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1.
Medicine (Baltimore) ; 100(4): e24456, 2021 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-33530255

RESUMO

RATIONALE: Severe laryngeal edema can cause upper airway obstruction, which is fatal. Pseudoterranova, an uncommon nematode of the family Anisakidae, predominantly invades the stomach after ingestion of the nematodes in raw or undercooked marine fish. There have been a few reports of development of severe laryngeal edema caused by the nematode invading the base of the tongue. PATIENT CONCERNS: A 69-year-old Japanese woman complained of stuffy and scratchy throat for 8 hours and reported eating sashimi, fresh slices of raw jacopever, 4 days before the first visit. DIAGNOSIS: Endoscopy revealed a white-yellowish wriggling worm at the left side of the base of the tongue and severe edema of the larynx. INTERVENTIONS: The worm was extracted using endoscopic forceps. The patient was hospitalized and treated with intravenous injection of an antibiotic and steroid. OUTCOMES: The symptoms and laryngeal edema disappeared the next day. The worm was identified as a 4th-stage larva of Pseudoterranova spp based on morphologic features. The serum Anisakis-specific IgE antibody level was high, at 38.6 UA/mL. LESSONS: Clinicians should be aware of the possibility of severe laryngeal edema due to invasion by anisakid nematodes in the pharyngolaryngeal area in cases involving previous ingestion of raw or uncooked marine fish.


Assuntos
Anisaquíase/complicações , Edema Laríngeo/etiologia , Idoso , Animais , Anisakis/isolamento & purificação , Anticorpos Anti-Helmínticos/sangue , Feminino , Peixes , Humanos , Larva
2.
PLoS Negl Trop Dis ; 14(12): e0008998, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33370333

RESUMO

Clonorchiasis caused by Clonorchis sinensis is endemic in East Asia; approximately 15 million people have been infected thus far. To diagnose the infection, serodiagnostic tests with excellent functionality should be performed. First, 607 expressed sequence tags encoding polypeptides with a secretory signal were expressed into recombinant proteins using an in vitro translation system. By protein array-based screening using C. sinensis-infected sera, 18 antigen candidate proteins were selected and assayed for cross-reactivity against Opisthorchis viverrini-infected sera. Of the six antigenic proteins selected, four were synthesized on large scale in vitro and evaluated for antigenicity against the flukes-infected human sera using ELISA. CsAg17 antigen showed the highest sensitivity (77.1%) and specificity (71.2%). The sensitivity and specificity of the bacterially produced CsAg17-28GST fusion antigen was similar to those of CsAg17 antigen. CsAg17 antigen can be used to develop point-of-care serodiagnostic tests for clonorchiasis.


Assuntos
Anticorpos Anti-Helmínticos/sangue , Antígenos de Helmintos/imunologia , Clonorquíase/diagnóstico , Clonorchis sinensis/imunologia , Animais , Clonorchis sinensis/genética , Reações Cruzadas/imunologia , Ensaio de Imunoadsorção Enzimática , Peixes/parasitologia , Humanos , Imunoglobulina G/sangue , Opisthorchis/imunologia , Testes Imediatos , Proteogenômica , Alimentos Crus/parasitologia , Sensibilidade e Especificidade , Testes Sorológicos
3.
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi ; 32(6): 598-604, 2020 Nov 20.
Artigo em Chinês | MEDLINE | ID: mdl-33325194

RESUMO

OBJECTIVE: To evaluate the effect of the integrated echinococcosis control program in Ningxia Hui Autonomous Region from 2011 to 2018. METHODS: A package of integrated interventions were employed for echinococcosis control in 22 counties (districts) of Ningxia Hui Autonomous Region from 2011 to 2018, including screening of human echinococcosis, treatment of echinococcosis patients, deworming of domestic dogs and monitoring of infections, surveillance of echinococcosis in bovines and sheep, health education. The detection of human echinococcosis, seroprevalence of anti-Echinococcus antibody in children at ages of 6 to 12 years, the Echinococcus coproantigen-positive rate in domestic dogs, prevalence of echinococcosis in bovines and sheep, and the awareness of echinococcosis control knowledge were investigated and compared during the period between 2011 and 2018. RESULTS: The detection of human echinococcosis appeared a decline tendency in Ningxia Hui Autonomous Region over years during the period from 2011 to 2018 (χ2trend = 82.22, P < 0.05), and the prevalence of human echinococcosis decreased from 0.31% in 2011 to 0.15% in 2018. The seroprevalence of anti-Echinococcus antibody appeared a decline tendency in children at ages of 6 to 12 years over years (χ2trend = 439.64, P < 0.01), and the prevalence of anti-Echinococcus antibody decreased from 6.12% in 2011 to 0.67% in 2018. The Echinococcus coproantigen-positive rate appeared a decline tendency in domestic dogs over years (χ2trend = 260.33, P < 0.05), and the prevalence of anti-Echinococcus antibody decreased from 7.11% in 2011 to 0.75% in 2018. The prevalence of bovine and sheep echinococcosis reduced from 3.26% and 5.08% in 2011 to 1.35% and 0.76% in 2018, and Echinococcus predominantly parasitized in bovine (92.00%) and sheep (93.94%) livers. A total of 63 stool samples were collected from red fox, wolf and badger in Xiji and Haiyuan counties of Ningxia Hui Autonomous Region in 2013 and 2014, with no Echinococcus coproantigen-positives detected, and 107 domestic cats and 3 domestic dogs were dissected in these two counties, with no Echinococcus found. A total of 6 046 wild mice were dissected in Xiji County, Yuanzhou District and Haiyuan County of Ningxia Hui Autonomous Region from 2016 to 2019, and the prevalence of E. multilocularis was 0.31%. The awareness of echinococcosis control knowledge appeared an increasing tendency in Ningxia Hui Autonomous Region over years from 2011 to 2018 (χ2trend = 3 367.97, P < 0.01), and the awareness increased from 21.83% in 2011 to 72.24% in 2018. CONCLUSIONS: The integrated echinococcosis control program achieves a remarkable effect in Ningxia Hui Autonomous Region, and the transmission of echinococcosis has been preliminarily controlled. However, the echinococcosis transmission risk remains in few regions, and the integrated echinococcosis control program remains to be reinforced.


Assuntos
Equinococose , Animais , Anticorpos Anti-Helmínticos/sangue , Gatos , Bovinos , China/epidemiologia , Cães , Equinococose/epidemiologia , Equinococose/prevenção & controle , Equinococose/veterinária , Echinococcus , Humanos , Camundongos , Prevalência , Estudos Soroepidemiológicos , Ovinos
4.
Parasitol Res ; 119(11): 3691-3698, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33009945

RESUMO

Fascioliasis, a food- and water-borne trematodiasis, has been identified as a public health threat by the World Health Organization, with millions of people estimated to be infected or at risk of infection worldwide. We developed an immunochromatographic test (ICT) as a point-of-care (POC) tool for the rapid serodiagnosis of human fascioliasis caused by Fasciola gigantica and evaluated their diagnostic ability. Two tests were developed using antigens from adult F. gigantica excretory-secretory (ES) product and recombinant F. gigantica cathepsin L (rFgCL). Sera from 12 patients with parasitologically proven fascioliasis caused by F. gigantica, 18 with clinically suspected fascioliasis, 65 with other parasitic infections, and 30 healthy controls were used. Using a cutoff of > 0.5 for antibody detection, the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of the ES-based ICT method were 100%, 98.9% 96.8%, 100%, and 99.2%, respectively, and those of the rFgCL-based ICT method were 86.7%, 93.7%, 81.3%, 95.7%, and 92.0%, respectively. The concordance between the two methods was 91.2%. Tests using F. gigantica ES and rFgCL antigens can be employed quickly and easily as POC diagnostic tools. They can be used to support the clinical diagnosis of human fascioliasis gigantica and in large-scale surveys in endemic areas throughout tropical regions without necessitating additional facilities or ancillary supplies.


Assuntos
Antígenos de Helmintos/imunologia , Catepsina L/imunologia , Fasciola/isolamento & purificação , Fasciolíase/diagnóstico , Animais , Anticorpos Anti-Helmínticos/sangue , Catepsina F/sangue , Cromatografia de Afinidade , Fasciola/imunologia , Humanos , Testes Imediatos , Sensibilidade e Especificidade , Testes Sorológicos/métodos
5.
Exp Parasitol ; 218: 107997, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32946882

RESUMO

Toxocara cati is one of the causative agents of human toxocariasis. Serological methods are used for diagnosis in paratenic hosts like humans but the humoral immune response triggered by this parasite is unknown. We characterized the humoral immune response to T. cati excretory-secretory antigens (TES) in pigs as animal model during the acute and chronic stages of infection. ELISA and Western Blot techniques were used to determine antibody response. Pigs were experimentally inoculated with 100,000 infective Toxocara cati eggs. Blood was collected at 7, 14, 21 and 28 days post-inoculation (d.p.i.) to assess the acute stage of infection and 90, 120 and 180 d. p.i. for chronic stage analysis. ELISA showed values higher than the cut-off of specific IgM and IgG at 7 d. p.i. with significant differences at 0 and 7 d. p.i. for IgM and at 14, 21 and 28 d. p.i. for IgG in the acute stage. Higher and stable levels were detected in the chronic stage. Western Blot showed bands from 102 to 38 kDa detected by specific IgM and IgG. More immunogenic bands were identified by specific IgG. In the chronic stage of infection a band near 31 kDa was the only band detected by IgM until 150 d. p.i. Specific IgG recognized bands between 102 and 31 kDa. This study demonstrates how the humoral immune response evolves in the acute and chronic stages of infection and provides evidence on the role of the pig as a paratenic host of T. cati.


Assuntos
Anticorpos Anti-Helmínticos/biossíntese , Imunidade Humoral , Doenças dos Suínos/imunologia , Toxocara/imunologia , Toxocaríase/imunologia , Análise de Variância , Animais , Anticorpos Anti-Helmínticos/sangue , Área Sob a Curva , Western Blotting , Gatos , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Fezes/parasitologia , Imunoglobulina G/biossíntese , Imunoglobulina G/sangue , Imunoglobulina M/biossíntese , Imunoglobulina M/sangue , Masculino , Curva ROC , Sensibilidade e Especificidade , Suínos , Doenças dos Suínos/parasitologia , Toxocaríase/parasitologia
6.
Korean J Parasitol ; 58(4): 413-419, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32871635

RESUMO

Eosinophilia occurs commonly in many diseases including allergic diseases and helminthic infections. Toxocariasis has been suggested as one cause of eosinophilia. The present study was undertaken to examine the prevalence of toxocariasis in patients with eosinophilia and to identify the risk factors for toxocariasis. This prospective cohort study recruited a total of 81 patients with eosinophilia (34 males and 47 females) who visited the outpatient clinic at Seoul National University Hospital from January 2017 to February 2018 and agreed to participate in this study. The prevalence of toxocariasis was examined by T. canis-specific ELISA, and the various risk factors for toxocariasis were evaluated by a questionnaire survey. Among 81 patients with eosinophilia, 18 were positive for anti-T. canis antibodies (22.2%); 88.9% were male (16/18) and 11.1% were female (2/18). Multivariate statistical analysis revealed that males (OR 21.876, 95% CI: 1.667-287.144) with a history of consuming the raw meat or livers of animals (OR 5.899, 95% CI: 1.004-34.669) and a heavy alcohol-drinking habit (OR 8.767, 95% CI: 1.018-75.497) were at higher risk of toxocariasis in patients with eosinophilia. Toxocariasis should be considered a potential cause of eosinophilia when the patient has a history of eating the raw meat or livers of animals in Korea. A single course of albendazole is recommended to reduce the migration of Toxocara larvae in serologically positive cases with eosinophilia.


Assuntos
Eosinofilia/etiologia , Toxocaríase/complicações , Toxocaríase/epidemiologia , Alcoolismo , Animais , Anticorpos Anti-Helmínticos/sangue , Biomarcadores/sangue , Estudos de Coortes , Ensaio de Imunoadsorção Enzimática , Eosinofilia/epidemiologia , Comportamento Alimentar , Feminino , Humanos , Masculino , Carne/efeitos adversos , Prevalência , Estudos Prospectivos , República da Coreia/epidemiologia , Fatores de Risco , Inquéritos e Questionários , Toxocara canis/imunologia , Toxocaríase/diagnóstico , Toxocaríase/parasitologia
8.
Am J Trop Med Hyg ; 103(2): 723-726, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32431278

RESUMO

Meningoencephalitis is not a rare disease in small children. However, eosinophilic meningitis due to Angiostrongylus cantonensis is unusual in a baby. We describe the case of a 9-month-old baby from North Vietnam with eosinophilic meningoencephalitis. The baby lived in a rural area, where farming is widespread, and presented with fever and seizures. Laboratory results showed peripheral eosinophilia (16.1%), cerebrospinal fluid (CSF) white blood cell count 220/mm3 (26% eosinophils), CSF antibody test positive for Ascaris, CSF ELISA positive for Angiostrongylus cantonensis, and blood ELISA positive for A. cantonensis. A mobile worm was identified in the CSF. The presentation was consistent with a diagnosis of A. cantonensis eosinophilic meningitis. The baby recovered fully after administering albendazole (200 mg/day for 2 weeks), and intravenous dexamethasone (0.6 mg/kg/day every 8 hours) and mannitol (1.5 g/kg/day every 8 hours) for the first 3 days, followed by 5 days of oral prednisolone (2 mg/kg/day).


Assuntos
Angiostrongylus cantonensis/isolamento & purificação , Eosinofilia/sangue , Meningoencefalite/fisiopatologia , Infecções por Strongylida/fisiopatologia , Albendazol/uso terapêutico , Animais , Anti-Helmínticos/uso terapêutico , Anti-Inflamatórios/uso terapêutico , Anticorpos Anti-Helmínticos/sangue , Anticorpos Anti-Helmínticos/líquido cefalorraquidiano , Dexametasona/uso terapêutico , Diuréticos Osmóticos/uso terapêutico , Eosinofilia/etiologia , Humanos , Lactente , Hipertensão Intracraniana/tratamento farmacológico , Hipertensão Intracraniana/etiologia , Imagem por Ressonância Magnética , Masculino , Manitol/uso terapêutico , Meningoencefalite/complicações , Meningoencefalite/tratamento farmacológico , Meningoencefalite/metabolismo , Prednisolona/uso terapêutico , Convulsões/etiologia , Convulsões/fisiopatologia , Infecções por Strongylida/complicações , Infecções por Strongylida/tratamento farmacológico , Infecções por Strongylida/metabolismo , Tomografia Computadorizada por Raios X , Vietnã
9.
Parasite Immunol ; 42(7): e12728, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32394439

RESUMO

Helminth infection represents a major health problem causing approximately 5 million disability-adjusted life years worldwide. Concerns that repeated anti-helminthic treatment may lead to drug resistance render it important that vaccines are developed but will require increased understanding of the immune-mediated cellular and antibody responses to helminth infection. IL-4 or antibody-activated murine macrophages are known to immobilize parasitic nematode larvae, but few studies have addressed whether this is translatable to human macrophages. In the current study, we investigated the capacity of human macrophages to recognize and attack larval stages of Ascaris suum, a natural porcine parasite that is genetically similar to the human helminth Ascaris lumbricoides. Human macrophages were able to adhere to and trap A suum larvae in the presence of either human or pig serum containing Ascaris-specific antibodies and other factors. Gene expression analysis of serum-activated macrophages revealed that CCL24, a potent eosinophil attractant, was the most upregulated gene following culture with A suum larvae in vitro, and human eosinophils displayed even greater ability to adhere to, and trap, A suum larvae. These data suggest that immune serum-activated macrophages can recruit eosinophils to the site of infection, where they act in concert to immobilize tissue-migrating Ascaris larvae.


Assuntos
Ascaríase/imunologia , Ascaris suum/imunologia , Quimiocina CCL24/metabolismo , Eosinófilos/imunologia , Macrófagos/imunologia , Animais , Anticorpos Anti-Helmínticos/sangue , Formação de Anticorpos , Ascaris lumbricoides/imunologia , Humanos , Soros Imunes/farmacologia , Larva/imunologia , Contagem de Leucócitos , Camundongos , Suínos , Doenças dos Suínos/imunologia , Vacinas/imunologia
11.
PLoS Negl Trop Dis ; 14(5): e0008187, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32453734

RESUMO

Loiasis, caused by the filarial nematode Loa loa, is endemic in Central and West Africa where about 10 million people are infected. There is a scarcity of convenient, commercial diagnostics for L. loa. Microscopy requires trained personnel and has low sensitivity, while the serodiagnosis is currently not standardized. Individual case management is also important in non-endemic countries to treat migrants, expatriates and tourists. We retrospectively compared the performance of a Loa Antibody Rapid Test (RDT) and a commercial ELISA pan-filarial test on 170 patients, 65 with loiasis [8 with eyeworm, 29 with positive microfilaremia, 28 with neither microfilaremia nor history of eyeworm but eosinophilia and history of Calabar swelling (probable loiasis)], 95 with other common parasitic infections and no previous exposure to L. loa (37 with M. perstans, 1 with Brugia sp., 18 with strongyloidiasis, 20 with schistosomiasis, 5 with hookworm, 4 with Ascaris lumbricoides infection, 10 with hyper-reactive malarial splenomegaly), and 10 uninfected controls. The sensitivity of the RDT and of the ELISA were 93.8% (61/65) and 90.8% (59/65), respectively. For the RDT, most of the cross-reactions were observed in patients with M. perstans: 7/37 (18.9%), followed by 1/10 (10%) with hyper-reactive malarial splenomegaly and 1/20 (5%) with schistosomiasis. None of the 27 subjects infected with intestinal nematodes was found positive at this test. The ELISA is meant to be a pan-filarial assay, and reacted extensively with cases of M. perstans (95%), as expected, and also in 11/18 (61.1%) patients with strongyloidiasis and in 3/5 (60%) with hookworm infection. The RDT and the ELISA are both highly sensitive for the diagnosis of loiasis. The main difference lies in the extent of cross-reactivity with other parasites. Considering that the RDT is specifically meant for Loa loa infection, and its high sensitivity, this test could be a useful tool for the diagnosis of occult loiasis.


Assuntos
Anticorpos Anti-Helmínticos/sangue , Loíase/sangue , Loíase/diagnóstico , Testes Sorológicos/métodos , Adulto , Feminino , Humanos , Masculino , Sensibilidade e Especificidade , Adulto Jovem
12.
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
13.
PLoS Negl Trop Dis ; 14(4): e0008037, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32282815

RESUMO

BACKGROUND: The scientific community has recently summarized the desired characteristics for diagnostic tools across the different phases of a soil-transmitted helminth (STH) mass drug administration (MDA) program. Although serology meets some of the desired criteria, there is a scarcity of data on baseline serological profiles in human populations, both prior to and during MDA programs. METHODS: In this study, we compared the copromicroscopic and the serological infection profiles in 600 school-aged children (SAC) and 600 adults at the advent of the MDA program in Jimma Town, Ethiopia. The serological profiles were examined by two ELISAs that measure IgG4 responses to the Ascaris suum haemoglobin antigen (AsHb) and a somatic extract of lung stage larvae (AsLungL3). Three years into the MDA program, we sampled another group of 600 SAC from the same schools to assess the reduction in prevalence and intensity of Ascaris infections measured by copromicroscopy and serology. PRINCIPAL FINDINGS: Prior to the start of MDA, copromicroscopy revealed an Ascaris prevalence of 31.0% and a mean fecal egg count of 2,919 eggs per gram (EPG) in SAC. Following three years of biannual treatment, the prevalence reduced to 13.2% (57.8% reduction) and the mean fecal egg count to 1,513 EPG (48.1% reduction). This reduction was also reflected in the serological results. The seroprevalence reduced with 40.9% and 27.4% and the mean optical density ratio reduced with 44.2% and 38.2% as measured by the AsHb or AsLungL3 ELISA respectively. We also showed that, despite a decreasing coproprevalence, seroprevalence to Ascaris increased with age. CONCLUSIONS: This study is the first to provide IgG4 response profiles of an endemic population to two different A. suum antigens. The results suggest that exposure to the infectious stages of Ascaris reaches beyond SAC alone. Furthermore, it highlights the possible use of serological assays to monitor changes in STH exposure during MDA programs.


Assuntos
Ascaríase/diagnóstico , Ascaris suum/imunologia , Ascaris suum/isolamento & purificação , Monitoramento de Medicamentos/métodos , Administração Massiva de Medicamentos/métodos , Microscopia/métodos , Testes Sorológicos/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Anticorpos Anti-Helmínticos/sangue , Antígenos de Helmintos/imunologia , Ascaríase/tratamento farmacológico , Ascaríase/epidemiologia , Ascaríase/prevenção & controle , Criança , Pré-Escolar , Estudos Transversais , Ensaio de Imunoadsorção Enzimática/métodos , Etiópia/epidemiologia , Fezes/parasitologia , Feminino , Humanos , Imunoglobulina G/sangue , Masculino , Pessoa de Meia-Idade , Prevalência , Resultado do Tratamento , Adulto Jovem
14.
Parasit Vectors ; 13(1): 154, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-32228657

RESUMO

BACKGROUND: Methyltransferases (MTFs) are broad range of enzymes, which are ubiquitously expressed in diverse organisms ranging from bacteria to animals. MTFs proteins have been associated with various biological/cellular processes including transcriptional regulation, subcellular protein and RNA localization, signal transduction and DNA-damage repair. However, the role of MTFs in immune mechanism during host-parasite interaction has not been addressed yet. RESULTS: An open reading frame (764 bp) of methyltransferase-type 12 gene of H. contortus denoted as HcMTF-12, was successfully cloned using reverse transcriptase-polymerase chain reaction (RT-PCR) followed by prokaryotic expression in Escherichia coli BL21 (DE3 strain). The recombinant HcMTF-12 protein (rHcMTF-12) was about 47 kDa along with a fusion vector protein of 18 kDa. Immunoblot results identified the native protein MTF-12 with antibodies produced in rats against rHcMT-12, whereas rHcMTF-12 protein was recognized with sera of goat experimentally infected with H. contortus. Immunohistochemical analysis revealed that the native MTF-12 protein was mainly located in the periphery (cuticle) of parasite sections as well as within the pharynx and intestinal region. An immunofluorescence assay validated that rHcMTF-12 attached to the surface of goat PBMCs. Furthermore, the cytokines transcription of IL-2, IFN-γ and IL-4 transcripts of PBMCs incubated with rHcMTF-12 were enhanced in a dose-dependent manner. The secretion of TGF-ß1 and IL-10 was significantly decreased. However, IL-6 production was not significantly different as compared to the control groups. Moreover, the migration activity and nitric oxide (NO) production by PBMCs were induced considerably, whereas the proliferation of PBMCs cells was negatively affected when incubated with the rHcMTF-12 protein. CONCLUSIONS: Our findings suggest that HcMTF-12 significantly mediated the functions of PBMCs, and it might be a potential candidate for therapeutic interventions against haemonchosis.


Assuntos
Cabras/parasitologia , Haemonchus/enzimologia , Haemonchus/genética , Leucócitos Mononucleares/imunologia , Metiltransferases/genética , Metiltransferases/imunologia , Metiltransferases/isolamento & purificação , Animais , Anticorpos Anti-Helmínticos/sangue , Proliferação de Células , Clonagem Molecular , Citocinas/metabolismo , Modelos Animais de Doenças , Escherichia coli/genética , Feminino , Regulação da Expressão Gênica , Hemoncose/parasitologia , Hemoncose/veterinária , Proteínas de Helminto/genética , Interações Hospedeiro-Parasita/imunologia , Masculino , Metiltransferases/metabolismo , Óxido Nítrico/metabolismo , Ratos Sprague-Dawley , Proteínas Recombinantes/genética , Alinhamento de Sequência , Análise de Sequência de Proteína
15.
J Helminthol ; 94: e134, 2020 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-32127056

RESUMO

The enzyme-linked immunosorbent assay (ELISA) technique can play an important role in the early detection of fascioliasis. However, they have some diagnostic limitations, including cross-reaction with other helminths. It seems that the combination of recombinant parasite proteins as antigen can reduce these problems. Hence, the present study was aimed to design and confirm the antigenic recombinant multi-epitope (rMEP) construct of three protein epitopes (linear and conformational B-cell epitopes) of the parasite using immunoinformatic tools. For this purpose, the tertiary structures of Fasciola hepatica cathepsin-L1, saposin-like protein 2 and 16.5-kDa tegument-associated protein were predicted using the I-TASSER server. Validation of the modelled structures was performed by Ramachandran plots. The antigenic epitopes of the proteins were achieved by analysing the features of the IEDB server. The synthesized gene was cloned into the pET-22b (+) expression vector and transformed into the Escherichia coli BL21. Sodium dodecyl sulfate polyacrylamide gel electrophoresis was used to verify and analyse the expression of the rMEP protein. Western blotting was utilized to confirm rMEP protein immunogenicity in two forms, one using an anti-His tag antibody and the other with human pooled sera samples (fascioliasis, non-fascioliasis and negative control sera). Our results demonstrated that the rMEP designed for the three proteins of F. hepatica was highly antigenic, and immune-detection techniques confirmed the antigen specificity. In conclusion, the presented antigenic multi-epitope may be very helpful to develop serodiagnostic kits such as indirect ELISA to evaluate the proper diagnosis of fascioliasis in humans and ruminants.


Assuntos
Antígenos de Helmintos/genética , Catepsinas/química , Fasciola hepatica/genética , Proteínas de Helminto/química , Animais , Anticorpos Anti-Helmínticos/sangue , Antígenos de Helmintos/química , Western Blotting , Catepsinas/genética , Epitopos/imunologia , Escherichia coli/genética , Fasciola hepatica/química , Fasciolíase/diagnóstico , Proteínas de Helminto/genética , Humanos , Proteínas Recombinantes/química
16.
Parasit Vectors ; 13(1): 125, 2020 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-32164780

RESUMO

BACKGROUND: Prevalence of lymphatic filariasis (LF) antigen in American Samoa was 16.5% in 1999. Seven rounds of mass drug administration (MDA) programmes between 2000 and 2006 reduced antigen prevalence to 2.3%. The most efficient methods of surveillance after MDA are not clear, but testing specific at-risk groups such as adults may provide earlier warning of resurgence. The role of migration from LF endemic countries in maintaining transmission also needs investigation. Few studies have investigated knowledge about LF and how that relates to infection risk. This study aims to investigate associations between socio-demographics, population mobility, disease knowledge and LF infection risk. METHODS: In 2014, we surveyed 670 adults aged 16-68 years (62% female) at two worksites in American Samoa. Sera were tested for LF antigen and antibodies (Bm14 and Wb123) by rapid test and/or ELISA. Multivariate logistic regression was used to assess association between seromarkers and demographic factors, household socioeconomic status (SES), residence, travel history, and knowledge of LF. RESULTS: Overall, 1.8% of participants were positive for antigen, 11.8% for Bm14, 11.3% for Wb123 and 17.3% for at least one antibody. Recent travel outside American Samoa was not associated with positivity for any seromarker. Men had higher seroprevalence than women for all outcomes (any antibody: adjusted odds ratio (aOR) = 3.49 (95% CI: 2.21-5.49). Those aged over 35 years (compared to 15-24 years) had higher prevalence of Bm14 antibody (aOR = 3.75, 3.76 and 4.17 for ages 35-44, 45-54 and ≥ 55 years, respectively, P < 0.05). Lower SES was associated with seropositivity (antigen: aOR = 2.89, 95% CI: 1.09-7.69; either antibody: aOR = 1.51, 95% CI: 1.12-2.05). Those who knew that mosquitoes transmitted LF had lower Wb123 antibody prevalence (aOR = 0.55, 95% CI: 0.32-0.95). CONCLUSIONS: Opportunistic sampling of adults at worksites provided an efficient and representative way to assess prevalence and risk factors for LF in American Samoa and in hindsight, foreshadowed the resurgence of transmission. Risk of LF infection, detected by one or more serological markers, was not related to recent travel history, but was strongly associated with male gender, older age, lower SES, and lack of knowledge about mosquito transmission. These results could guide future efforts to increase MDA participation.


Assuntos
Demografia , Filariose Linfática/epidemiologia , Conhecimentos, Atitudes e Prática em Saúde , Mobilidade Social , Fatores Socioeconômicos , Adolescente , Adulto , Idoso , Samoa Americana/epidemiologia , Animais , Anticorpos Anti-Helmínticos/sangue , Antígenos de Helmintos/sangue , Culicidae , Filariose Linfática/transmissão , Doenças Endêmicas , Monitoramento Epidemiológico , Características da Família , Feminino , Humanos , Modelos Logísticos , Masculino , Administração Massiva de Medicamentos , Pessoa de Meia-Idade , Análise Multivariada , Prevalência , Medição de Risco , Fatores de Risco , Estudos Soroepidemiológicos , Inquéritos e Questionários , Viagem , Adulto Jovem
17.
Exp Parasitol ; 212: 107867, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32199081

RESUMO

Trichinellosis is a serious foodborne zoonotic disease. It is an important threat to public health all over the world. Although anti-Trichinella IgG detection is the most widely used method for diagnosis of trichinellosis, but there is an obvious window between clinical symptoms and positive serology. Gold nanoparticles (AuNPs) can be conjugated with antibodies affording them promising applications for bio-chemical detection. Herein, AuNPs-based ELISA was evaluated for the first time in the detection of Trichinella spiralis circulating antigen (CAg) for its potential as a diagnostic tool of experimental infection. Swiss Albino mice were orally inoculated with 100 muscle larvae/mouse. Animals were sacrificed 6, 8, 10, 12, 14, 16, 22 and 28 day-post infection (dpi). Blood samples were tested for CAg by both standard ELISA and nano-based ELISA using anti-rabbit polyclonal IgG conjugated with AuNPs. CAg was only detected by nano-based ELISA 6, 8, 10 dpi and by both formats 12-28 dpi. Nano-based assay recorded a statistically significant high sensitivity (58.33%, 91.67%) and accuracy (72.22%, 94.44%) 8 and 10 dpi, respectively in comparison to standard ELISA. Both assays showed high sensitivity and accuracy 12-28 dpi. Thus, nano-based ELISA could be considered as an early sensitive diagnostic method for experimental trichinellosis.


Assuntos
Antígenos de Helmintos/sangue , Ensaio de Imunoadsorção Enzimática/métodos , Doenças Transmitidas por Alimentos/diagnóstico , Nanopartículas Metálicas/química , Trichinella spiralis/imunologia , Triquinelose/diagnóstico , Animais , Anticorpos Anti-Helmínticos/sangue , Modelos Animais de Doenças , Doenças Transmitidas por Alimentos/parasitologia , Ouro/química , Imunoglobulina G/sangue , Masculino , Camundongos , Músculo Esquelético/parasitologia , Coelhos , Sensibilidade e Especificidade , Suínos , Fatores de Tempo , Trichinella spiralis/isolamento & purificação , Triquinelose/transmissão , Zoonoses/parasitologia
18.
Parasit Vectors ; 13(1): 97, 2020 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-32093735

RESUMO

BACKGROUND: Trichinella spiralis muscle larval (ML) excretion/secretion (ES) antigen is the most widely used diagnostic antigen of trichinellosis, but preparation of ES antigen requires collecting worms from infected animals, and detection of specific IgG against ML ES antigen may result in a false negative at the early stage of infection. The aim of the study was to characterize T. spiralis elastase-1 (TsEla) and to evaluate its potential as diagnostic antigen for trichinellosis. METHODS: The complete cDNA sequences of the TsEla gene were cloned and expressed, and recombinant (rTsEla) was purified. TsEla transcription and expression in different T. spiralis life-cycle stages was investigated by qPCR and western blotting, and its location in the nematodes was evaluated using an immunofluorescence assay (IFA). The antigenicity of rTsEla was investigated by western blotting analysis and ELISA. Anti-Trichinella IgG, IgM and IgE of experimentally infected mice and specific IgG antibodies of trichinellosis patients were assayed by rTsEla-ELISA and ES-ELISA. RESULTS: The results of the qPCR and western blotting showed that TsEla was expressed in various T. spiralis life stages. Natural TsEla was detected in the soluble proteins and ES proteins of different life stages. IFA revealed that TsEla was identified in the whole nematodes of various stages, especially in the cuticle, stichosome and genital primordium of the parasite. Serum anti-Trichinella IgM, IgG and IgE in infected mice was first detected by rTsEla-ELISA at 6, 10 and 12 days post-infection (dpi), and reached 100% at 8, 14 and 14 dpi, respectively. When rTsEla-ELISA and ES-ELISA were used to detect anti-Trichinella IgG in sera of trichinellosis patients, the sensitivity was 97.37% (37/38) and 89.74% (34/38) (P > 0.05), and the specificity was 99.10% (220/222) and 98.20% (218/222), respectively (P > 0.05). The rTsEla cross-reacted with only one serum sample out of 20 samples from paragonimiasis patients and 7 samples from clonorchiasis patients. CONCLUSIONS: rTsEla is valuable to early diagnosis of trichinellosis and could be an alternative diagnostic antigen to the ML ES antigens.


Assuntos
Antígenos de Helmintos/genética , Antígenos de Helmintos/imunologia , Elastase Pancreática/química , Elastase Pancreática/imunologia , Trichinella spiralis/enzimologia , Triquinelose/diagnóstico , Sequência de Aminoácidos , Animais , Anticorpos Anti-Helmínticos/sangue , Antígenos de Helmintos/química , Western Blotting , Ensaio de Imunoadsorção Enzimática , Feminino , Proteínas de Helminto/genética , Proteínas de Helminto/imunologia , Humanos , Estágios do Ciclo de Vida , Camundongos Endogâmicos BALB C , Elastase Pancreática/genética , Alinhamento de Sequência , Trichinella spiralis/genética , Trichinella spiralis/crescimento & desenvolvimento , Trichinella spiralis/imunologia , Triquinelose/sangue , Triquinelose/imunologia , Triquinelose/parasitologia
19.
Parasit Vectors ; 13(1): 60, 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-32051006

RESUMO

BACKGROUND: Ascariasis, caused by Ascaris suum, is an important soil-transmitted parasitic disease of pigs worldwide. It leads to significant economic losses in the pork industry, as a consequence of low feed conversion efficiency in pigs and liver condemnation at slaughter. Despite ascariasis still being widespread on pig farms in many developing and the industrialised countries, there are surprisingly limited data on porcine ascariasis in China, where nearly half of the world's total pork is produced. METHODS: In the present study, using the recently developed A. suum-haemoglobin (As-Hb) antigen-based serological test, we screened 512 individual serum samples from fattening pigs from 13 farms across seven distinct locations of Sichuan Province in China for anti-Ascaris antibody. RESULTS: The prevalence of anti-Ascaris antibody ranged from 0% to 100% on the distinct farms, with the mean (overall) seroprevalence being > 60%. There was no significant difference in seroprevalence between the intensive and extensive farms. CONCLUSIONS: To our knowledge, this is the first study to measure anti-Ascaris seroprevalence in China. The results of this 'snapshot' investigation indicate that Ascaris infection in commercial pig farms in Sichuan Province is seriously underestimated, encouraging future, large-scale serological studies to assess the distribution and extent of Ascaris exposure and infection in various regions of China and the world.


Assuntos
Anticorpos Anti-Helmínticos/sangue , Ascaríase/veterinária , Ascaris suum/isolamento & purificação , Doenças dos Suínos/epidemiologia , Animais , Ascaríase/epidemiologia , China/epidemiologia , Gerenciamento Clínico , Fazendas , Indústria Alimentícia , Fígado/parasitologia , Carne de Porco/parasitologia , Estudos Soroepidemiológicos , Testes Sorológicos , Suínos/parasitologia , Doenças dos Suínos/parasitologia
20.
PLoS Negl Trop Dis ; 14(2): e0008057, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32053593

RESUMO

BACKGROUND: Ascaris lumbricoides is one of the three major soil-transmitted gastrointestinal helminths (STHs) that infect more than 440 million people in the world, ranking this neglected tropical disease among the most common afflictions of people living in poverty. Children infected with this roundworm suffer from malnutrition, growth stunting as well as cognitive and intellectual deficits. An effective vaccine is urgently needed to complement anthelmintic deworming as a better approach to control helminth infections. As37 is an immunodominant antigen of Ascaris suum, a pig roundworm closely related to the human A. lumbricoides parasite, recognized by protective immune sera from A. suum infected mice. In this study, the immunogenicity and vaccine efficacy of recombinant As37 were evaluated in a mouse model. METHODOLOGY/PRINCIPAL FINDINGS: As37 was cloned and expressed as a soluble recombinant protein (rAs37) in Escherichia coli. The expressed rAs37 was highly recognized by protective immune sera from A. suum egg-infected mice. Balb/c mice immunized with 25 µg rAs37 formulated with AddaVax™ adjuvant showed significant larval worm reduction after challenge with A. suum infective eggs when compared with a PBS (49.7%) or adjuvant control (48.7%). Protection was associated with mixed Th1/2-type immune responses characterized by high titers of serological IgG1 and IgG2a and stimulation of the production of cytokines IL-4, IL-5, IL-10 and IL-13. In this experiment, the AddaVax™ adjuvant induced better protection than the Th1-type adjuvant MPLA (38.9%) and the Th2-type adjuvant Alhydrogel (40.7%). Sequence analysis revealed that As37 is a member of the immunoglobulin superfamily (IgSF) and highly conserved in other human STHs. Anti-As37 antibodies strongly recognized homologs in hookworms (Necator americanus, Ancylostoma ceylanicum, A. caninum) and in the whipworm Trichuris muris, but there was no cross-reaction with human spleen tissue extracts. These results suggest that the nematode-conserved As37 could serve as a pan-helminth vaccine antigen to prevent all STH infections without cross-reaction with human IgSF molecules. CONCLUSIONS/SIGNIFICANCE: As37 is an A. suum expressed immunodominant antigen that elicited significant protective immunity in mice when formulated with AddaVax™. As37 is highly conserved in other STHs, but not in humans, suggesting it could be further developed as a pan-helminth vaccine against STH co-infections.


Assuntos
Ascaríase/imunologia , Ascaris suum/metabolismo , Proteínas de Helminto/imunologia , Sequência de Aminoácidos , Animais , Anticorpos Anti-Helmínticos/sangue , Antígenos de Helmintos/imunologia , Ascaris suum/genética , Ascaris suum/imunologia , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Filogenia , Solo/parasitologia
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