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1.
PeerJ ; 12: e17758, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39071132

RESUMEN

Dengue is an infectious disease caused by infection of dengue virus (DENV) transmitted by Aedes aegypti and Aedes albopictus. In Indonesia, dengue commonly occurs with an increasing incidence rate annually. It is known that early detection of dengue infection is one of the keys to controlling this disease outbreak. Rapid and accurate early detection to diagnose dengue can be achieved by molecular tests, one of which is through a real-time PCR method. However, real-time PCR assay for dengue developed based on Indonesian DENV sequences has not been available. Therefore, we developed in-house dengue real-time PCR (SYBR- and TaqMan-based) assays and evaluated those assays in routine clinical testing in the community. These assays target the 3' UTR region of the four DENV serotypes and was found to be specific for DENV. The most sensitive assay was the TaqMan assay with the LOD95% of 482 copy/ml, followed by the SYBR assay with the LOD95% of 14,398 copy/ml. We recruited dengue suspected patients from three primary health care services in West Java, Indonesia to represent the community testing setting. Dengue infection was examined using the two in-house real-time PCR assays along with NS1, IgM, and IgG rapid diagnostic tests (RDT). In total, as many as 74 clinical specimens of dengue suspected patients were included in this study. Among those patients, 21 were positive for TaqMan assay, 17 were positive for SYBR assay, nine were positive for NS1 test, six were positive for both IgG and IgM tests, and 22 were positive for IgG test only. Compared with our in-house TaqMan assay, the sensitivity of NS1 test, IgM test, and IgG test were 42.86%, 14.29%, and 28.57% respectively. Among these three RDT tests, NS1 showed 100% specificity. Thus, our study confirmed that NS1 test showed high specificity, indicating that a positive result of NS1 can be confidently considered a dengue case. However, NS1, IgM, and IgG tests with RDT are not enough to diagnose a dengue case. We suggest applying the high sensitivity and specificity rRT-PCR test as the gold standard for early detection and antibody test as a follow-up test for rRT-PCR negative cases.


Asunto(s)
Virus del Dengue , Dengue , Reacción en Cadena en Tiempo Real de la Polimerasa , Sensibilidad y Especificidad , Dengue/diagnóstico , Dengue/epidemiología , Dengue/virología , Humanos , Indonesia/epidemiología , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Virus del Dengue/genética , Virus del Dengue/aislamiento & purificación , Virus del Dengue/inmunología , Femenino , Masculino , Adulto , Adolescente , Persona de Mediana Edad , Adulto Joven , Niño , Preescolar , Anciano
2.
Lab Med ; 2023 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-37639565

RESUMEN

OBJECTIVE: This study retrospectively compared false-positive result frequencies of 3 syphilis serology screening tests and assessed whether false positivity was associated with pregnancy and age. METHODS: Results for 3 screening tests were retrieved from the laboratory database, including rapid plasma reagin (RPR) assay between October 2016 and September 2019, BioPlex 2200 Syphilis Total immunoassay between May 2020 and January 2022, and Alinity i Syphilis TP assay between February 2022 and April 2023. The false-positive result frequencies were calculated based on testing algorithm criteria. RESULTS: False-positive result frequency for BioPlex was 0.61% (90/14,707), significantly higher than 0.29% (50/17,447) for RPR and 0.38% (55/14,631) for Alinity (both P < .01). Patients with false-positive results were significantly older than patients with nonreactive results for RPR (median age: 36 vs 28, P < .001), but not for BioPlex or Alinity. For all 3 tests, the positive predictive values in pregnant women were lower than those in nonpregnant women or men. However, pregnant women did not exhibit a higher false-positive result frequency. CONCLUSION: Although false-positive result frequencies were low overall for all 3 syphilis serology tests, there is a significant difference between different tests. Pregnancy was not associated with more false-positive results for all 3 tests.

3.
Bioeng Transl Med ; 8(3): e10508, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37206248

RESUMEN

We have developed a serology test platform for identifying individuals with prior exposure to specific viral infections and provide data to help reduce public health risks. The serology test composed of a pair of cell lines engineered to express either a viral envelop protein (Target Cell) or a receptor to recognize the Fc region of an antibody (Reporter Cell), that is, Diagnostic-Cell-Complex (DxCell-Complex). The formation of an immune synapse, facilitated by the analyte antibody, resulted into a dual-reporter protein expression by the Reporter Cell. We validated it with human serum with confirmed history of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. No signal amplification steps were necessary. The DxCell-Complex quantitatively detected the target-specific immunoglobulin G (IgG) within 1 h. Validation with clinical human serum containing SARS-CoV-2 IgG antibodies confirmed 97.04% sensitivity and 93.33% specificity. The platform can be redirected against other antibodies. Self-replication and activation-induced cell signaling, two attributes of the cell, will enable rapid and cost-effective manufacturing and its operation in healthcare facilities without requiring time-consuming signal amplification steps.

4.
Smart Health (Amst) ; 26: 100331, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36281350

RESUMEN

Serology and molecular tests are the two most commonly used methods for rapid COVID-19 infection testing. The two types of tests have different mechanisms to detect infection, by measuring the presence of viral SARS-CoV-2 RNA (molecular test) or detecting the presence of antibodies triggered by the SARS-CoV-2 virus (serology test). A handful of studies have shown that symptoms, combined with demographic and/or diagnosis features, can be helpful for the prediction of COVID-19 test outcomes. However, due to nature of the test, serology and molecular tests vary significantly. There is no existing study on the correlation between serology and molecular tests, and what type of symptoms are the key factors indicating the COVID-19 positive tests. In this study, we propose a machine learning based approach to study serology and molecular tests, and use features to predict test outcomes. A total of 2,467 donors, each tested using one or multiple types of COVID-19 tests, are collected as our testbed. By cross checking test types and results, we study correlation between serology and molecular tests. For test outcome prediction, we label 2,467 donors as positive or negative, by using their serology or molecular test results, and create symptom features to represent each donor for learning. Because COVID-19 produces a wide range of symptoms and the data collection process is essentially error prone, we group similar symptoms into bins. This decreases the feature space and sparsity. Using binned symptoms, combined with demographic features, we train five classification algorithms to predict COVID-19 test results. Experiments show that XGBoost achieves the best performance with 76.85% accuracy and 81.4% AUC scores, demonstrating that symptoms are indeed helpful for predicting COVID-19 test outcomes. Our study investigates the relationship between serology and molecular tests, identifies meaningful symptom features associated with COVID-19 infection, and also provides a way for rapid screening and cost effective detection of COVID-19 infection.

5.
Methods Mol Biol ; 2511: 307-319, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35838970

RESUMEN

Severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) has been identified as the causative agent of COVID-19. Accurate detection of SARS-CoV-2 infection is not only important for management of infected individuals but also to break the chain of transmission. Although the polymerase chain reaction (PCR) is the gold standard for diagnosis of acute SARS-CoV-2 infection, there are a number of limitations of these assays, which include the inability to detect past infection and decline in sensitivity 14 days post-symptom onset. There are several serology tests developed for the detection of SARS-CoV-2 antibodies including high-throughput serology platforms and lateral flow immunoassays. These tests should be evaluated for their performance to meet local regulations acceptance criteria. To optimize the diagnostic algorithm for SARS-CoV-2, this protocol describes the evaluation of serological antibody testing using various automated serology platforms and lateral flow immunoassays. This protocol was evaluated in both serum and plasma samples. The sample preparation, procedure, and data analysis are described. The protocol can be adapted for any serological testing.


Asunto(s)
COVID-19 , SARS-CoV-2 , Anticuerpos Antivirales , COVID-19/diagnóstico , Prueba de COVID-19 , Humanos , Inmunoensayo/métodos , Sensibilidad y Especificidad
6.
Biosens Bioelectron ; 213: 114476, 2022 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-35716642

RESUMEN

Coronavirus disease 2019 (COVID-19) has caused significant global morbidity and mortality. The serology test that detects antibodies against the disease causative agent, the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has often neglected value in supporting immunization policies and therapeutic decision-making. The ELISA-based antibody test is time-consuming and bulky. This work described a gold micro-interdigitated electrodes (IDE) biosensor for COVID antibody detection based on Electrochemical Impedance Spectroscopy (EIS) responses. The IDE architecture allows easy surface modification with the viral structure protein, Spike (S) protein, in the gap of the electrode digits to selectively capture anti-S antibodies in buffer solutions or human sera. Two strategies were employed to resolve the low sensitivity issue of non-faradic impedimetric sensors and the sensor fouling phenomenon when using the serum. One uses secondary antibody-gold nanoparticle (AuNP) conjugates to further distinguish anti-S antibodies from the non-specific binding and obtain a more significant impedance change. The second strategy consists of increasing the concentration of target antibodies in the gap of IDEs by inducing an AC electrokinetic effect such as dielectrophoresis (DEP). AuNP and DEP methods reached a limit of detection of 200 ng/mL and 2 µg/mL, respectively using purified antibodies in buffer, while the DEP method achieved a faster testing time of only 30 min. Both strategies could qualitatively distinguish COVID-19 antibody-positive and -negative sera. Our work, especially the impedimetric detection of COVID-19 antibodies under the assistance of the DEP force presents a promising path toward rapid, point-of-care solutions for COVID-19 serology tests.


Asunto(s)
Técnicas Biosensibles , COVID-19 , Nanopartículas del Metal , Técnicas Biosensibles/métodos , COVID-19/diagnóstico , Electrodos , Oro/química , Humanos , Nanopartículas del Metal/química , SARS-CoV-2
7.
Bioeng Transl Med ; 7(2): e10293, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35600666

RESUMEN

There is clinical need for a quantifiable point-of-care (PoC) SARS-CoV-2 neutralizing antibody (nAb) test that is adaptable with the pandemic's changing landscape. Here, we present a rapid and semi-quantitative nAb test that uses finger stick or venous blood to assess the nAb response of vaccinated population against wild-type (WT), alpha, beta, gamma, and delta variant RBDs. It captures a clinically relevant range of nAb levels, and effectively differentiates prevaccination, post first dose, and post second dose vaccination samples within 10 min. The data observed against alpha, beta, gamma, and delta variants agrees with published results evaluated in established serology tests. Finally, our test revealed a substantial reduction in nAb level for beta, gamma, and delta variants between early BNT162b2 vaccination group (within 3 months) and later vaccination group (post 3 months). This test is highly suited for PoC settings and provides an insightful nAb response in a postvaccinated population.

8.
Sensors (Basel) ; 21(19)2021 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-34640901

RESUMEN

Population-scale and rapid testing for SARS-CoV-2 continues to be a priority for several parts of the world. We revisit the in vitro technology platforms for COVID-19 testing and diagnostics-molecular tests and rapid antigen tests, serology or antibody tests, and tests for the management of COVID-19 patients. Within each category of tests, we review the commercialized testing platforms, their analyzing systems, specimen collection protocols, testing methodologies, supply chain logistics, and related attributes. Our discussion is essentially focused on test products that have been granted emergency use authorization by the FDA to detect and diagnose COVID-19 infections. Different strategies for scaled-up and faster screening are covered here, such as pooled testing, screening programs, and surveillance testing. The near-term challenges lie in detecting subtle infectivity profiles, mapping the transmission dynamics of new variants, lowering the cost for testing, training a large healthcare workforce, and providing test kits for the masses. Through this review, we try to understand the feasibility of universal access to COVID-19 testing and diagnostics in the near future while being cognizant of the implicit tradeoffs during the development and distribution cycles of new testing platforms.


Asunto(s)
Prueba de COVID-19 , COVID-19 , Humanos , Tamizaje Masivo , SARS-CoV-2 , Tecnología
9.
Appl Microbiol Biotechnol ; 105(18): 6547-6557, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34448897

RESUMEN

Rabies is an ancient fatal disease with no other available treatment than post-exposure vaccination, where the bite of infected animals, mainly dogs, is the leading cause of its transmission to human beings. In this context, global vaccination campaigns of companion animals, as well as wildlife reservoirs vaccination, are key factors to achieve the "Zero by 30" plan that pursues the eradication of dog-mediated human rabies by 2030. Rabies virus-neutralizing antibodies (VNAs) play an essential role in the disease protection, as it correlates with an adequate immune response and allows evaluating pre- or post-exposure prophylaxis efficacy. Hence, counting with reliable, accurate, and robust serological tests is of paramount importance. Currently, RFFIT and FAVN are the gold standard VNAs tests recommended by both the WHO and the OIE. Despite these methodologies are efficient and widely used, they present several drawbacks, as they are less easily to standardize and require the use of live rabies virus, containment facilities, and skilled professionals. Thus, in this review, we describe the state-of-the-art of alternative analytical methodologies currently available for rabies serology, with novel approaches based on pseudotyped recombinant viruses and emphasizing in the antigen binding methodologies that detect and quantify antibodies against the rabies glycoprotein. We discussed the wide range of assays that are interesting tools for a faster measurement of anti-rabies glycoprotein antibodies and, in some cases, less complex and more versatile than the gold standard methods. Finally, we discussed the key issues during the design and optimization steps of ELISA assays, highlighting the importance of validation and standardization procedures to improve rabies serology tests and, as a consequence, their results. KEY POINTS: • An exhaustive revision of rabies serology testing was made. • No rabies serology assay can be thought as better than others for all intents and purposes. • The validation procedure guarantees reliable and consistent results among the globe.


Asunto(s)
Vacunas Antirrábicas , Virus de la Rabia , Rabia , Animales , Anticuerpos Antivirales , Perros , Glicoproteínas , Pruebas de Neutralización , Rabia/prevención & control , Rabia/veterinaria
10.
Wien Klin Wochenschr ; 133(17-18): 923-930, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33835265

RESUMEN

BACKGROUND: Chronic kidney disease patients show a high mortality in cases of a severe acute respiratory syndrome coronavirus-2 (SARS-CoV­2) infection. Thus, information on the sero-status of nephrology personnel might be crucial for patient protection; however, limited information exists about the presence of SARS-CoV­2 antibodies in asymptomatic individuals. METHODS: We examined the seroprevalence of SARS-CoV­2 IgG and IgM antibodies among healthcare workers of a tertiary care kidney center during the the first peak phase of the corona virus disease 2019 (COVID-19) crisis in Austria using an orthogonal test strategy and a total of 12 commercial nucleocapsid protein or spike glycoprotein-based assays as well as Western blotting and a neutralization assay. RESULTS: At baseline 60 of 235 study participants (25.5%, 95% confidence interval, CI 20.4-31.5%) were judged to be borderline positive or positive for IgM or IgG using a high sensitivity/low specificity threshold in one test system. Follow-up analysis after about 2 weeks revealed IgG positivity in 12 (5.1%, 95% CI: 2.9-8.8%) and IgM positivity in 6 (2.6%, 95% CI: 1.1-5.6) in at least one assay. Of the healthcare workers 2.1% (95% CI: 0.8-5.0%) showed IgG nucleocapsid antibodies in at least 2 assays. By contrast, positive controls with proven COVID-19 showed antibody positivity among almost all test systems. Moreover, serum samples obtained from healthcare workers did not show SARS-CoV­2 neutralizing capacity, in contrast to positive controls. CONCLUSION: Using a broad spectrum of antibody tests the present study revealed inconsistent results for SARS-CoV­2 seroprevalence among asymptomatic individuals, while this was not the case among COVID-19 patients. TRIAL REGISTRATION NUMBER: CONEC, ClinicalTrials.gov number NCT04347694.


Asunto(s)
COVID-19 , Nefrología , Anticuerpos Antivirales , Personal de Salud , Humanos , SARS-CoV-2 , Estudios Seroepidemiológicos
11.
Comp Immunol Microbiol Infect Dis ; 73: 101554, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32979614

RESUMEN

Canine brucellosis is a contagious disease associated with health implications for humans as well as for a wide range of wild and domesticated animals. In this study, 173 dog blood specimens were sampled from herding dogs in three different provinces including Tehran (n = 127), Qom (n = 40) and Alborz (n = 6) provinces. The presence of Brucella antibodies was determined using Rose Bengal plate test (RBPT), slow agglutination test (SAT) and 2-mercaptoethanol (2-ME), respectively. The seropositive samples were further screened using blood culture and PCR tests to identify and differentiate the implicated Brucella species. According to our results, 24.3% (42/173), 13.8% (24/173) and 6.3% (11/173) of blood samples were tested positive using RBPT, SAT and 2-ME, respectively. However, among 42 seropositive samples, only 38.1% (16/42) and 14.2% (6/42) were positive by PCR and culture, respectively. Brucella melitensis biovar 1 and biovar 2 was isolated from the bacterial cultures of 6 blood samples and confirmed by biotyping, AMOS PCR and Bruce-ladder PCR assays. These findings highlight the potential risk of Brucella transmission from dog to humans along with other livestock and reflect the critical role of infected dogs in the persistence of Brucella infections among ruminant farms. This study stresses the need for further epidemiological investigations on canine brucellosis among herding dogs and suggests the systematic screening of the disease among companion animals such as dogs in order to improve brucellosis surveillance and control programs.


Asunto(s)
Brucella melitensis , Brucelosis/veterinaria , Enfermedades de los Perros/microbiología , Animales , Anticuerpos Antibacterianos/sangre , Brucella melitensis/inmunología , Brucelosis/diagnóstico , Brucelosis/epidemiología , Brucelosis/prevención & control , Enfermedades de los Perros/diagnóstico , Enfermedades de los Perros/epidemiología , Perros , Granjas , Irán , Rumiantes
12.
Pan Afr Med J ; 36: 80, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32774639

RESUMEN

The coronavirus disease (COVID-19) caused by the novel severe acute respiratory syndrome coronavirus 2 (SARS-COV-2) has become a pandemic. There is currently no vaccine or effective treatment for COVID-19. Early diagnosis and management is key to favourable outcomes. In order to prevent more widespread transmission of the virus, rapid detection and isolation of confirmed cases is of utmost importance. Real time reverse transcriptase polymerase chain reaction (RT-PCR) is currently the "gold standard" for the detection of SARS-COV-2. There are several challenges associated with this test from sample collection to processing and the longer turnaround time for the results to be available. More rapid and faster diagnostic tests that may produce results within minutes to a few hours will be instrumental in controlling the disease. Serological tests that detect specific antibodies to the virus may be such options. In this review, we extensively searched for studies that compared RT-PCR with serological tests for the diagnosis of COVID-19. We extracted the data from the various selected studies that compared the different tests and summarised the available evidence to determine which test is more appropriate especially in Africa. We also reviewed the current evidence and the challenges for the genome sequencing of SARS-COV-2 in Africa. Finally, we discuss the relevance of the different diagnostic tests and the importance of genome sequencing in identifying potential therapeutic options for the control of COVID-19 in Africa.


Asunto(s)
Técnicas de Laboratorio Clínico , Infecciones por Coronavirus/diagnóstico , Genoma Humano , Neumonía Viral/diagnóstico , África/epidemiología , Betacoronavirus/aislamiento & purificación , COVID-19 , Prueba de COVID-19 , Vacunas contra la COVID-19 , Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/genética , Humanos , Pandemias , Neumonía Viral/epidemiología , Neumonía Viral/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , SARS-CoV-2 , Pruebas Serológicas , Factores de Tiempo
13.
Cell Rep Med ; 1(3): 100040, 2020 06 23.
Artículo en Inglés | MEDLINE | ID: mdl-32835303

RESUMEN

SARS-CoV-2, the virus responsible for COVID-19, is causing a devastating worldwide pandemic, and there is a pressing need to understand the development, specificity, and neutralizing potency of humoral immune responses during acute infection. We report a cross-sectional study of antibody responses to the receptor-binding domain (RBD) of the spike protein and virus neutralization activity in a cohort of 44 hospitalized COVID-19 patients. RBD-specific IgG responses are detectable in all patients 6 days after PCR confirmation. Isotype switching to IgG occurs rapidly, primarily to IgG1 and IgG3. Using a clinical SARS-CoV-2 isolate, neutralizing antibody titers are detectable in all patients by 6 days after PCR confirmation and correlate with RBD-specific binding IgG titers. The RBD-specific binding data were further validated in a clinical setting with 231 PCR-confirmed COVID-19 patient samples. These findings have implications for understanding protective immunity against SARS-CoV-2, therapeutic use of immune plasma, and development of much-needed vaccines.

14.
J Vet Med Sci ; 82(3): 325-332, 2020 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-31996495

RESUMEN

Among domestic animals, melioidosis is one of the most common diseases reported in goat, sheep, and swine. To evaluate the specific antibodies in goats with melioidosis, we developed a serology test using recombinant outer membrane protein A (OmpA) and flagellin (FliC) of Burkholderia pseudomallei as antigens. DNA corresponding to each antigen was cloned into a pET32a vector and expressed in Escherichia coli. Essentially, the recombinant OmpA and FliC were expressed in a soluble form that could be isolated with 95% homogeneity. Both recombinants could be recognized by rabbit antibodies prepared against heat-inactivated B. pseudomallei (1:1,000) on a Western blot. Subsequently, we demonstrated that both recombinants could capture the antibodies present in goat with naturally occurring melioidosis (optimized titer 1:40) while not cross-reacting with the serum samples of goats naturally infected by Corynebacterium pseudotuberculosis or Staphylococcus aureus. Finally, an enzyme-linked immunosorbent assay (ELISA) using 20 goat serum samples without melioidosis and 10 goat serum samples with melioidosis demonstrated that the infected group has significantly higher antibody titer levels than the normal group (P<0.001) when using either OmpA or FliC as an antigen. However, the sensitivity (100%) of the assay using OmpA was superior to that (90%) from using FliC. Serological tests that are commonly used often rely on antigens from crude cell extracts, which pose risks for laboratory-acquired infections and inconsistency in their preparation; however, use of recombinant OmpA is safe; it can potentially be used as a reagent in testing for goat melioidosis.


Asunto(s)
Proteínas de la Membrana Bacteriana Externa/inmunología , Burkholderia pseudomallei/inmunología , Flagelina/inmunología , Enfermedades de las Cabras/diagnóstico , Melioidosis/veterinaria , Animales , Anticuerpos Antibacterianos/sangre , Ensayo de Inmunoadsorción Enzimática/veterinaria , Enfermedades de las Cabras/sangre , Cabras , Inmunoensayo , Melioidosis/diagnóstico , Melioidosis/inmunología , Proteínas Recombinantes/inmunología , Sensibilidad y Especificidad , Pruebas Serológicas/veterinaria
16.
Front Immunol ; 9: 1690, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30090101

RESUMEN

In Brazil, canine visceral leishmaniasis (CVL) is caused by Leishmania infantum, presenting a broad spectrum of clinical manifestations. Dogs are the main parasite reservoir in urban areas and canine cases precede human infection. Currently, A2 protein based Leish-Tec® vaccine is the only vaccine commercially available against CVL in Brazil. Considering that the main screening and confirmatory tests of canine infection are serological, it is possible that the antibody response elicited after vaccination interfere with diagnosis, leading to the inability to distinguish between vaccinated and infected animals. In order to identify the specific B-cell response induced after vaccination, A2 protein sequence was screened for main linear B-cell epitopes using in silico prediction (Bepipred) and immunological confirmation by ELISA. Three amino acid sequences were described as potential B-cell epitopes (SV11-SAEPHKAAVDV, PP16-PQSVGPLSVGPQSVGP, and VQ34-VGPLSVGPQSVGPLSVGPLSVGPQAVGPLSVGPQ). Specific IgG ELISAs were performed in sera of 12 immunized dogs living in non-endemic areas, followed for up to 1 year after immunization. The results were compared with those obtained in a group of 10 symptomatic and 10 asymptomatic CVL dogs. All predicted epitopes were confirmed as linear B-cell epitopes broadly recognized by sera from studied dogs. Total IgG ELISAs demonstrated distinct patterns of response between peptides in the immunized and CVL groups. VQ34 peptide was recognized by the majority of sera from vaccinated and symptomatic dogs, and increases after vaccination. PP16 induced low levels of specific IgG that increased 1 year after immunization. Interestingly, a low frequency of reactivity was found against SV11 in naturally infected dogs (symptomatic and asymptomatic), while 83.3% of vaccinated dogs presented positive responses 1 year after immunization. The two animals in the vaccinated group that did not respond to SV11 1 year after immunization presented positive serology both 30 days and 6 months after immunization. In summary, we identified three main linear B-cell epitopes in A2 based vaccine. Moreover, the humoral response against SV11 presented marked differences between infected and Leish-Tec vaccinated dogs, and should be further investigated, in large trials, to confirm its potential as a serological marker able to distinguish between infected and vaccinated dogs.

17.
Pan Afr Med J ; 26: 221, 2017.
Artículo en Francés | MEDLINE | ID: mdl-28690735

RESUMEN

INTRODUCTION: Malaria serology test seems to have attracted very little interest in endemic countries such as Ivory Coast. However, this examination has been regularly performed in the parasitology laboratory at the Training and Research Unit of Medical Sciences in Abidjan. Our study aimed to highlight the contribution of malaria serology test in our endemic country context. METHODS: We conducted a retrospective study of malaria serology test using Falciparum-Spot IF (bioMerieux) kit for the detection of IgG antiplasmodial antibodies. It included all malaria serology tests performed from January 2007 to February 2011 and whose results were available in the registry. RESULTS: In total, 136 patients were selected. The average age of patients was 36,3 years, ranging from 1 to 81 years, and sex ratio was 0,97. Indications for malaria serology test were varied and dominated by splenomegaly (49.3%), cytopenias (14.7%), indeterminate fever (13.2%). Almost all of the patients (98.5%) had antiplasmodial antibodies with high medium titer of 1057,35IU/ml. There was no link between age and Ab titer, which was higher in cytopenias, prolonged fevers and the splenomegaly. CONCLUSION: Malaria serology test seems to have attracted very little interest in routine clinical practice provided in our endemic area because, whatever the reason of the prescription, titers were high.


Asunto(s)
Malaria Falciparum/diagnóstico , Plasmodium falciparum/inmunología , Pruebas Serológicas/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Anticuerpos Antiprotozoarios/inmunología , Niño , Preescolar , Côte d'Ivoire/epidemiología , Femenino , Fiebre/epidemiología , Fiebre/parasitología , Humanos , Inmunoglobulina G/inmunología , Lactante , Malaria Falciparum/epidemiología , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Esplenomegalia/epidemiología , Esplenomegalia/parasitología , Adulto Joven
18.
Expert Rev Anti Infect Ther ; 13(3): 327-42, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25641365

RESUMEN

West Nile virus (WNV) is a mosquito-borne flavivirus responsible for an increasing number of human outbreaks of neuroinvasive disease in Europe and in North America. Notwithstanding the improvements in the knowledge of virus epidemiology and clinical course of infection and the development of new laboratory tests, the diagnosis of WNV infection remains challenging and many cases still remain unrecognized. WNV genome diversity, transient viremia with low viral load and cross-reactivity with other flaviviruses of the antibodies induced by WNV infection are important hurdles that require the diagnosis to be performed by experienced laboratories. Herein, we present and discuss the novel findings on the molecular epidemiology and clinical features of WNV infection in humans with special focus on Europe, the performance of diagnostic tests and the novel methods that have been developed for the diagnosis of WNV infection. A view on how the field might evolve in the future is also presented.


Asunto(s)
Fiebre del Nilo Occidental/diagnóstico , Fiebre del Nilo Occidental/epidemiología , Fiebre del Nilo Occidental/inmunología , Virus del Nilo Occidental/genética , Anticuerpos Antivirales/sangre , Afinidad de Anticuerpos , Reacciones Cruzadas , Brotes de Enfermedades , Europa (Continente) , Humanos , Pruebas de Neutralización , América del Norte , Pruebas Serológicas , Carga Viral , Virus del Nilo Occidental/aislamiento & purificación
19.
Gastroenterology ; 147(3): 610-617.e1, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24837306

RESUMEN

BACKGROUND & AIMS: We investigated whether screen-detected and apparently asymptomatic adults with endomysial antibodies (EmA) benefit from a gluten-free diet (GFD). METHODS: We performed a prospective trial of 3031 individuals at risk for celiac disease based on screens for EmA. Of 148 seropositive individuals, 40 fulfilled inclusion criteria and were assigned randomly to groups placed on a GFD or gluten-containing diets. We evaluated ratios of small-bowel mucosal villous height:crypt depth, serology and laboratory test results, gastrointestinal symptom scores, physiologic well-being, perception of health by a visual analog scale, bone mineral density, and body composition at baseline and after 1 year. Thereafter, the group on the gluten-containing diet started a GFD and was evaluated a third time; subjects in the GFD group remained on this diet. RESULTS: After 1 year on the GFD, the mean mucosal villous height:crypt depth values increased (P < .001), levels of celiac-associated antibodies decreased (P < .003), and gastrointestinal symptoms improved to a greater extent than in patients on gluten-containing diets (P = .003). The GFD group also had reduced indigestion (P = .006), reflux (P = .05), and anxiety (P = .025), and better health, based on the visual analog scale (P = .017), than the gluten-containing diet group. Only social function scores improved more in the gluten-containing diet group than in the GFD group (P = .031). There were no differences between groups in laboratory test results, bone mineral density, or body composition. Most measured parameters improved when patients in the gluten-containing diet group were placed on GFDs. No subjects considered their experience to be negative and most expected to remain on GFDs. CONCLUSIONS: GFDs benefit asymptomatic EmA-positive patients. The results support active screening of patients at risk for celiac disease. Clinicaltrials.gov no: NCT01116505.


Asunto(s)
Autoanticuerpos/sangre , Enfermedad Celíaca/dietoterapia , Dieta Sin Gluten , Pruebas Serológicas , Transglutaminasas/inmunología , Adulto , Anciano , Enfermedades Asintomáticas , Biomarcadores/sangre , Composición Corporal , Densidad Ósea , Enfermedad Celíaca/sangre , Enfermedad Celíaca/diagnóstico , Enfermedad Celíaca/genética , Enfermedad Celíaca/inmunología , Femenino , Finlandia , Proteínas de Unión al GTP , Antígenos HLA-DQ/genética , Humanos , Mucosa Intestinal/inmunología , Mucosa Intestinal/patología , Intestino Delgado/inmunología , Intestino Delgado/patología , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Prospectivos , Proteína Glutamina Gamma Glutamiltransferasa 2 , Calidad de Vida , Factores de Tiempo , Resultado del Tratamiento , Adulto Joven
20.
Vet Dermatol ; 9(3): 201-205, 1998 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34644945

RESUMEN

This study evaluated a new perspective in the diagnosis of dermatitis in dogs with signs suggestive of allergic skin disease. The results obtained with CMG IMMUNODOT tests using the technique of allergen-specific strip tests, as employed for human allergy diagnosis, were compared with those obtained by the intradermal skin test (IDST). Forty-eight cases completed the diagnostic evaluation, which included IDST, flea-control program, exclusion of sarcoptes and, for some cases, a 1- to 2-month stabilization period on a restricted protein source diet and testing the serum in the presence of allergen-specific IgE and total IgE. The most common disorders included house and storage dust mites, allergic dermatitis and flea-allergic dermatitis together with atopy. This was confirmed serologically. In the case of positive IDST to pollens, Aspergillus spp. and cat epithelium, CMG IMMUNODOT strip tests were negative. A total of 25% of cases were considered to be primarily associated with food hypersensitivity, but only 4% were confirmed serologically. This study emphasizes the value of CMG IMMUNODOT tests as a support in the diagnosis of dog allergy.

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