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1.
J Clin Microbiol ; 59(11): e0045821, 2021 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-34432487

RESUMO

Babesia duncani is the causative agent of babesiosis in the western United States. The indirect fluorescent antibody (IFA) assay is the diagnostic test of choice for detection of B. duncani-specific antibodies. However, this test requires parasitized red blood cells harvested from infected hamsters, and test results are often difficult to interpret. To simplify serological testing for B. duncani, a proteomics approach was employed to identify candidate immunodiagnostic antigens. Several proteins were identified by electrospray ionization mass spectrometric analysis, and four recombinant protein constructs were expressed and used in a multiplex bead assay (MBA) to detect B. duncani-specific antibodies. Two antigens, AAY83295.1 and AAY83296.1, performed well with high sensitivities and specificities. AAY83295.1 had a higher sensitivity (100%) but lower specificity (89%) than AAY83296.1, which had a sensitivity of 90% and a specificity of 96%. Combining these two antigens did not improve the performance of the assay. This MBA could be useful for diagnosis, serosurveillance, and blood donor screening for B. duncani infection.


Assuntos
Babesia , Babesiose , Animais , Anticorpos Antiprotozoários , Babesia/genética , Babesiose/diagnóstico , Cricetinae , Eritrócitos , Técnica Indireta de Fluorescência para Anticorpo , Humanos , Imunoglobulina G , Estados Unidos
2.
Rev Peru Med Exp Salud Publica ; 37(1): 104-109, 2020.
Artigo em Espanhol, Inglês | MEDLINE | ID: mdl-32520171

RESUMO

The use of L protein coupled magnetic particles for the concentration and purification of immunoglobulin M (mIgM) monoclonal antibodies against Taenia solium was evaluated. Three concentration methods and different elution times were evaluated and the ratio of particles to the ratio of mIgM was optimized. It is demonstrated that: 1) with the use of magnetic particles, a previous concentration of mIgM is not required, which reduces the manipulation of the antibodies and improves the recovery, 2) the use of a binding buffer can be omitted, since the pH of most cell culture supernatants are neutral, and 3) longer elution times (~ 45 minutes) are needed to increase recovery to a level greater than 80%. The study demonstrates that the use of L protein-coupled magnetic particles is a simple and efficient tool for mIgM concentration and purification.


Se evaluó el uso de partículas magnéticas acopladas a proteína L para la concentración y purificación de anticuerpos monoclonales inmunoglobulina M (mIgM) contra Taenia solium. Se evaluaron tres métodos de concentración y diferentes tiempos de elución y se optimizó la proporción de partículas a la proporción de mIgM. Demostramos que: 1) con el uso partículas magnéticas no se requiere de una concentración previa de mIgM, lo que disminuye la manipulación de los anticuerpos y mejora la recuperación, 2) se puede omitir el uso de un tampón de unión, ya que el pH de la mayoría de los sobrenadantes de cultivo celular son neutros, y 3) se necesitan tiempos de elución más largos (~45 minutos) para aumentar la recuperación a un nivel mayor a 80%. El estudio demuestra que el uso de partículas magnéticas acopladas a proteína L es una herramienta simple y eficiente para la concentración y purificación de mIgM.


Assuntos
Anticorpos Monoclonais , Imunoglobulina M , Fenômenos Magnéticos , Taenia solium , Animais , Anticorpos Monoclonais/isolamento & purificação , Imunoglobulina M/imunologia , Taenia solium/imunologia
3.
Rev. peru. med. exp. salud publica ; 37(1): 104-109, ene.-mar. 2020. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-1101816

RESUMO

RESUMEN Se evaluó el uso de partículas magnéticas acopladas a proteína L para la concentración y purificación de anticuerpos monoclonales inmunoglobulina M (mIgM) contra Taenia solium. Se evaluaron tres métodos de concentración y diferentes tiempos de elución y se optimizó la proporción de partículas a la proporción de mIgM. Demostramos que: 1) con el uso partículas magnéticas no se requiere de una concentración previa de mIgM, lo que disminuye la manipulación de los anticuerpos y mejora la recuperación, 2) se puede omitir el uso de un tampón de unión, ya que el pH de la mayoría de los sobrenadantes de cultivo celular son neutros, y 3) se necesitan tiempos de elución más largos (~45 minutos) para aumentar la recuperación a un nivel mayor a 80%. El estudio demuestra que el uso de partículas magnéticas acopladas a proteína L es una herramienta simple y eficiente para la concentración y purificación de mIgM.


ABSTRACT The use of L protein coupled magnetic particles for the concentration and purification of immunoglobulin M (mIgM) monoclonal antibodies against Taenia solium was evaluated. Three concentration methods and different elution times were evaluated and the ratio of particles to the ratio of mIgM was optimized. It is demonstrated that: 1) with the use of magnetic particles, a previous concentration of mIgM is not required, which reduces the manipulation of the antibodies and improves the recovery, 2) the use of a binding buffer can be omitted, since the pH of most cell culture supernatants are neutral, and 3) longer elution times (~ 45 minutes) are needed to increase recovery to a level greater than 80%. The study demonstrates that the use of L protein-coupled magnetic particles is a simple and efficient tool for mIgM concentration and purification.


Assuntos
Animais , Imunoglobulina M , Taenia solium , Fenômenos Magnéticos , Anticorpos Monoclonais , Imunoglobulina M/imunologia , Taenia solium/imunologia , Anticorpos Monoclonais/isolamento & purificação
4.
PLoS Negl Trop Dis ; 13(12): e0007751, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31809501

RESUMO

In Africa, urbanization is happening faster than ever before which results in new implications for transmission of infectious diseases. For the zoonotic parasite Taenia solium, a major cause of acquired epilepsy in endemic countries, the prevalence in urban settings is unknown. The present study investigated epidemiological, neurological, and radiological characteristics of T. solium cysticercosis and taeniasis (TSCT) in people with epilepsy (PWE) living in Dar es Salaam, Tanzania, one of the fastest growing cities worldwide. A total of 302 PWE were recruited from six health centers in the Kinondoni district of Dar es Salaam. Serological testing for T. solium cysticercosis-antigen (Ag) and -antibodies (Abs) and for T. solium taeniasis-Abs was performed in all PWE. In addition, clinical and radiological examinations that included cranial computed tomography (CT) were performed. With questionnaires, demographic data from study populations were collected, and factors associated with TSCT were assessed. Follow-up examinations were conducted in PWE with TSCT. T. solium cysticercosis-Ag was detected in three (0.99%; 95% CI: 0-2.11%), -Abs in eight (2.65%; 95% CI: 0.84-4.46%), and taeniasis-Abs in five (1.66%; 95% CI: 0.22-3.09%) of 302 PWE. Six PWE (1.99%; 95% CI: 0.41-3.56%) were diagnosed with neurocysticercosis (NCC). This study demonstrates the presence of TSCT in Dar es Salaam, however, NCC was only associated with a few cases of epilepsy. The small fraction of PWE with cysticercosis- and taeniasis-Abs may suggest that active transmission of T. solium plays only a minor role in Dar es Salaam. A sufficiently powered risk analysis was hampered by the small number of PWE with TSCT; therefore, further studies are required to determine the exact routes of infection and risk behavior of affected individuals.


Assuntos
Cisticercose/complicações , Cisticercose/epidemiologia , Epilepsia/epidemiologia , Epilepsia/etiologia , Taenia solium/isolamento & purificação , População Urbana , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Criança , Cidades/epidemiologia , Cisticercose/diagnóstico por imagem , Cisticercose/patologia , Epilepsia/diagnóstico por imagem , Epilepsia/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Medição de Risco , Inquéritos e Questionários , Tanzânia/epidemiologia , Tomografia Computadorizada por Raios X , Adulto Jovem
5.
Vector Borne Zoonotic Dis ; 19(8): 563-575, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30789314

RESUMO

Background: Due to their close relationship with the environment, Alaskans are at risk for zoonotic pathogen infection. One way to assess a population's disease burden is to determine the seroprevalence of pathogens of interest. The objective of this study was to determine the seroprevalence of 11 zoonotic pathogens in people living in Alaska. Methods: In a 2007 avian influenza exposure study, we recruited persons with varying wild bird exposures. Using sera from this study, we tested for antibodies to Cryptosporidium spp., Echinococcus spp., Giardia intestinalis, Toxoplasma gondii, Trichinella spp., Brucella spp., Coxiella burnetii, Francisella tularensis, California serogroup bunyaviruses, and hepatitis E virus (HEV). Results: Eight hundred eighty-seven persons had sera tested, including 454 subsistence bird hunters and family members, 160 sport bird hunters, 77 avian wildlife biologists, and 196 persons with no wild bird exposure. A subset (n = 481) of sera was tested for California serogroup bunyaviruses. We detected antibodies to 10/11 pathogens. Seropositivity to Cryptosporidium spp. (29%), California serotype bunyaviruses (27%), and G. intestinalis (19%) was the most common; 63% (301/481) of sera had antibodies to at least one pathogen. Using a multivariable logistic regression model, Cryptosporidium spp. seropositivity was higher in females (35.7% vs. 25.0%; p = 0.01) and G. intestinalis seropositivity was higher in males (21.8% vs. 15.5%; p = 0.02). Alaska Native persons were more likely than non-Native persons to be seropositive to C. burnetii (11.7% vs. 3.8%; p = 0.005) and less likely to be seropositive to HEV (0.4% vs. 4.1%; p = 0.01). Seropositivity to Cryptosporidium spp., C. burnetii, HEV, and Echinococcus granulosus was associated with increasing age (p ≤ 0.01 for all) as was seropositivity to ≥1 pathogen (p < 0.0001). Conclusion: Seropositivity to zoonotic pathogens is common among Alaskans with the highest to Cryptosporidium spp., California serogroup bunyaviruses, and G. intestinalis. This study provides a baseline for use in assessing seroprevalence changes over time.


Assuntos
Infecções Bacterianas/epidemiologia , Doenças Parasitárias/epidemiologia , Viroses/epidemiologia , Zoonoses/epidemiologia , Alaska/epidemiologia , Animais , Animais Selvagens , Regiões Árticas/epidemiologia , Infecções Bacterianas/sangue , Aves , Feminino , Humanos , Masculino , Doenças Parasitárias/sangue , Estudos Soroepidemiológicos , Viroses/sangue , Zoonoses/sangue
6.
Trop Med Int Health ; 23(1): 101-105, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29160912

RESUMO

OBJECTIVE: To evaluate the diagnostic performance of two commercially available ELISA kits, Novalisa® and Ridascreen® , for the detection of antibodies to Taenia solium, compared to serological diagnosis of neurocysticercosis (NCC) by LLGP-EITB (electro-immunotransfer blot assay using lentil-lectin purified glycoprotein antigens). METHODS: Archive serum samples from patients with viable NCC (n = 45) or resolved, calcified NCC (n = 45), as well as sera from patients with other cestode parasites (hymenolepiasis, n = 45 and cystic hydatid disease, n = 45), were evaluated for cysticercosis antibody detection using two ELISA kits, Novalisa® and Ridascreen® . All NCC samples had previously tested positive, and all samples from heterologous infections were negative on LLGP-EITB for cysticercosis. Positive rates were calculated by kit and sample group and compared between the two kits. RESULTS: Compared to LLGP-EITB, the sensitivity of both ELISA assays to detect specific antibodies in patients with viable NCC was low (44.4% and 22.2%), and for calcified NCC, it was only 6.7% and 4.5%. Sera from patients with cystic hydatid disease were highly cross-reactive in both ELISA assays (38/45, 84.4%; and 25/45, 55.6%). Sera from patients with hymenolepiasis cross-reacted in five cases in one of the assays (11.1%) and in only one sample with the second assay (2.2%). CONCLUSIONS: The performance of Novalisa® and Ridascreen® was poor. Antibody ELISA detection cannot be recommended for the diagnosis of neurocysticercosis.


Assuntos
Antígenos de Helmintos/imunologia , Ensaio de Imunoadsorção Enzimática/métodos , Separação Imunomagnética/métodos , Neurocisticercose/diagnóstico , Taenia solium/isolamento & purificação , Animais , Antígenos de Helmintos/sangue , Testes Imunológicos , Neurocisticercose/sangue , Neurocisticercose/parasitologia , Sensibilidade e Especificidade , Taenia solium/imunologia
7.
PLoS Negl Trop Dis ; 11(7): e0005709, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28704366

RESUMO

Despite the global distribution and public health consequences of Taenia tapeworms, the life cycles of taeniids infecting wildlife hosts remain largely undescribed. The larval stage of Taenia serialis commonly parasitizes rodents and lagomorphs, but has been reported in a wide range of hosts that includes geladas (Theropithecus gelada), primates endemic to Ethiopia. Geladas exhibit protuberant larval cysts indicative of advanced T. serialis infection that are associated with high mortality. However, non-protuberant larvae can develop in deep tissue or the abdominal cavity, leading to underestimates of prevalence based solely on observable cysts. We adapted a non-invasive monoclonal antibody-based enzyme-linked immunosorbent assay (ELISA) to detect circulating Taenia spp. antigen in dried gelada urine. Analysis revealed that this assay was highly accurate in detecting Taenia antigen, with 98.4% specificity, 98.5% sensitivity, and an area under the curve of 0.99. We used this assay to investigate the prevalence of T. serialis infection in a wild gelada population, finding that infection is substantially more widespread than the occurrence of visible T. serialis cysts (16.4% tested positive at least once, while only 6% of the same population exhibited cysts). We examined whether age or sex predicted T. serialis infection as indicated by external cysts and antigen presence. Contrary to the female-bias observed in many Taenia-host systems, we found no significant sex bias in either cyst presence or antigen presence. Age, on the other hand, predicted cyst presence (older individuals were more likely to show cysts) but not antigen presence. We interpret this finding to indicate that T. serialis may infect individuals early in life but only result in visible disease later in life. This is the first application of an antigen ELISA to the study of larval Taenia infection in wildlife, opening the doors to the identification and description of infection dynamics in reservoir populations.


Assuntos
Doenças Endêmicas , Ensaio de Imunoadsorção Enzimática/métodos , Doenças dos Primatas/diagnóstico , Doenças dos Primatas/epidemiologia , Taenia/isolamento & purificação , Teníase/veterinária , Urina/parasitologia , Animais , Antígenos de Helmintos/urina , Etiópia/epidemiologia , Feminino , Masculino , Prevalência , Curva ROC , Sensibilidade e Especificidade , Teníase/diagnóstico , Teníase/epidemiologia , Theropithecus/parasitologia
8.
Emerg Infect Dis ; 23(8): 1397-1399, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28726612

RESUMO

Baylisascaris procyonis (raccoon roundworm) infection is common in raccoons and can cause devastating pathology in other animals, including humans. Limited information is available on the frequency of asymptomatic human infection. We tested 150 adults from California, USA, for B. procyonis antibodies; 11 were seropositive, suggesting that subclinical infection does occur.


Assuntos
Infecções por Ascaridida/epidemiologia , Ascaridídios/imunologia , Animais , Infecções por Ascaridida/história , Infecções por Ascaridida/imunologia , California/epidemiologia , Fezes/parasitologia , Feminino , História do Século XXI , Humanos , Masculino , Prevalência , Guaxinins , Estudos Soroepidemiológicos , Zoonoses
9.
Parasitology ; 144(4): 459-463, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27866477

RESUMO

The primary causative agent of eosinophilic meningoencephalitis (EoM) in endemic regions is the nematode Angiostrongylus cantonensis. The occurrence of EoM was previously restricted to countries in Southeast Asia and the Pacific Islands; however, more recently, it has been reported from other regions, including Brazil. The commonly used diagnosis is detection of specific antibody reactivity to the 31 kDa antigen, which is derived from female worm somatic extracts. Here we report the occurrence of cross-reactivity to this antigen in sera from other parasitic infections, especially those that may cause EoM, such as gnathostomiasis, toxocariasis, hydatidosis and strongyloidiasis. We also demonstrated that the cross-reactivity, in part, is dependent of the concentration of antigen used in Western blot assays. We discuss the importance of these findings on the interpretation of this test.


Assuntos
Angiostrongylus cantonensis/imunologia , Antígenos de Helmintos/imunologia , Meningoencefalite/diagnóstico , Meningoencefalite/parasitologia , Infecções por Strongylida/diagnóstico , Angiostrongylus cantonensis/metabolismo , Animais , Reações Cruzadas , Humanos , Meningoencefalite/sangue , Infecções por Strongylida/imunologia , Infecções por Strongylida/parasitologia
10.
Infect Dis Poverty ; 5(1): 111, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-27903304

RESUMO

BACKGROUND: The frequency of Taenia solium, a zoonotic helminth, is increasing in many countries of sub-Saharan Africa, where the prevalence of the human immunodeficiency virus (HIV) is also high. However, little is known about how these two infections interact. The aim of this study was to compare the proportion of HIV positive (+) and negative (-) individuals who are infected with Taenia solium (TSOL) and who present with clinical and neurological manifestations of cysticercosis (CC). METHODS: In northern Tanzania, 170 HIV+ individuals and 170 HIV- controls matched for gender, age and village of origin were recruited. HIV staging and serological tests for TSOL antibodies (Ab) and antigen (Ag) were performed. Neurocysticercosis (NCC) was determined by computed tomography (CT) using standard diagnostic criteria. Neurological manifestations were confirmed by a standard neurological examination. In addition, demographic, clinical and neuroimaging data were collected. Further, CD4+ cell counts as well as information on highly active antiretroviral treatment (HAART) were noted. RESULTS: No significant differences between HIV+ and HIV- individuals regarding the sero-prevalence of taeniosis-Ab (0.6% vs 1.2%), CC-Ab (2.4% vs 2.4%) and CC-Ag (0.6% vs 0.0%) were detected. A total of six NCC cases (3 HIV+ and 3 HIV-) were detected in the group of matched participants. Two individuals (1 HIV+ and 1 HIV-) presented with headaches as the main symptom for NCC, and four with asymptomatic NCC. Among the HIV+ group, TSOL was not associated with CD4+ cell counts, HAART duration or HIV stage. CONCLUSIONS: This study found lower prevalence of taeniosis, CC and NCC than had been reported in the region to date. This low level of infection may have resulted in an inability to find cross-sectional associations between HIV status and TSOL infection or NCC. Larger sample sizes will be required in future studies conducted in that area to conclude if HIV influences the way NCC manifests itself.


Assuntos
Cisticercose/epidemiologia , Infecções por HIV/epidemiologia , Taenia solium/isolamento & purificação , Síndrome da Imunodeficiência Adquirida/epidemiologia , Síndrome da Imunodeficiência Adquirida/virologia , Adolescente , Adulto , Idoso , Animais , Criança , Estudos Transversais , Cisticercose/parasitologia , Feminino , Infecções por HIV/virologia , Soropositividade para HIV/epidemiologia , Soropositividade para HIV/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Neurocisticercose/epidemiologia , Neurocisticercose/parasitologia , Prevalência , Tanzânia/epidemiologia , Adulto Jovem
11.
Emerg Infect Dis ; 22(12): 2128-2131, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27869612

RESUMO

Baylisascaris procyonis roundworms can cause potentially fatal neural larva migrans in many species, including humans. However, the clinical spectrum of baylisascariasis is not completely understood. We tested 347 asymptomatic adult wildlife rehabilitators for B. procyonis antibodies; 24 were positive, suggesting that subclinical baylisascariasis is occurring among this population.


Assuntos
Animais Selvagens , Infecções por Ascaridida/epidemiologia , Infecções por Ascaridida/transmissão , Ascaridoidea , Zoonoses , Animais , Anticorpos Antiprotozoários/sangue , Anticorpos Antiprotozoários/imunologia , Infecções por Ascaridida/história , Infecções por Ascaridida/parasitologia , Ascaridoidea/imunologia , Canadá/epidemiologia , Feminino , Geografia Médica , História do Século XXI , Humanos , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Masculino , Estudos Soroepidemiológicos , Estados Unidos/epidemiologia
12.
Emerg Infect Dis ; 22(11)2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27767010

RESUMO

Babesia microti, an intraerythrocytic parasite, is tickborne in nature. In contrast to transmission by blood transfusion, which has been well documented, transmission associated with solid organ transplantation has not been reported. We describe parasitologically confirmed cases of babesiosis diagnosed ≈8 weeks posttransplantation in 2 recipients of renal allografts from an organ donor who was multiply transfused on the day he died from traumatic injuries. The organ donor and recipients had no identified risk factors for tickborne infection. Antibodies against B. microti parasites were not detected by serologic testing of archived pretransplant specimens. However, 1 of the organ donor's blood donors was seropositive when tested postdonation and had risk factors for tick exposure. The organ donor probably served as a conduit of Babesia parasites from the seropositive blood donor to both kidney recipients. Babesiosis should be included in the differential diagnosis of unexplained fever and hemolytic anemia after blood transfusion or organ transplantation.


Assuntos
Babesia microti , Babesiose/parasitologia , Babesiose/transmissão , Transplante de Órgãos/efeitos adversos , Adulto , Idoso , Babesia microti/genética , Babesia microti/imunologia , Babesiose/diagnóstico , Babesiose/tratamento farmacológico , Biomarcadores , Transfusão de Sangue , Eritrócitos/parasitologia , Eritrócitos/patologia , Humanos , Transplante de Rim/efeitos adversos , Masculino , Fatores de Tempo , Doadores de Tecidos , Tomografia Computadorizada por Raios X , Transplante Homólogo
13.
Transfusion ; 56(6 Pt 2): 1508-19, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26892459

RESUMO

BACKGROUND: Babesiosis is an emerging tick-borne infection in humans. The increasing numbers of reported cases of transfusion-associated babesiosis (TAB), primarily caused by Babesia microti, represents a concern for the safety of the US blood supply. STUDY DESIGN AND METHODS: This study investigated kinetics of parasitemia and innate immune responses and dynamics of antibody responses during B. microti infection in rhesus macaques (RMs) using blood smears, quantitative polymerase chain reaction (qPCR), flow cytometry, and indirect fluorescent antibody testing. A total of six monkeys were transfused with either hamster or monkey-passaged B. microti-infected red blood cells (two and four monkeys, respectively) simulating TAB. RESULTS: The prepatent period in monkeys inoculated with hamster-passaged B. microti was 35 days compared with 4 days in monkeys transfused with monkey-passaged B. microti; the latter monkeys also had markedly higher parasitemia levels. The duration of the window period from the first detected parasitemia by qPCR analysis to the first detected antibody response ranged from 10 to 17 days. Antibody responses fluctuated during the course of the infection. Innate responses assessed by the frequencies of monocytes and activated B cells correlated with the kinetics and magnitude of parasitemia. On Day 14, additional activation peaks were noted for CD14+CD16+ and CD14-CD16+ monocytes and for CD11c+ myeloid dendritic cells, but only in animals transfused with monkey-passaged B. microti. Parasitemia persisted in these immunocompetent animals, similar to human infection. CONCLUSION: The results suggest that transfusion-associated transmission of B. microti leads to rapid onset of parasitemia (Day 4) in RMs, detectable antibody response 14 days later, and persistent parasitemia.


Assuntos
Babesiose/transmissão , Macaca mulatta/imunologia , Reação Transfusional , Animais , Anticorpos Antiprotozoários/sangue , Babesiose/diagnóstico , Babesiose/imunologia , Cricetinae , Modelos Animais de Doenças , Citometria de Fluxo , Técnica Indireta de Fluorescência para Anticorpo , Haplorrinos , Cinética , Macaca mulatta/sangue , Macaca mulatta/parasitologia , Parasitemia/sangue , Parasitemia/diagnóstico , Parasitemia/transmissão , Reação em Cadeia da Polimerase
14.
Infect Immun ; 84(5): 1371-1386, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26883596

RESUMO

Infection of mammals by the parasitic helminth Schistosoma mansoni induces antibodies to glycan antigens in worms and eggs, but the differential nature of the immune response among infected mammals is poorly understood. To better define these responses, we used a shotgun glycomics approach in which N-glycans from schistosome egg glycoproteins were prepared, derivatized, separated, and used to generate an egg shotgun glycan microarray. This array was interrogated with sera from infected mice, rhesus monkeys, and humans and with glycan-binding proteins and antibodies to gather information about the structures of antigenic glycans, which also were analyzed by mass spectrometry. A major glycan antigen targeted by IgG from different infected species is the FLDNF epitope [Fucα3GalNAcß4(Fucα3)GlcNAc-R], which is also recognized by the IgG monoclonal antibody F2D2. The FLDNF antigen is expressed by all life stages of the parasite in mammalian hosts, and F2D2 can kill schistosomula in vitro in a complement-dependent manner. Different antisera also recognized other glycan determinants, including core ß-xylose and highly fucosylated glycans. Thus, the natural shotgun glycan microarray of schistosome eggs is useful in identifying antigenic glycans and in developing new anti-glycan reagents that may have diagnostic applications and contribute to developing new vaccines against schistosomiasis.


Assuntos
Antígenos de Helmintos/imunologia , Polissacarídeos/imunologia , Schistosoma mansoni/imunologia , Zigoto/imunologia , Animais , Anticorpos Anti-Helmínticos/sangue , Antígenos de Helmintos/química , Antígenos de Helmintos/isolamento & purificação , Epitopos/imunologia , Feminino , Humanos , Imunoglobulina G/sangue , Macaca mulatta , Espectrometria de Massas , Camundongos , Análise em Microsséries , Polissacarídeos/química , Polissacarídeos/isolamento & purificação , Ligação Proteica
15.
Am J Trop Med Hyg ; 94(1): 172-5, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26621562

RESUMO

We communicate a case of a middle-aged Brazilian patient with an unusual presentation of fourth ventricular neurocysticercosis: occurrence of two intraventricular cysts at different locations in the brain within 2 years and cognitive decline as the only neurological symptom. Neurocysticercosis was confirmed by magnetic resonance imaging, serology, histology, and genetic analysis. Neurocysticercosis should be considered as a differential diagnosis in cases with atypical neurologic or psychiatric symptoms, atypical neuroimaging and travel history. Especially, fourth ventricular cysts carry the risk of obstructive hydrocephalus and brainstem compression and therefore should be extirpated completely. If complete removal of the cystic structures cannot be proven in cases with surgically treated neurocysticercosis, anthelminthic therapy and thorough follow-up examinations should be conducted.


Assuntos
Quarto Ventrículo/patologia , Quarto Ventrículo/parasitologia , Neurocisticercose/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Neurocisticercose/parasitologia , Neurocisticercose/cirurgia
16.
PLoS Negl Trop Dis ; 9(12): e0004316, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26697878

RESUMO

BACKGROUND: Infections with Taenia solium are the most common cause of adult acquired seizures worldwide, and are the leading cause of epilepsy in developing countries. A better understanding of the genetic diversity of T. solium will improve parasite diagnostics and transmission pathways in endemic areas thereby facilitating the design of future control measures and interventions. Microsatellite markers are useful genome features, which enable strain typing and identification in complex pathogen genomes. Here we describe microsatellite identification and characterization in T. solium, providing information that will assist in global efforts to control this important pathogen. METHODS: For genome sequencing, T. solium cysts and proglottids were collected from Huancayo and Puno in Peru, respectively. Using next generation sequencing (NGS) and de novo assembly, we assembled two draft genomes and one hybrid genome. Microsatellite sequences were identified and 36 of them were selected for further analysis. Twenty T. solium isolates were collected from Tumbes in the northern region, and twenty from Puno in the southern region of Peru. The size-polymorphism of the selected microsatellites was determined with multi-capillary electrophoresis. We analyzed the association between microsatellite polymorphism and the geographic origin of the samples. RESULTS: The predicted size of the hybrid (proglottid genome combined with cyst genome) T. solium genome was 111 MB with a GC content of 42.54%. A total of 7,979 contigs (>1,000 nt) were obtained. We identified 9,129 microsatellites in the Puno-proglottid genome and 9,936 in the Huancayo-cyst genome, with 5 or more repeats, ranging from mono- to hexa-nucleotide. Seven microsatellites were polymorphic and 29 were monomorphic within the analyzed isolates. T. solium tapeworms were classified into two genetic groups that correlated with the North/South geographic origin of the parasites. CONCLUSIONS/SIGNIFICANCE: The availability of draft genomes for T. solium represents a significant step towards the understanding the biology of the parasite. We report here a set of T. solium polymorphic microsatellite markers that appear promising for genetic epidemiology studies.


Assuntos
Variação Genética , Genoma Helmíntico/genética , Repetições de Microssatélites/genética , Taenia solium/genética , Teníase/parasitologia , Adulto , Animais , Sequência de Bases , Mapeamento Cromossômico , DNA de Helmintos/química , DNA de Helmintos/genética , Genótipo , Geografia , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Dados de Sequência Molecular , Peru/epidemiologia , Análise de Sequência de DNA , Taenia solium/isolamento & purificação , Teníase/epidemiologia
17.
PLoS Negl Trop Dis ; 9(10): e0004168, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26485145

RESUMO

The clinical spectrum of human disease caused by the roundworms Toxocara canis and Toxocara cati ranges from visceral and ocular larva migrans to covert toxocariasis. The parasite is not typically recovered in affected tissues, so detection of parasite-specific antibodies is usually necessary for establishing a diagnosis. The most reliable immunodiagnostic methods use the Toxocara excretory-secretory antigens (TES-Ag) in ELISA formats to detect Toxocara-specific antibodies. To eliminate the need for native parasite materials, we identified and purified immunodiagnostic antigens using 2D gel electrophoresis followed by electrospray ionization mass spectrometry. Three predominant immunoreactive proteins were found in the TES; all three had been previously described in the literature: Tc-CTL-1, Tc-TES-26, and Tc-MUC-3. We generated Escherichia coli expressed recombinant proteins for evaluation in Luminex based immunoassays. We were unable to produce a functional assay with the Tc-MUC-3 recombinant protein. Tc-CTL-1 and Tc-TES-26 were successfully coupled and tested using defined serum batteries. The use of both proteins together generated better results than if the proteins were used individually. The sensitivity and specificity of the assay for detecting visceral larval migrans using Tc-CTL-1 plus Tc-TES-26 was 99% and 94%, respectively; the sensitivity for detecting ocular larval migrans was 64%. The combined performance of the new assay was superior to the currently available EIA and could potentially be employed to replace current assays that rely on native TES-Ag.


Assuntos
Anticorpos Anti-Helmínticos/sangue , Antígenos de Helmintos/imunologia , Testes Sorológicos/métodos , Toxocaríase/diagnóstico , Antígenos de Helmintos/genética , Antígenos de Helmintos/isolamento & purificação , Escherichia coli/genética , Expressão Gênica , Humanos , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/isolamento & purificação , Sensibilidade e Especificidade
18.
Trop Med Int Health ; 20(12): 1787-96, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26426162

RESUMO

OBJECTIVES: To identify immunodominant antigens of Toxocara canis recognised by Toxocara-infected sera as recombinant reagents for immunodiagnosis of toxocariasis. METHODS: Pooled sera from human cases of toxocariasis were used to identify immunodominant antigens by immunoscreening a T. canis larval expression cDNA library. The positive clones were sequenced to reveal the identity of the antigens. The recombinant proteins were expressed in E. coli and then used to confirm their immunoreaction with sera of humans with toxocariasis. Two chosen antigens were also used to differentiate Toxocara infection from other helminth infections in mice. RESULTS: Eleven antigens with immunodiagnostic potential were identified, including two C-type lectins (CTLs) that reacted strongly with the Toxocara-positive serum pool. The first CTL (Tc-CTL-1) is the same as TES-32, previously identified as a major immunodominant component of TES; the second CTL (Tc-CTL-2) is a novel C-type lectin sharing 83% amino acid sequence identity within the functional domain of Tc-CTL-1. The E. coli-expressed recombinant Tc-CTL-1 was strongly recognised by the Toxocara-positive serum pool or sera from animals experimentally infected with T. canis. Reactivity with recombinant Tc-CTL-1 was higher when the unreduced protein was used in an enzyme-linked immunosorbent assay (ELISA), dot-blot assay or Western blot test compared to the protein under reduced condition. Both recombinant Tc-CTL-1- and Tc-CTL-2-based ELISAs were able to differentiate T. canis infection from other helminth infections in experimentally infected mice. CONCLUSIONS: Both Tc-CTL-1 and Tc-CTL-2 were able to differentiate Toxocara infection from other helminth infections and could potentially be used as sensitive and specific immunodiagnostic antigens.


Assuntos
Antígenos de Helmintos/imunologia , Epitopos Imunodominantes , Toxocara canis/imunologia , Toxocaríase/diagnóstico , Sequência de Aminoácidos , Animais , Anticorpos Anti-Helmínticos/sangue , Western Blotting , Técnicas de Laboratório Clínico , DNA Complementar , Ensaio de Imunoadsorção Enzimática , Escherichia coli , Helmintíase/diagnóstico , Helmintíase/imunologia , Humanos , Larva , Lectinas/imunologia , Camundongos Endogâmicos C57BL , Proteínas Recombinantes/imunologia , Toxocaríase/imunologia
19.
Emerg Infect Dis ; 21(10): 1824-6, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26401787

RESUMO

We tested refugee camp residents on the Thailand-Myanmar border for Taenia solium infection. Taeniasis prevalence was consistent with that for other disease-endemic regions, but seropositivity indicating T. solium taeniasis was rare. Seropositivity indicating cysticercosis was 5.5% in humans, and 3.2% in pigs. Corralling pigs and providing latrines may control transmission of these tapeworms within this camp.


Assuntos
Neurocisticercose/etiologia , Prevalência , Refugiados/estatística & dados numéricos , Teníase/epidemiologia , Adolescente , Adulto , Animais , Criança , Estudos Transversais , Doenças Endêmicas , Feminino , Humanos , Masculino , Mianmar/epidemiologia , Suínos , Doenças dos Suínos/epidemiologia , Teníase/complicações , Tailândia/epidemiologia
20.
PLoS One ; 10(6): e0129097, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26053071

RESUMO

BACKGROUND: Epilepsy is one of the most common neurological conditions globally, estimated to constitute 0.75% of the global burden of disease, with the majority of this burden found in low- and middle- income countries (LMICs). Few studies from LMICs, including much of sub-Saharan Africa, have described the incidence, remission or mortality rates due to epilepsy, which are needed to quantify the burden and inform policy. This study investigates the epidemiological parameters of convulsive epilepsy within a context of high HIV prevalence and an emerging burden of cardiovascular disease. METHODS: A cross-sectional population survey of 82,818 individuals, in the Agincourt Health and Socio-demographic Surveillance Site (HDSS) in rural northeast South Africa was conducted in 2008, from which 296 people were identified with active convulsive epilepsy. A follow-up survey was conducted in 2012. Incidence and mortality rates were estimated, with duration and remission rates calculated using the DISMOD II software package. RESULTS: The crude incidence for convulsive epilepsy was 17.4/100,000 per year (95%CI: 13.1-23.0). Remission was 4.6% and 3.9% per year for males and females, respectively. The standardized mortality ratio was 2.6 (95%CI: 1.7-3.5), with 33.3% of deaths directly related to epilepsy. Mortality was higher in men than women (adjusted rate ratio (aRR) 2.6 (95%CI: 1.2-5.4)), and was significantly associated with older ages (50+ years versus those 0-5 years old (RR 4.8 (95%CI: 0.6-36.4)). CONCLUSIONS: The crude incidence was lower whilst mortality rates were similar to other African studies; however, this study found higher mortality amongst older males. Efforts aimed at further understanding what causes epilepsy in older people and developing interventions to reduce prolonged seizures are likely to reduce the overall burden of ACE in rural South Africa.


Assuntos
Epilepsia/epidemiologia , População Rural , Adolescente , Adulto , Causas de Morte , Criança , Estudos Transversais , Epilepsia/mortalidade , Feminino , Humanos , Incidência , Masculino , Mortalidade , Vigilância da População , Fatores de Risco , África do Sul/epidemiologia , Adulto Jovem
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