfócitos T Reguladores/imunologia , Células Th2/imunologia , Animais , Antígenos de Helmintos/química , Antígenos de Helmintos/imunologia , Antígenos de Helmintos/farmacologia , Diabetes Mellitus Tipo 2/imunologia , Diabetes Mellitus Tipo 2/patologia , Camundongos , Óvulo/imunologia , Schistosoma japonicum/imunologia , Linfócitos T Reguladores/patologia , Células Th2/patologia
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