RESUMO
BACKGROUND: With decades of containment efforts, the prevalence of C. sinensis infection in Korea has shown a declining trend. However, well-tailored intervention assessments remain challenging, particularly when considering the potential impacts of cohort variations in raw freshwater fish consumption behavior, a major transmission route to humans, on this observed decline. METHODOLOGY: We applied an age-period-cohort modeling approach to nationally representative C. sinensis infection prevalence data from 1981-2012 in Korea to assess age, period, and cohort effects on its secular trend and to project the age-stratified prevalence up to 2023. PRINCIPAL FINDINGS: Our analysis suggests that both cohort and period effects have substantially contributed to the declining prevalence of C. sinensis infection in Korea. Age-stratified projections up to 2023 suggest a decline in prevalence across all age groups, while those aged over 40 are anticipated to maintain prevalences above the elimination threshold of 1%. CONCLUSIONS: Our study highlights the importance of incorporating cohort effects into intervention assessments aimed at controlling C. sinensis infection. The effectiveness of interventions remains evident in Korea despite adjusting for the cohort effect. This approach, applicable to other endemic countries, would provide valuable insights for intervention assessments and inform future public health planning to eliminate C. sinensis infection.
Assuntos
Clonorquíase , Clonorchis sinensis , República da Coreia/epidemiologia , Clonorquíase/epidemiologia , Humanos , Animais , Prevalência , Adulto , Pessoa de Meia-Idade , Adulto Jovem , Idoso , Adolescente , Criança , Fatores Etários , Pré-Escolar , Masculino , Feminino , Idoso de 80 Anos ou mais , Lactente , Estudos de CoortesRESUMO
We developed a new concentration kit, called the ParaEgg (PE), for easy detection trematode eggs from fecal samples in endemic areas of clonorchiasis and metagonimiasis in Korea. To create a standard of detection efficiency, 120 fecal samples were examined using the water-ether concentration method (WECM). The PE kit and Mini ParaSep (PS) kit were used to compare the detection sensitivity of 100 egg-positive and 20 egg-negative samples in WECM. Additionally, stool samples, which were intentionally spiked with 10, 20, and 30 Clonorchis sinensis eggs, were evaluated to assess the sensitivity in lowinfection cases. The PE and PS kits showed detection rates of 100% and 92%, respectively, from 100 egg-positive samples in WECM. Meanwhile, eggs were detected in 3 (PE) and 2 (PS) out of 20 egg-negative samples in WECM. The PE kit detected the highest number of eggs per gram of feces (727 on average), followed by the WECM (524) and PS kit (432). In fecal samples that were intentionally spiked with 10, 20, and 30 C. sinensis eggs, PE only detected eggs 2 out of 5 samples in 10 eggs spiked (40%), and the detection rates were 80% and 100%, respectively. The PE kit enabled a more accurate identification of trematode eggs because of the clearance of small fecal debris in the microscopic field. In conclusion, the PE kit is obviously helpful to detect and identify trematode eggs in stool examinations especially in endemic areas of clonorchiasis and metagonimiasis.
Assuntos
Fezes , Contagem de Ovos de Parasitas , Sensibilidade e Especificidade , Fezes/parasitologia , Animais , Contagem de Ovos de Parasitas/métodos , Humanos , Kit de Reagentes para Diagnóstico/normas , República da Coreia , Clonorchis sinensis/isolamento & purificação , Clonorquíase/diagnóstico , Clonorquíase/parasitologia , Óvulo , Infecções por Trematódeos/diagnóstico , Infecções por Trematódeos/parasitologiaRESUMO
Blastocystis sp. is the most common intestinal protozoan affecting human health worldwide. Several studies have reported the prevalence of Blastocystis sp. in various regions of the Republic of Korea. However, limited data are available on the prevalence and subtype (ST) distribution of this parasite among regions. Therefore, we investigated the prevalence and ST distributions of this parasite in the Republic of Korea. For this purpose, 894 stool specimens were collected from patients with diarrhea and tested for the presence of Blastocystis sp. using PCR analysis. The isolates were subsequently subtyped. The overall prevalence was 11.6%. Of the 104 isolates, ST3 was the most prevalent, followed by ST1. Additionally, a single case of the rare subtype ST8 was identified, representing the first reported case in the Republic of Korea. The results suggested that the predominance of ST3 observed in this study reflects human-to-human transmission with low genetic diversity within the ST, while ST1 transmission is likely correlated with animals. In the future, to better understand Blastocystis sp. transmission dynamics, human, animal, and environmental factors should be studied from a "One Health" perspective.
RESUMO
This study aimed to evaluate the positive rates for Enterobius vermicularis eggs among preschool children in Yeosu-si, Jeollanam-do, the Republic of Korea (Korea) over a period of 5 years (2017-2021). Perianal swab samples, obtained using cellotape, from 10,392 preschool children in 26 districts were examined microscopically for E. vermicularis eggs. The test results were notified through the local health center, and the families of children who tested positive were advised to provide them anthelmintics treatment. The annual positive rates were 5.0%, 5.2%, 4.4%, 2.2%, and 1.0% in 2017, 2018, 2019, 2020, and 2021, respectively. The overall positive rate was higher in boys than in girls (P< 0.05), and children aged 5-7 years were at a higher risk of being infected than those aged 0-4 years (P< 0.05). Although the rates of infection by E. vermicularis in the survey area, Yeosu-si, were still in the 1% range , the results of this study suggest that they can be significantly reduced through continuous intervention centered around the test-treatment strategy.
Assuntos
Enterobíase , Enterobius , Animais , Feminino , Masculino , Humanos , Pré-Escolar , Enterobíase/diagnóstico , Prevalência , Coreia (Geográfico) , República da Coreia/epidemiologiaRESUMO
Inflammatory bowel disease (IBD) is a chronic and recurrent illness of the gastrointestinal tract. Treatment of IBD traditionally involves the use of aminosalicylic acid and steroids, while these drugs has been associated with untoward effects and refractoriness. The absence of effective treatment regimen against IBD has led to the exploration of new targets. Parasites are promising as an alternative therapy for IBD. Recent studies have highlighted the use of parasite-derived substances, such as excretory secretory products, extracellular vesicles (EVs), and exosomes, for the treatment of IBD. In this report, we examined whether EVs secreted by Giardia lamblia could prevent colitis in a mouse model. G. lamblia EVs (GlEVs) were prepared from in vitro cultures of Giardia trophozoites. Clinical signs, microscopic colon tissue inflammation, and cytokine expression levels were detected to assess the effect of GlEV treatment on dextran sulfate sodium (DSS)-induced experimental murine colitis. The administration of GlEVs prior to DSS challenge reduced the expression levels of pro-inflammatory cytokines, including tumor necrosis factor alpha, interleukin 1 beta, and interferon gamma. Our results indicate that GlEV can exert preventive effects and possess therapeutic properties against DSS-induced colitis.
Assuntos
Colite , Vesículas Extracelulares , Giardia lamblia , Doenças Inflamatórias Intestinais , Camundongos , Animais , Sulfato de Dextrana/efeitos adversos , Sulfato de Dextrana/metabolismo , Camundongos Endogâmicos C57BL , Giardia lamblia/metabolismo , Colite/induzido quimicamente , Colite/metabolismo , Colite/patologia , Doenças Inflamatórias Intestinais/metabolismo , Doenças Inflamatórias Intestinais/patologia , Citocinas/metabolismo , Vesículas Extracelulares/metabolismo , Vesículas Extracelulares/patologia , Modelos Animais de Doenças , Colo/patologiaRESUMO
The positive rate of Clonorchis sinensis is the highest among intestinal parasites in the Republic of Korea (Korea). More than 1.2 million people were at risk of C. sinensis infection in Korea in 2012. An intensive control program is being implemented for residents of the 5 major river basins to reduce helminthic infections, including C. sinensis infection. This study evaluated the continuous intensive control program for parasitic diseases including clonorchiasis in areas near the 5 major river basins in Korea over the past 10 years (2011-2020). A total of 335,020 fecal samples (one sample per resident) prepared by the modified sedimentation technic were microscopically examined. Those who expelled helminth eggs were treated with anthelmintics through local health centers and re-examined 3 months later. The overall positive rate of helminths egg was 7.1%. The annual positive rates were dramatically decreased from 14.4% (2011) to 5.9% (2020). The egg positive rate was highest in C. sinensis (5.3%), followed by heterophyid flukes (1.5%) and Trichuris trichiura (0.2%). The prevalence of C. sinensis was significantly higher in males (7.6%) than in females (3.7%), and the highest in the 50-59 years (7.0%) age group. Our results are beneficial to establish prevention and control policies against helminthiases including clonorchiasis in endemic areas in this country.
Assuntos
Clonorquíase/epidemiologia , Clonorchis sinensis , Helmintíase/epidemiologia , Fatores Etários , Animais , Anti-Helmínticos/uso terapêutico , Clonorquíase/tratamento farmacológico , Clonorquíase/parasitologia , Clonorquíase/prevenção & controle , Clonorchis sinensis/isolamento & purificação , Fezes/parasitologia , Feminino , Helmintíase/tratamento farmacológico , Helmintíase/prevenção & controle , Helmintos/isolamento & purificação , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , República da Coreia/epidemiologia , Rios , Fatores SexuaisRESUMO
The endemicity of zoonotic trematode metacercariae (ZTM) was investigated with total 871 freshwater fishes (19 species) from Deokcheon-gang (a branch stream of Gyeongho-gang) in Sancheong-gun, Gyeongsangnam-do, Korea for 3 years (2018-2020). All fishes were examined with the artificial digestion method. The metacercariae of Clonorchis sinensis (CsMc) were detected in 233 (36.3%) out of 642 fish in 11 positive fish species (PFS), and their infection intensity was 27 per fish infected (PFI). Especially, in index fish, Puntungia herzi, of CsMc infection, prevalence was 64.2% and infection intensity was 37 PFI. Metagonimus spp. metacercariae (MsMc) were found in 760 (87.5%) out of 869 fish in 18 PFS and their infection intensity was 228 PFI. In sweet smelt, Plecoglossus altivelis, the prevalence of MsMc was 97.6% and their infection intensity was 3,570 PFI. Centrocestus armatus metacercariae were detected in 209 (29.4%) out of 710 fish in 8 PFS and their infection intensity was 1,361 PFI. Echinostoma spp. metacercariae were found in 293 (42.6%) out of 688 fish in 15 PFS and their infection intensity was 5 PFI. Metacercariae of Clinostomum complanatum and Metorchis orientalis were also detected in 2.7% and 21.2% fish in 4 PFS and their infection intensities were 3.1 and 3.4 PFI respectively. By the present study, it was confirmed that some species of ZTM including CsMc and MsMc are more or less prevalent in fishes from Deokcheon-gang in Sancheong-gun, Gyeongsangnam-do, Korea.
Assuntos
Doenças dos Peixes , Peixes/parasitologia , Trematódeos , Animais , Doenças dos Peixes/epidemiologia , Doenças dos Peixes/parasitologia , Metacercárias , República da Coreia/epidemiologia , RiosRESUMO
The infection status of zoonotic trematode metacercariae (ZTM) was investigated in total 568 freshwater fishes (19 species) from the irrigation canal of Togyo-jeosuji (Reservoir) in Cheorwon-gun, Gangwon-do, the Republic of Korea for 3 years (2018-2020). All fishes were examined using the artificial digestion method. The metacercariae of Clonorchis sinensis (CsMc) were detected in 180 (43.8%) out of 411 fish of positive species, and their infection intensity was 38 per fish infected (PFI). Especially, in 2 fish species, i.e., Pseudorasbora parva and Puntungia herzi, the prevalence was 82.1% and 31.3%, and the infection intensity with CsMc was 88 and 290 PFI, respectively. Metagonimus spp. metacercariae (MsMc) were found in 403 (74.1%) out of 544 fish of positive species, and their infection intensity was 62 PFI. In the pale chub, Zacco platypus, the prevalence of MsMc was 98.6%, and their infection intensity was 144 PFI. Centrocestus armatus metacercariae were detected in 171 (38.9%) out of 440 fish of positive species, and their infection intensity was 1,844 PFI. Echinostoma spp. metacercariae were found in 94 (19.6%) out of 479 fish of positive species, and their infection intensity was 3 PFI. Metorchis orientalis metacercariae were detected in 43 (29.3%) out of 147 fish of positive species, and their infection intensity was 4 PFI. By the present study, it has been confirmed that some species of ZTM, including CsMc and MsMc, are prevalent in fishes from the irrigation canal of Togyo-jeosuji in Cheorwon-gun, Gangwon-do, Korea.
Assuntos
Doenças dos Peixes , Trematódeos , Infecções por Trematódeos , Animais , Doenças dos Peixes/epidemiologia , Peixes , Metacercárias , República da Coreia/epidemiologia , Infecções por Trematódeos/epidemiologia , Infecções por Trematódeos/veterináriaRESUMO
The infection status with Clonorchis sinensis metacercariae (CsMc) was examined in freshwater fishes from Yongjeon-cheon (a branch of Nakdong-gang) located in Cheongsong-gun, Gyeongsangbuk-do, the Republic of Korea (Korea). A total of 750 fishes in 19 species were examined by the artificial digestion method for 2 years (2019 and 2020). CsMc were detected in 378 (51.4%) out of 735 fishes in 14 species (73.7%), and the infection intensity was 666 per fish infected. In 2019, CsMc were found in 172 (68.0%) out of 253 fishes in 10 species, and the infection intensity was 565 per fish infected. In 2020, CsMc were detected in 206 (62.2%) out of 331 fishes in 10 species, and the infection intensity was 751 per fish infected. The other zoonotic trematode, ie. Metagonimus spp., Centrocestus armatus, Echinostoma spp. and Clinostomum complanatum, metacercariae were also detected in fishes from the survey streams, but their endemicities were relatively low. Conclusively, it was first confirmed that CsMc are highly endemic in fishes from Yongjeon-cheon in Cheongsong-gun, Gyeongsangbuk-do, Korea.
Assuntos
Clonorquíase/epidemiologia , Clonorquíase/veterinária , Clonorchis sinensis/isolamento & purificação , Doenças dos Peixes/epidemiologia , Doenças dos Peixes/parasitologia , Peixes/parasitologia , Animais , Clonorquíase/parasitologia , Água Doce , República da Coreia/epidemiologiaRESUMO
Cyclospora cayetanensis is an apicomplexan protozoan and is one of the most common pathogens causing chronic diarrhea worldwide. Eight stool samples with diarrheal symptom out of 18 Korean residents who traveled to Nepal were obtained, and examined for 25 enteropathogens including 16 bacterial species, 5 viral species, and 4 protozoans in stool samples as causative agents of water-borne and food-borne disease. Only C. cayetanensis was detected by nested PCR, and 3 PCR-positive samples were sequenced to confirm species identification. However, the oocysts of C. cayetanensis in fecal samples could not be detected by direct microscopy of the stained sample. As far as we know, this is the first report of a group infection with C. cayetanensis from a traveler visiting Nepal, and the second report of a traveler's diarrhea by C. cayetanensis imported in Korea.
Assuntos
Cyclospora/isolamento & purificação , Ciclosporíase/epidemiologia , Ciclosporíase/parasitologia , Surtos de Doenças , Doenças Transmitidas por Alimentos/parasitologia , Viagem , Cyclospora/genética , Ciclosporíase/complicações , Diarreia/etiologia , Diarreia/parasitologia , Fezes/parasitologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nepal , Reação em Cadeia da Polimerase , República da CoreiaRESUMO
Inflammatory bowel disease (IBD) is an inflammatory disease caused by the activity of effector immune cells, such as the overproduction of inflammatory cytokines. Helminth immunomodulation in the host has been shown to have therapeutic implications in IBD. In the present study, we investigated whether Metagonimus miyatai infection could ameliorate inflammatory diseases. Mice were infected with M. miyatai, and colitis was then induced through oral administration of dextran sulfate sodium (DSS). Weight loss, stool consistency, gross bleeding, colon length, and tissue inflammation were assessed by macroscopic and microscopic examinations. In addition, regulatory cytokine expression was observed in colon tissue by reverse transcription polymerase chain reaction. The results showed that M. miyatai infection decreased the clinical severity of DSS-induced colitis, including weight loss, bloody diarrhea, shortening of the colon, and colon tissue damage in mice (pâ¯<â¯.05). The expression levels of tumor necrosis factor-α, interleukin-1b, and cyclooxygenase-2 in mice infected with helminth were lower than those in DSS-treated mice without helminthic infection (pâ¯<â¯.05). The results of the research showed that pre-infection with M. miyatai ameliorated DSS-induced colitis in mice and may be a novel therapeutic strategy for the treatment of immunological diseases.
Assuntos
Colite/induzido quimicamente , Colite/prevenção & controle , Heterophyidae , Imunomodulação , Animais , Colo/imunologia , Colo/parasitologia , Citocinas/imunologia , Sulfato de Dextrana , Modelos Animais de Doenças , Feminino , Camundongos , Camundongos Endogâmicos C57BLRESUMO
Clonorchis sinensis is the most common fish-borne intestinal parasite in Korea. The aim of the present investigation was to survey the status of C. sinensis infection and analyze associated risk factors in residents of Haman-gun, Gyeongsangnam-do. A total of 5,114 residents from 10 administrative towns/villages voluntarily agreed to participate in the study, which comprised fecal examination, a questionnaire survey for risk factors, ultrasonography, and enzymelinked immunosorbent assay for cancer biomarker detection in the blood. We detected C. sinensis eggs in 5.3% of the subjects. By region, Gunbuk-myeon had the highest number of residents with C. sinensis eggs. The infection rate and intensity were higher in male than in female residents. Based on the risk factor questionnaire, infection was highly associated with drinking, a history of C. sinensis infection, and the practice of eating of raw freshwater fish. Extension of the bile duct, infection intensity, and cancer biomarker detection significantly correlated with the presence of eggs in the study population. In conclusion, the development of feasible, long-term control policies and strategies for the elimination of C. sinensis in Korea is still required.
Assuntos
Clonorquíase/epidemiologia , Clonorquíase/parasitologia , Clonorchis sinensis , Comportamento Alimentar/fisiologia , Peixes/parasitologia , Adulto , Idoso , Animais , Estudos de Casos e Controles , Clonorquíase/prevenção & controle , Fezes/parasitologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Contagem de Ovos de Parasitas , República da Coreia/epidemiologia , Fatores de Risco , Fatores Sexuais , Inquéritos e QuestionáriosRESUMO
Cryptosporidium parvum and Giardia duodenalis are the main diarrhea-causing parasitic pathogens; however, their prevalence in Korea is unknown. Here, we conducted a survey to determine the prevalence and genotype distribution of these 2 pathogens causing acute diarrhea in 8,571 patients hospitalized in 17 Regional Institute of Health Environment sites in Korea, during 2013-2016. C. parvum and G. duodenalis were detected and genotyped by nested PCR, and the isolate were molecularly characterized by sequencing the glycoprotein 60 (Gp60) and ß-giardin genes, respectively. The overall prevalence of C. parvum and G. duodenalis was 0.37% (n=32) and 0.55% (n=47), respectively, and both pathogens were more prevalent in children under 9 years old. Molecular epidemiological analysis showed that the C. parvum isolates belonged to the IIa family and were subtyped as IIaA13G2R1, IIaA14G2R1, IIaA15G2R1, and IIaA18G3R1. Analysis of the ß-giardin gene fragment from G. duodenalis showed that all positive strains belong to assemblage A. This is the first report on the molecular epidemiology and subtyping of C. parvum and G. duodenalis in such a large number of diarrheal patients in Korea. These results highlight the need for continuous monitoring of these zoonotic pathogens and provide a basis for implementing control and prevention strategies. Further, the results might be useful for epidemiological investigation of the source of outbreak.
Assuntos
Criptosporidiose/parasitologia , Cryptosporidium parvum/isolamento & purificação , Diarreia/parasitologia , Giardia lamblia/isolamento & purificação , Giardíase/parasitologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Criança , Pré-Escolar , Criptosporidiose/diagnóstico , Criptosporidiose/epidemiologia , Cryptosporidium parvum/classificação , Cryptosporidium parvum/genética , Diarreia/diagnóstico , Diarreia/epidemiologia , Fezes/parasitologia , Feminino , Genótipo , Giardia lamblia/classificação , Giardia lamblia/genética , Giardíase/diagnóstico , Giardíase/epidemiologia , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Filogenia , República da Coreia/epidemiologia , Adulto JovemRESUMO
Opisthorchis viverrini, a parasitic trematode, was recategorized as a group 1 biological carcinogen because it causes opisthorchiasis, which may result in cholangiocarcinoma. A new strategy for controlling opisthorchiasis is needed because of issues such as drug resistance and reinfection. Triosephosphate isomerase (TIM), a key enzyme in energy metabolism, is regarded as a potential drug target and vaccine candidate against various pathogens. Here, we determined the crystal structures of wild-type and 3 variants of TIMs from O. viverrini (OvTIM) at high resolution. The unique tripeptide of parasite trematodes, the SAD motif, was located on the surface of OvTIM and contributed to forming a 310-helix of the following loop in a sequence-independent manner. Through thermal stability and structural analyses of OvTIM variants, we found that the SAD motif induced local structural alterations of the surface and was involved in the overall stability of OvTIM in a complementary manner with another parasite-specific residue, N115. Comparison of the surface characteristics between OvTIM and Homo sapiens TIM (HsTIM) and structure-based epitope prediction suggested that the SAD motif functions as an epitope.
Assuntos
Epitopos/química , Opisthorchis/enzimologia , Triose-Fosfato Isomerase/química , Motivos de Aminoácidos , Sequência de Aminoácidos , Animais , Estabilidade Enzimática , Humanos , Modelos Moleculares , TemperaturaRESUMO
INTRODUCTION: Clonorchis sinensis is a major parasite affecting the Korea population. Despite the high infection rate and pathogenicity, very few studies have been conducted to investigate the immune responses against the proteins of C. sinensis. METHODS: In this study, in vitro immune response induced by a recombinant 21.6 kDa tegumental protein derived from C. sinensis (rCsTegu21.6) was confirmed in murine dendritic cells and T cells. For the in vivo analysis, each mouse was immunized three times. Total serum IgG and T cell cytokine production were determined by ELISA, while T cell proliferation was detected by a WST (Water-Soluble Tetrazolium salt)-1 assay. RESULTS: In vitro tests indicated that rCsTegu21.6 treatment increased the expression of surface molecules, such as CD40 (77%), CD80 (52%) and CD86 (46%), on murine dendritic cells and the secretion of cytokines (TNF-α, IL-6, IL-1ß, IL-10, and IL-12p70). Moreover, co-culturing dendritic cells activated by rCsTegu21.6 with allogenic T cells induced T cell proliferation over time. rCsTegu21.6 also stimulated specific antibody production and cytokine secretion [IL-2, IL-4, and interferon (IFN)-γ)] from T cells following immunization in vivo. Notably, rCsTegu21.6 predominantly induced IgG1 production and secretion of the Th2 cytokine IL-4, regardless of the type of adjuvant used. CONCLUSION: These results serve as a foundation for the development of tegumental protein-based vaccines against C. sinensis.
Assuntos
Clonorquíase/imunologia , Clonorchis sinensis/química , Proteínas de Helminto/imunologia , Células Th1/imunologia , Células Th2/imunologia , Animais , Anticorpos Anti-Helmínticos/sangue , Citocinas/sangue , Células Dendríticas/imunologia , Imunidade Celular , Imunoglobulina G/sangue , Interferon gama/genética , Interleucina-4/genética , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos BALB C , Proteínas Recombinantes/imunologiaRESUMO
Venom allergen-like (VAL) proteins are important to host-parasite interactions. We previously demonstrated that a Clonorchis sinensis VAL (CsVAL) protein-derived synthetic peptide suppresses allergic and inflammatory responses. However, little is known regarding the physicochemical and antigenic properties of CsVAL proteins. Here, we identified a novel 194 amino acid VAL protein, named C. sinensis VAL 28 (CsVAL28), and characterized its functional motifs and structural details as a new member of the CAP superfamily. Unlike members of the Schistosoma mansoni VAL (SmVAL) family, CsVAL28 has a single CAP1 motif and six highly conserved disulfide bond-forming cysteines. Tertiary models of wild-type CsVAL28 and mutants were built using SmVAL4 as template via homology modeling. Normal mode analysis predicted that disulfide bond breaking by mutation of cysteine 124 to serine would greatly affect protein mobility. Four major immunoreactive linear epitopes were identified in the surface-exposed region or its vicinity via epitope mapping, using sera from clonorchiasis patients and healthy controls. Our findings provide in-depth knowledge on the structure-function properties of VAL proteins and may help determine highly antigenic regions for developing new diagnostic approaches.
Assuntos
Antígenos de Helmintos/isolamento & purificação , Clonorchis sinensis/química , Proteínas de Helminto/isolamento & purificação , Adulto , Alérgenos/química , Sequência de Aminoácidos , Animais , Antígenos de Helmintos/química , Antígenos de Helmintos/imunologia , Clonorquíase/imunologia , Clonorquíase/parasitologia , Clonorchis sinensis/imunologia , Cisteína/química , Mapeamento de Epitopos , Epitopos/análise , Proteínas de Helminto/química , Proteínas de Helminto/imunologia , Humanos , Modelos Moleculares , Conformação Proteica , Peçonhas/químicaRESUMO
To investigate the prevalence of intestinal parasite infections in Yanbian Prefecture, Jilin Province, China, epidemiological surveys were conducted on a collaboration basis between the Korean Centers for Disease Control and Prevention and the Yanbian Center for Disease Control and Prevention. A total of 8,396 (males 3,737 and females 4,659) stool samples were collected from 8 localities and examined with the formalin-ether sedimentation technique, and additionally examined with the cellotape anal swab to detect Enterobius vermicularis eggs. The overall rate of intestinal parasites was 1.57%. The prevalence of Ascaris lumbricoides was the highest (0.80%), followed by Entamoeba spp. (0.23%), heterophyid flukes (0.15%), Clonorchis sinensis (0.08%), Enterobius vermicularis (0.07%), hookworms (0.06%), Trichostrongylus spp. (0.06%), Giardia lamblia (0.04%), Paragonimus spp. (0.02%), Diphyllobothrium spp. (0.02%), Trichuris trichiura (0.02%). The prevalence by sex was similar, 1.58% (n=59) in males and 1.57% (n=73) in females. By the present study, it is partly revealed that the prevalences of intestinal parasite infections are relatively low among the inhabitants of Yanbian Prefecture, Jilin Province, China.
Assuntos
Enteropatias Parasitárias/epidemiologia , Enteropatias Parasitárias/parasitologia , Animais , Ascaris lumbricoides/isolamento & purificação , China/epidemiologia , Enterobius/isolamento & purificação , Fezes/parasitologia , Feminino , Humanos , Masculino , Prevalência , Trematódeos/isolamento & purificaçãoRESUMO
This study was conducted to evaluate the infection rates of Clonorchis sinensis and laboratory findings in infected people. The 3,167 fecal samples, from nine villages in Okcheon-gun, were examined.
RESUMO
Survival of Clonorchis sinensis, a cause of human clonorchiasis, requires tegument proteins, which are localized to the tegumental outer surface membrane. These proteins play an important role in a host response and parasite survival. Thus, these proteins are interesting molecular targets for vaccine and drug development. Here, we have determined two crystal structures of the calmodulin like domain (amino acid [aa] positions 1-81) and dynein light chain (DLC)-like domain (aa 83-177) of a 20.8-kDa tegumental-allergen-like protein from Clonorchis sinensis (CsTAL3). The calmodulin like domain has two Ca2+-binding sites (named CB1 and CB2), but Ca2+ binds to only one site, CB1. The DLC-like domain has a dimeric conformation; the interface is formed mainly by hydrogen bonds between the main chain atoms. In addition, we have determined full-length structure of CsTAL3 in solution and showed the conformational change of CsTAL3 induced by Ca2+ ion binding using small-angle X-ray scattering analysis and molecular dynamics simulations. The Ca2+-bound form has a more extended conformation than the Ca2+-free from does. These structural and biochemical analyses will advance the understanding of the biology of this liver fluke and may contribute to our understanding of the molecular mechanism of calcium-responsive and tegumental-allergen-like proteins.
Assuntos
Alérgenos/química , Clonorchis sinensis/química , Proteínas de Helminto/química , Sequência de Aminoácidos , Animais , Modelos Moleculares , Peso Molecular , Domínios Proteicos , Multimerização Proteica , Espalhamento a Baixo Ângulo , Alinhamento de Sequência , Soluções , Difração de Raios XRESUMO
BACKGROUND: Heat shock proteins (HSPs) are found in all prokaryotes and most compartments of eukaryotic cells. Members of the HSP family mediate immune responses to tissue damage or cellular stress. However, little is known about the immune response induced by the oriental liver fluke, Clonorchis sinensis, even though this organism is carcinogenic to humans. We address this issue in the present study in mouse bone marrow dendritic cells (mBMDCs), using recombinant HSP70 and 90 from C. sinensis (rCsHSP70 and rCsHSP90). METHODS: rCsHSP70 and rCsHSP90 were produced in an E. coli system. Purified recombinant proteins were treated in BMDCs isolated from C57BL/6 mice. T cells were isolated from Balb/c mice and co-cultured with activated mBMDCs. Expression of surface molecules was measured by flow cytometry and cytokine secretion was quantified using ELISA. C57BL/6 mice were divided into four groups, including peptide alone, peptide/Freund's adjuvant, peptide/CsHSP70, peptide/CsHSP90, and were immunized intraperitoneally three times. Two weeks after final immunization, antibodies against peptide were measured using ELISA. RESULTS: Both proteins induced a dose-dependent upregulation in major histocompatibility complex and co-stimulatory molecule expression and increased secretion of pro-inflammatory cytokines including interleukin (IL)-1ß, -6, and -12p70 and tumor necrosis factor-α in mBMDCs. Furthermore, when allogenic T cells were incubated with mBMDCs activated by rCsHSP70 and rCsHSP90, the helper T cell (Th)1 cytokine interferon-γ was up-regulated whereas the level of the Th2 cytokine IL-4 was unchanged. These results indicate that rCsHSPs predominantly induce a Th1 response. Over and above these results, we also demonstrated that the production of peptide-specific antibodies can be activated after immunization via in vitro peptide binding with rCsHSP70 or rCsHSP90. CONCLUSION: This study showed for the first time that the HSP or HSP/peptide complexes of C. sinensis could be considered as a more effective vaccine against C. sinensis infection as results of the activator of host immune response as well as the adjuvant for antigenic peptide conjugate to induce peptide-specific antibody response in mice.