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1.
PLoS Negl Trop Dis ; 15(4): e0009228, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33844691

RESUMO

Crimean-Congo hemorrhagic fever virus (CCHFV) is one of the most widespread zoonotic arthropod-borne viruses in many parts of Africa, Europe and Asia. It belongs to the family of Nairoviridae in the genus of Orthonairovirus. The main reservoir and vector are ticks of the genus Hyalomma. Livestock animals (such as cattle, small ruminants and camels) develop a viremias lasting up to two weeks with absence of clinical symptoms, followed by seroconversion. This study was carried out to assess risk factors that affect seroprevalence rates in different species. In total, 928 livestock animal samples (cattle = 201; sheep = 247; goats = 233; camels = 247) from 11 out of 13 regions in Mauritania were assayed for CCHFV-specific immunoglobulin G (IgG) antibodies using enzyme-linked immunosorbent assays (ELISA) (including a novel indirect camel-IgG-specific CCHFV ELISA). Inconclusive results were resolved by an immunofluorescence assay (IFA). A generalized linear mixed-effects model (GLMM) was used to draw conclusions about the impact of certain factors (age, species, sex and region) which might have influenced the CCHFV antibody status of surveyed animals. In goats and sheep, about 15% of the animals were seropositive, whereas in cattle (69%) and camels (81%), the prevalence rate was significantly higher. On average, cattle and camels were up to twice to four times older than small ruminants. Interestingly, the seroprevalence in all species was directly linked to the age of the animals, i.e. older animals had significantly higher seroprevalence rates than younger animals. The highest CCHFV seroprevalence in Mauritania was found in camels and cattle, followed by small ruminants. The large proportion of positive animals in cattle and camels might be explained by the high ages of the animals. Future CCHFV prevalence studies should at least consider the age of surveyed animals in order to avoid misinterpretations.


Assuntos
Anticorpos Anti-Idiotípicos/análise , Vírus da Febre Hemorrágica da Crimeia-Congo/imunologia , Febre Hemorrágica da Crimeia/diagnóstico , Carrapatos/virologia , Animais , Camelus , Bovinos , Ensaio de Imunoadsorção Enzimática , Feminino , Imunofluorescência , Cabras , Vírus da Febre Hemorrágica da Crimeia-Congo/isolamento & purificação , Febre Hemorrágica da Crimeia/virologia , Gado/sangue , Gado/parasitologia , Masculino , Mauritânia , Estudos Soroepidemiológicos , Ovinos
2.
Transfusion ; 61(4): 1080-1092, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33629748

RESUMO

BACKGROUND: We hypothesized that variability in practice exists for newborn immunohematology testing due to lack of consensus guidelines. We report the results of a survey assessing that variability at hospitals in the United States and Canada. STUDY DESIGN AND METHODS: An AABB Pediatric Subsection working party developed and validated a survey of newborn immunohematology testing practice. The survey was sent electronically to transfusion service leadership at teaching institutions. RESULTS: The response rate was 67% (61/91); 56 surveys meeting inclusion criteria were analyzed. Approximately 90% (50/56) were from birth hospitals and 16.1% (9/56) were from pediatric hospitals. Newborn immunohematology testing is ordered as a panel by 66.0% (33/50) of birth hospitals. ABO group and DAT is mandated before discharge in 14/56 (25.0%) and 13/56 (23.2%), respectively. About 76.8% (43/56) selectively perform a DAT according to blood blank or clinical parameters. The most common DAT practices include anti-IgG only testing by 73.2% (41/56) and use of umbilical cord specimen type by 67.9% (38/56). A positive DAT is a critical value for 26.8% (15/56) and followed with eluate testing when a maternal antibody screen is positive for 48.2% (27/56). In the setting of a non-ABO maternal red cell antibody, 55.4% (31/56), phenotype neonatal red cells when the DAT is positive. Group O RBC are transfused irrespective of the DAT result for 82.1%, (46/56). CONCLUSION: There is variability in newborn immunohematology testing and transfusion practice and potential overutilization of the DAT. Evidence-based consensus guidelines should be developed to standardize practice and to improve safety.


Assuntos
Teste de Coombs/estatística & dados numéricos , Eritroblastose Fetal/imunologia , Recém-Nascido/imunologia , Medicina Transfusional/normas , Sistema ABO de Grupos Sanguíneos/imunologia , Anticorpos Anti-Idiotípicos/análise , Bilirrubina/análise , Canadá/epidemiologia , Teste de Coombs/normas , Eritroblastose Fetal/diagnóstico , Eritroblastose Fetal/epidemiologia , Eritrócitos/imunologia , Sangue Fetal/imunologia , Sangue Fetal/metabolismo , Humanos , Hiperbilirrubinemia/sangue , Hiperbilirrubinemia/diagnóstico , Lactente , Recém-Nascido/sangue , Guias de Prática Clínica como Assunto/normas , Prevalência , Estudos Retrospectivos , Inquéritos e Questionários , Estados Unidos/epidemiologia
3.
Biosens Bioelectron ; 160: 112215, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32339156

RESUMO

Chemiluminescence-enzyme immunoassays make it possible to measure trace components with high sensitivity and selectivity due to the high specificity of the antigen-antibody reaction and the high sensitivity of chemiluminescence assays. However, using an enzyme-labeled antibody suffers from many problems such as low reproducibility due to the instability of the enzyme and inhibition of antigen-antibody reaction due to its steric effect. Therefore, herein we report an innovative non-enzymatic chemiluminescence immunoassays labeling reagent through using quinone as a signal-generating tag coupled with biotin as a binder, to overcome enzymatic labeling problems. Biotinylated-1,4-naphthoquinone (biotin-NQ) was synthesized and characterized and it could produce long-lasting chemiluminescence upon mixing with dithiothreitol and luminol based on the redox cycle of quinone. Biotin-NQ showed exceptional stability towards different stress factors that may be encountered during performing the immunoassay such as high temperatures, highly acidic and alkaline conditions, and repeated freeze-thaw cycles. On the other hand, all these conditions lead to decreased labeling enzyme reactivity due to possible denaturation of its protein structure. Finally, the measurement of the biotin-labeled antibody was successfully performed using biotin-NQ and avidin. As a result, the antibody could be detected down to 25.7 nM which is 2.5 times sensitive than biotin-HRP chemiluminescence-enzyme immunoassays. Moreover, our method was applied successfully for determination of avidin using immobilized biotinylated antibody and biotin-NQ, which simulates immunoassays. Avidin could be detected down to 23.4 nM with excellent linearity (r = 0.996). Accordingly, our developed reagent, biotin-NQ, could be used as a universal highly stable, cost-effective, and steric free non-enzymatic label for immunoassays.


Assuntos
Anticorpos Anti-Idiotípicos/análise , Substâncias Luminescentes/química , Naftoquinonas/química , Animais , Avidina/química , Técnicas Biossensoriais/métodos , Biotina/química , Biotinilação , Imunoensaio/métodos , Medições Luminescentes/métodos , Coelhos
4.
Anal Bioanal Chem ; 412(8): 1901-1914, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32030491

RESUMO

Immunoglobin E (IgE)-related allergy constitutes a high proportion in allergic diseases. The production of specific IgE is key to evoking serial cascades and pathological reactions. Thus, targeting IgE is a different therapeutic approach from symptomatic treatments. Monoclonal antibodies (mAbs) against IgE were developed and a humanized antibody, omalizumab, was approved by five countries. It could inhibit the binding of IgE with epsilon receptor I of crystallizable fragment (FcεRI), thus preventing anaphylactic reactions. However, no bioactivity assay, which is the critical quality attribute and should thoroughly reflect the clinical mechanism, has been established to date. In commercial lot release, only the enzyme-linked immunosorbent assay (ELISA) method was applied, which only reflects the binding of omalizumab to IgE but not the subsequent reaction. In scientific research works, human FcεRI-transfected RBL-2H3 cells were used to indicate degranulation based on the detection of ß-hexosaminidase. Nevertheless, this method needs much work to stabilize the response and, hence, is not suitable for routine usage in commercial production and control of antibodies. To evaluate the bioactivity of anti-IgE antibodies including omalizumab using a simple assay that reflects the following mechanism of actions (MOA) after binding, we established an RBL-2H3 cell line transfected with both the α subunit of human FcεRI and nuclear factor-activated T cell (NFAT) response elements, the latter is conjugated with a luciferase gene, which could shed luminescence when substrates exist. The method was proven to possess good specificity, accuracy, linearity, and precision and may be utilized as a supplement to anti-IgE antibody bioactivity assays in terms of development, lot release, stability, and comparability studies. Graphical abstract The mechanism sketch of reporter gene assay for bioactivity determination of anti-IgE antibodies by RBL-2H3/FcεRIα/NFAT-Luc cells (left) and representative curves generated by the reporter gene assay (right).


Assuntos
Anticorpos Anti-Idiotípicos/análise , Bioensaio/métodos , Genes Reporter , Animais , Linhagem Celular Tumoral , Ensaio de Imunoadsorção Enzimática , Humanos
5.
J Immunol Methods ; 479: 112736, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31917969

RESUMO

The recent identification of human monoclonal antibodies with broad and potent neutralizing activity against HIV-1 (bnAbs) has resulted in substantial efforts to develop these molecules for clinical use in the prevention and treatment of HIV-1 infection. As with any protein therapeutic drug product, it is imperative to have qualified assays that can accurately detect and quantify anti-drug antibodies (ADA) that may develop in patients receiving passive administration of HIV-1 bnAbs. Here, we have optimized and qualified a functional assay to assess the potential of ADA to inhibit the neutralizing function of HIV-1 bnAbs. Using a modified version of the validated TZM-bl HIV-1 neutralization assay, murine anti-idiotype antibodies were utilized to optimize and evaluate parameters of linearity, range, limit of detection, specificity, and precision for measuring inhibitory ADA activity against multiple HIV-1 bnAbs that are in clinical development. We further demonstrate the utility of this assay for detecting naturally occurring ADA responses in non-human primates receiving passive administration of human bnAbs. This functional assay format complements binding-antibody ADA strategies being developed for HIV-1 bnAbs, and when utilized together, will support a multi-tiered approach for ADA testing that is compliant with Good Clinical Laboratory Practice (GCLP) procedures and FDA guidance.


Assuntos
Anticorpos Anti-Idiotípicos/análise , Anticorpos Monoclonais Murinos/análise , Anticorpos Amplamente Neutralizantes/uso terapêutico , Anticorpos Anti-HIV/uso terapêutico , Infecções por HIV/terapia , HIV-1/fisiologia , Testes de Neutralização/métodos , Animais , Anticorpos Amplamente Neutralizantes/imunologia , Anticorpos Anti-HIV/imunologia , Humanos , Camundongos
6.
J Clin Rheumatol ; 26(1): 19-23, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30273262

RESUMO

BACKGROUND AND OBJECTIVE: Primary Sjögren syndrome (pSS) is a systemic autoimmune rheumatic disease that particularly affects exocrine glands. Dry eye is one of the most important features of this syndrome, and a recent study reported reduced deoxyribonuclease I (DNase I) activity in the tear of patients with dry eye. We therefore postulated that patients with pSS might have antibodies targeting DNAse I. METHODS: We have evaluated in a cross-sectional study 85 patients with pSS (2002 American-European Consensus Group Criteria), 50 rheumatoid arthritis (RA) patients (1987 American College of Rheumatology Criteria) without sicca symptoms, and 88 healthy volunteers. IgG anti-DNase I was detected by enzyme-linked immunosorbent assay using as antigen bovine pancreas enzyme and confirmed by immunoblotting. RESULTS: Age and sex were alike in the 3 groups (p > 0.05). Anti-DNase I was detected in 43.5% of the pSS patients. In contrast, this reactivity was absent in all RA patients (p = 0.0001). Additional comparison of pSS patients with (n = 37) or without (n = 48) anti-DNase I showed that the former group had higher IgG serum levels (2293.2 ± 666.2 vs 1483.9 ± 384.6 mg/dL, p = 0.0001) and greater rate of non-drug-induced leukopenia (43% vs 19%, p = 0.02). A multivariate logistic regression analysis identified that only IgG levels were independently associated with anti-DNase I. CONCLUSIONS: We describe a high frequency of anti-DNase I antibodies in pSS patients associated with higher serum IgG levels. The lack of this reactivity in RA patients without sicca symptoms suggests that this antibody may be helpful in the differential diagnosis of these diseases.


Assuntos
Anticorpos Anti-Idiotípicos/imunologia , Autoanticorpos/imunologia , Desoxirribonuclease I/imunologia , Síndromes do Olho Seco/diagnóstico , Imunoglobulina G/sangue , Síndrome de Sjogren/imunologia , Adulto , Fatores Etários , Anticorpos Anti-Idiotípicos/análise , Doenças Autoimunes/diagnóstico , Estudos Transversais , Síndromes do Olho Seco/imunologia , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Humanos , Incidência , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Prognóstico , Medição de Risco , Índice de Gravidade de Doença , Fatores Sexuais , Síndrome de Sjogren/fisiopatologia
7.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 35(8): 750-756, 2019 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-31638573

RESUMO

Objective To prepare and characterize the somatostatin (SS) anti-idiotypic antibody of yolk (SS yolk Ab2 ) on the basis of successful preparation of neutralizing SS mAb1 2E7, and then to further probe the application of SS yolk Ab2 in promoting animal growth. Methods The egg-laying hens were immunized with the neutralizing SS mAb1 2E7. The eggs containing a high titer of SS yolk Ab2 were collected and the egg yolk was separated from the egg white. The SS yolk Ab2 in yolk solution was extracted by water dilution and acidification, and was purified by precipitating with cool ethanol. The titer, concentration and specificity of SS yolk Ab2 was determined by ELISA. The Ab2ß property of SS yolk Ab2 was determined by ELISA of competitive inhibition. The effect of SS yolk Ab2 on animal growth was experimented in the mice, chickens and fish. Results The SS yolk Ab2 had a titer of 1×10-5 and a concentration of 8 mg/mL. The SS yolk Ab2 could react with the rabbit antibody against SS, but not react with the rabbit antibody against growth hormone, insulin and gastrin. The immunoreaction between the SS yolk Ab2 and rabbit antibody against SS was inhibited by SS competitively. The SS yolk Ab2 could induce the mouse to produce SS Ab3 and the SS Ab3 could react with SS, which suggest that the SS yolk Ab2 was an Ab2ß. The SS yolk Ab2 was used to immunize the mice in different doses of 0.8 µg or 3.2 µg each mouse by subcutaneous injection, and to immunize the chickens in different doses of 0.8 µg or 3.2 µg each chicken through intramuscular injection, and to immunize the Doppelfish in doses of 3.2 µg each Doppelfish by immersing fishes in 2 L of sea water containing Ab2. The control animals were immunized with the same volume of physiological saline and by the same methods. One month later, the SS yolk Ab2 vaccine could increase body weight 33.5% and 37.0% in the mice, 25.6% and 34.1% in chickens, and 24.8% in the Doppelfish compared with the corresponding controls. Conclusion The SS yolk Ab2 was prepared successfully. It had a high titer, concentration and specificity. It is an Ab2ß as a vaccine can increase body weight of animals significantly by small-dose immunization only once.


Assuntos
Anticorpos Anti-Idiotípicos , Galinhas , Gema de Ovo , Somatostatina , Animais , Anticorpos Anti-Idiotípicos/análise , Anticorpos Anti-Idiotípicos/metabolismo , Gema de Ovo/química , Ensaio de Imunoadsorção Enzimática , Feminino , Peixes , Crescimento/fisiologia , Imunização , Camundongos
8.
J Photochem Photobiol B ; 194: 135-139, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30954872

RESUMO

Zika virus (ZIKV) has been declared a public health emergency of international concern. ZIKV has been associated with some neurological disorders, and their long-term effects are not completely understood. The majority of the methods for ZIKV diagnosis are based on the detection of IgM antibodies, which are the first signs of immunological response. However, the detection of IgG antibodies can be an important approach for ZIKV past infection diagnosis, especially for pregnant women, helping the comprehension/treatment of this disease. There has been a growing interest in applying nanoparticles for efficient ZIKV or antibodies detection. Quantum dots (QD) are unique fluorescent semiconductor nanoparticles, highly versatile for biological applications. In the present study, we explored the special QD optical properties to develop an immunofluorescence assay for anti-ZIKV IgG antibodies detection. Anti-IgG antibodies were successfully conjugated with QDs and applied in a fluorescence sensing nanoplatform. After optimization using IgG antibodies, the conjugates were employed to detect anti-ZIKV IgG antibodies in polystyrene microplates sensitized with ZIKV envelope E protein. The nanoplatform was able to detect anti-ZIKV IgG antibodies in a concentration at least 100-fold lower than the amount expected for protein E immune response. Moreover, conjugates were able to detect the antibodies for at least 4 months. Thus, our results showed that this QDs-based fluoroimmunoplatform can be considered practical, simple and promising to detect Zika past infections and/or monitoring immune response in vaccine trials.


Assuntos
Anticorpos Anti-Idiotípicos/análise , Anticorpos Anti-Idiotípicos/química , Fluorimunoensaio/métodos , Pontos Quânticos/química , Zika virus/imunologia , Anticorpos Anti-Idiotípicos/imunologia , Compostos de Cádmio/química , Telúrio/química , Zika virus/isolamento & purificação
9.
Anal Chim Acta ; 1024: 153-160, 2018 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-29776541

RESUMO

To achieve the dual-channel (analog and digital) encoding, microbeads assembled with quantum dots (QDs) and element coding nanoparticles (ECNPs) have been prepared. Dual-spectra, including fluorescence generated from quantum dots (QDs) and laser induced breakdown spectrum obtained from the plasma of ECNPs, including AgO, MgO and ZnO nanoparticles, has been adopted to provide more encoding amounts and more accurate dual recognition for encoded microbeads in multiplexed utilization. The experimental results demonstrate that the single microbead can be decoded in two optical channels. Multiplexed analysis and contrast adsorption experiment of anti-IgG verified the availability and specificity of dual-channel-coded microbeads in bioanalysis. In gradient detection of anti-IgG, we obtained the linear concentration response to target biomolecules from 3.125 × 10-10 M to 1 × 10-8 M, and the limit of detection was calculated to be 2.91 × 10-11 M.


Assuntos
Anticorpos Anti-Idiotípicos/análise , Nanopartículas Metálicas/química , Microesferas , Pontos Quânticos/química , Animais , Anticorpos Anti-Idiotípicos/química , Complexo Antígeno-Anticorpo/química , Fluorescência , Limite de Detecção , Óxido de Magnésio/química , Camundongos , Fenômenos Ópticos , Óxidos/química , Poliestirenos/química , Coelhos , Ratos , Compostos de Prata/química , Óxido de Zinco/química
10.
BMC Infect Dis ; 18(1): 156, 2018 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-29609533

RESUMO

BACKGROUND: Initial symptoms of dengue fever are non-specific, and thus definite diagnosis requires laboratory confirmation. Detection of IgM against dengue virus (DENV) has become widely used for dengue diagnosis. Understanding the persistence of anti-DENV IgM in subjects after acute infection is essential in order to interpret test results correctly. Although the longevity of anti-DENV IgM has been vehemently investigated in symptomatic children, anti-DENV IgM persistence in adults and in asymptomatically infected people have seldom been reported. METHODS: We prospectively investigated 44 adults with detectable anti-DENV IgM in a serosurvey conducted in the 2015 dengue epidemic in Tainan, Taiwan. Among subjects within the cohort, 17 were classified to be symptomatic and 27 were asymptomatic. The enzyme-linked immunosorbent assay (ELISA) from Standard Diagnostic (SD) and Focus Diagnostic were used to detect anti-DENV IgM for specimens collected initially, at 6 and 12 months. Regression analyses were used to estimate the duration of anti-DENV IgM fell below the detectable level. Rapid dengue tests from Standard Diagnostics had been widely adopted to detect anti-DENV IgM in Taiwan during the 2015 dengue outbreak. As such, collected specimens were also evaluated with the SD rapid dengue test in parallel. RESULTS: Anti-DENV IgM was detectable in 70.5 and 46.2% of the 44 subjects at 6 months and 12 months by the SD ELISA, respectively, while 13.6 and 7.7%, respectively, by the Focus ELISA. There was no significant difference in anti-DENV IgM detection for the follow-up specimens between subjects with symptomatic and asymptomatic infections. The regression analysis estimated that anti-DENV IgM persistence fell to the undetectable level at 338.3 days (95% CI 279.7-446.9) by SD ELISA, while at 175.7 days (95% CI 121.9-221.1) by Focus ELISA. The detectable frequency of anti-DENV IgM by rapid tests was 86.4%, 68.2 and 35.9% at initial, 6 and 12 months, respectively. CONCLUSION: Anti-DENV IgM was found to persist much longer than previously thought, suggesting a necessity of re-evaluation of the use of anti-DENV IgM for both the diagnosis of dengue and serological surveillance, especially when large outbreaks have occurred in the preceding year.


Assuntos
Anticorpos Antivirais/sangue , Vírus da Dengue/imunologia , Dengue/diagnóstico , Imunoglobulina M/sangue , Adulto , Idoso , Anticorpos Anti-Idiotípicos/análise , Estudos de Coortes , Comércio , Dengue/sangue , Dengue/imunologia , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Kit de Reagentes para Diagnóstico , Testes Sorológicos , Taiwan , Proteínas não Estruturais Virais/imunologia , Adulto Jovem
11.
Curr Opin Pulm Med ; 24(1): 83-93, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29059087

RESUMO

PURPOSE OF REVIEW: Despite currently available treatments, many asthma patients remain inadequately controlled, but identifying distinct patient populations (phenotypes/endotypes) may optimize their management. This review discusses some of the controversies and opportunities for improved disease control in severe asthma. RECENT FINDINGS: Currently approved anti-immunoglobulin E and anti-interleukin 5 biologics, which target specific pathways instead of using a 'one size fits all' strategy, are efficacious and well tolerated therapies for severe asthma. The appropriate use of these biologics, and of those in development (e.g., benralizumab and dupilumab), should be aided by further understanding of asthma phenotypes and endotypes, utilizing appropriate biomarkers.Oral corticosteroids are often added as maintenance therapy for patients with severe uncontrolled asthma, but their use is associated with significant adverse effects and should be considered a last option. The true cost of this therapy, including the cost of morbidities associated with its use, remains to be determined.Severe asthma in pediatrics poses a unique opportunity for possible prevention strategies and the potential for primary prevention. Although several avenues for primary prevention are being explored and are out of the scope of this review, we focus our discussion on the use of omalizumab, which has been recently explored in clinical trials. SUMMARY: Appropriate use of biologics in severe asthma should be supported by further understanding of biomarkers predicting response to targeted therapy. Because of their association with significant adverse effects, add-on oral corticosteroids should be considered a last treatment option for patients with uncontrolled severe asthma. Finally, severe asthma in pediatrics poses a unique opportunity for potential prevention strategies.


Assuntos
Antiasmáticos/uso terapêutico , Asma/tratamento farmacológico , Produtos Biológicos/uso terapêutico , Medicina de Precisão , Anticorpos Anti-Idiotípicos/análise , Asma/imunologia , Biomarcadores/análise , Humanos , Interleucina-5/análise , Fenótipo , Valor Preditivo dos Testes
12.
Cytokine ; 101: 70-77, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29174881

RESUMO

Patients treated with the TNF antagonist adalimumab develop anti-therapeutic antibodies (ATA), the prevalence of which varies depending on the assay used. Most assays are compromised due to the presence of adalimumab in the clinical samples. Our objective was to develop an antibody assay, applicable for clinical testing, which overcomes the limitation of therapeutic interference and to further determine the relationship between ATA development, adalimumab levels and disease activity in patients with rheumatoid arthritis (RA), psoriatic arthritis (PsA) or ankylosing spondylitis (AS). Use of an electrochemiluminescence platform permitted development of fit-for-purpose immunoassays. Serum samples from patients, taken prior to and at 12 and 24 weeks of treatment, were retrospectively analysed for levels of adalimumab and ATA. Overall, the antibody prevalence was 43.6% at 12 weeks and 41% at 24 weeks of treatment. Disruption of immune complexes by acid dissociation, a strategy often adopted for this purpose, only marginally increased the antibody prevalence to 48.7% and 46% at 12 and 24 weeks respectively. We found that antibody formation was associated with decreasing levels of circulating adalimumab, but no direct effect on disease activity was evident as assessed using DAS28 for RA patients and BASDAI for PsA and AS patients. However, a negative correlation of free adalimumab trough levels with disease activity scores was observed. Data showed that adalimumab levels can serve as an indicator of ATA development which can then be confirmed by ATA testing. Monitoring of both therapeutic and antibodies should be considered during adalimumab therapy to allow clinicians to personalise treatments for maximal therapeutic outcomes.


Assuntos
Adalimumab/efeitos adversos , Anti-Inflamatórios/efeitos adversos , Anticorpos Anti-Idiotípicos/análise , Anticorpos Anti-Idiotípicos/biossíntese , Anticorpos Monoclonais Humanizados/efeitos adversos , Adalimumab/administração & dosagem , Adalimumab/sangue , Adalimumab/uso terapêutico , Adulto , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/imunologia , Anti-Inflamatórios/uso terapêutico , Anticorpos Anti-Idiotípicos/imunologia , Anticorpos Monoclonais Humanizados/administração & dosagem , Anticorpos Monoclonais Humanizados/sangue , Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Neutralizantes/imunologia , Complexo Antígeno-Anticorpo , Artrite Psoriásica/tratamento farmacológico , Artrite Reumatoide/tratamento farmacológico , Técnicas Eletroquímicas , Feminino , Humanos , Imunoensaio/instrumentação , Imunoensaio/métodos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Espondilite Anquilosante/tratamento farmacológico , Fator de Necrose Tumoral alfa/imunologia
13.
Opt Express ; 25(22): 26950-26957, 2017 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-29092176

RESUMO

We present a dual-resonance fiber surface plasmon resonance (SPR) sensor for biological analysis. The sensing element was fabricated by sequentially sputtering layers of indium tin oxide (ITO) (100 nm thickness) and Au (35 nm thickness) on the surface of an optical fiber. The refractive index dispersion effect of ITO material led to resonances in the near infrared and visible wavelength regions. The refractive index of ITO is larger than the optical fiber in visible spectral area (400 to 733nm), such that the structure is a typical Kretschmann configuration surface plasmon resonance sensor. However, an Otto configuration is observed in the near infrared area (NIR) due to the ITO refractive index being smaller than the fiber core. We characterized the sensor performance by measuring bulk refractive index (RI) sensitivity in the two configurations, which were 1345 nm/RIU in the Kretschmann configuration and 1100 nm/RIU in the Otto configuration. In addition, this sensor was applied for real-time and label-free monitoring of the IgG/anti-IgG biomolecular interaction. As a robust and ultra-compact SPR sensor, which possesses wide detection range and is highly sensitive, this fiber SPR sensor can be applied for real-time biological analysis and monitoring.


Assuntos
Técnicas Biossensoriais , Ressonância de Plasmônio de Superfície , Anticorpos Anti-Idiotípicos/análise , Imunoglobulina G/análise , Fibras Ópticas , Refratometria , Compostos de Estanho
14.
Bioanalysis ; 9(23): 1849-1858, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29020795

RESUMO

BACKGROUND: Titer methods are commonly used to characterize the magnitude of an antidrug antibody response. Assay S/N is an appealing alternative, but the circumstances under which use of signal-to-noise (S/N) is appropriate have not been well defined. RESULTS: We validated both titer and S/N-based methods for several therapeutics. S/N correlated strongly with titer both in aggregate and when examined on a per subject basis. Analysis of impact of antibody magnitude on pharmacokinetics yielded the same result using either method. Each assay demonstrated excellent precision, good linearity, and adequate drug tolerance. CONCLUSION: Under these circumstances, assay S/N is a valid alternative to titer for assessment of the magnitude of an antidrug antibody response.


Assuntos
Anticorpos Anti-Idiotípicos/análise , Anticorpos Monoclonais/imunologia , Anticorpos Anti-Idiotípicos/imunologia , Anticorpos Monoclonais/sangue , Reações Antígeno-Anticorpo , Humanos , Imunoensaio , Medições Luminescentes , Razão Sinal-Ruído
15.
J Biomed Opt ; 22(9): 1-7, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28936825

RESUMO

A laser-induced breakdown spectroscopy and fluorescence spectroscopy-coupled optical system is reported to demodulate digitally encoded suspension array in fluoroimmunoassay. It takes advantage of the plasma emissions of assembled elemental materials to digitally decode the suspension array, providing a more stable and accurate recognition to target biomolecules. By separating the decoding procedure of suspension array and adsorption quantity calculation of biomolecules into two independent channels, the cross talk between decoding and label signals in traditional methods had been successfully avoided, which promoted the accuracy of both processes and realized more sensitive quantitative detection of target biomolecules. We carried a multiplexed detection of several types of anti-IgG to verify the quantitative analysis performance of the system. A limit of detection of 1.48×10-10 M was achieved, demonstrating the detection sensitivity of the optical demodulation system.


Assuntos
Fluorimunoensaio/métodos , Espectrometria de Fluorescência/métodos , Anticorpos Anti-Idiotípicos/análise , Lasers , Sensibilidade e Especificidade
16.
Toxicon ; 138: 37-42, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28811248

RESUMO

Hypersensitive diseases that involve IgE reactivity are important concern of public, especially those encompassing the potential pathogenesis from the administration of horse serum-based therapeutics such as antivenoms. A method for the definitive diagnosis of reactive IgE is important for identifying allergic patients to control severe collateral effects during planned and emergency application of immunotherapies when the allergy source cannot be avoided for treatment. To date, no tests have been developed to accompany the wide range of antivenoms produced from horse sera. The aim of this was to develop a cost-effective ELISA of high sensitivity and specificity to detect circulating patient IgE that binds horse IgG3, the most prevalent antibody class in passive antibody therapies. Horse IgG3 was purified in a single step on jacalin-Sepharose and absorbed to standard ELISA plates as the capture molecule for reactive human IgE. The direct performance evaluation with allergenic and non-allergenic patient, together with competitive peptides assays, showed high sensitivity and specificity to detect human IgE that recognized horse IgG3. The analytical sensitivity and ED50 were calculated to be 0.01 µg mL-1 and 0.052 µg mL-1, respectively. The intra- and inter-assay coefficient of variation ranged from 3.3 to 11.1% and 4.0-8.0%, respectively. The horse IgG3-based ELISA assay can detect reactive allergenic IgE at picomolar concentrations. The coefficient of variation suggests that it can be easily standardized between laboratories, provide rapid and can be applied to population surveillance. Patient management during treatment for envenomation would be greatly improved by a robust and reliable diagnostic test for preexisting allergies to mitigate life-threating consequences of hypersensitivity.


Assuntos
Anticorpos Anti-Idiotípicos/análise , Ensaio de Imunoadsorção Enzimática/métodos , Imunoglobulina G/análise , Animais , Antivenenos/imunologia , Cavalos , Humanos , Hipersensibilidade/diagnóstico , Imunoglobulina G/imunologia , Sensibilidade e Especificidade
17.
Biosens Bioelectron ; 91: 623-628, 2017 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-28107743

RESUMO

We present a novel four-layer structure consisting of bottom, second, third, and surface layers in the sensing region, for a D-shaped step-index fiber-optic evanescent wave (FOEW) sensor. To reduce the background noise, the surface of the longitudinal section in the D-shaped region is coated with a light-absorbing film. We check the morphologies of the second and surface layers, examine the refractive indices (RIs) of the third and surface layers, and analyze the composition of the surface layer. We also investigate the effects of the thicknesses and RIs of the third and surface layers and the LA film on the light transmission and sensitivity of the FOEW sensors. The results highlight the very good sensitivity of the proposed FOEW sensor with a four-layer structure, which reached -0.077 (µg/l)-1 in the detection of the target antibody; the sensitivity of the novel FOEW sensor was 7.60 and 1.52 times better than that of a conventional sensor with a core-cladding structure and an FOEW sensor with a three-layer structure doped with GeO2. The applications of this high-sensitivity FOEW sensor can be extended to biodefense, disease diagnosis, and biomedical and biochemical analysis.


Assuntos
Técnicas Biossensoriais/instrumentação , Tecnologia de Fibra Óptica/instrumentação , Fibras Ópticas , Polímeros/química , Animais , Anticorpos Anti-Idiotípicos/análise , Anticorpos Anti-Idiotípicos/imunologia , Bálsamos/química , Combinação de Medicamentos , Desenho de Equipamento , Germânio/química , Cabras , Guta-Percha/química , Imunoglobulina G/análise , Imunoglobulina G/imunologia , Camundongos , Óxido de Zinco/química
19.
Bioanalysis ; 8(23): 2457-2474, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27855509

RESUMO

The 2016 10th Workshop on Recent Issues in Bioanalysis (10th WRIB) took place in Orlando, Florida with participation of close to 700 professionals from pharmaceutical/biopharmaceutical companies, biotechnology companies, contract research organizations, and regulatory agencies worldwide. WRIB was once again a 5-day, weeklong event - A Full Immersion Week of Bioanalysis including Biomarkers and Immunogenicity. As usual, it is specifically designed to facilitate sharing, reviewing, discussing and agreeing on approaches to address the most current issues of interest including both small and large molecules involving LCMS, hybrid LBA/LCMS, and LBA approaches, with the focus on biomarkers and immunogenicity. This 2016 White Paper encompasses recommendations emerging from the extensive discussions held during the workshop, and is aimed to provide the bioanalytical community with key information and practical solutions on topics and issues addressed, in an effort to enable advances in scientific excellence, improved quality and better regulatory compliance. This White Paper is published in 3 parts due to length. This part (Part 2) discusses the recommendations for Hybrid LBA/LCMS and regulatory inputs from major global health authorities. Parts 1 (small molecule bioanalysis using LCMS) and Part 3 (large molecule bioanalysis using LBA, biomarkers and immunogenicity) have been published in the Bioanalysis journal, issues 22 and 23, respectively.


Assuntos
Biomarcadores/análise , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas , Anticorpos Anti-Idiotípicos/análise , Anticorpos Anti-Idiotípicos/imunologia , Conferências de Consenso como Assunto , Órgãos Governamentais , Humanos , Imunoensaio , Ligantes , Estudos de Validação como Assunto
20.
BMC Infect Dis ; 16: 324, 2016 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-27392037

RESUMO

BACKGROUND: Crimean-Congo Haemorrhagic Fever Virus (CCHFV) is a zoonotic virus transmitted by Ixodid ticks and causes Crimean-Congo hemorrhagic fever (CCHF) disease in humans with up to 50 % mortality rate. METHODS: Freshly slaughtered livestock at the Kumasi abattoir in the Ashanti Region of Ghana were examined for the presence of ticks once a month over a 6-month period from May to November 2011. The ticks were grouped into pools by species, sex, and animal source. CCHFV was detected in the ticks using reverse transcription PCR. Blood samples were collected from enrolled abattoir workers at initiation, and from those who reported fever in a preceding 30-day period during monthly visits 2-5 months after initiation. Six months after initiation, all participants who provided baseline samples were invited to provide blood samples. Serology was performed using enzyme linked immunosorbent assay (ELISA). Demographic and epidemiological data was also obtained from enrolled participants using a structured questionnaire. RESULTS: Of 428 freshly slaughtered animals comprising 130 sheep, 149 cattle, and 149 goats examined, 144 ticks belonging to the genera Ambylomma, Hyalomma and Boophilus were identified from 57 (13.3 %): 52 (34.9 %), 4 (3.1 %) and 1 (0.7 %) cattle, sheep and goat respectively. Of 97 tick pools tested, 5 pools comprising 1 pool of Hyalomma excavatum and 4 pools of Ambylomma variegatum, collected from cattle, were positive for CCHFV. Of 188 human serum samples collected from 108 abattoir workers, 7 (3.7 %) samples from 6 persons were anti-CCHF IgG positive with one of them also being CCHF IgM positive. The seroprevalence of CCHFV identified in this study was 5.7 %. CONCLUSIONS: This study detected human exposure to CCHF virus in slaughterhouse workers and also identified the CCHF virus in proven vectors (ticks) of Crimean Congo hemorrhagic fever in Ghana. The CCHFV was detected only in ticks collected from cattle, one of the livestock known to play a role in the amplification of the CCHF virus.


Assuntos
Matadouros/estatística & dados numéricos , Doenças dos Trabalhadores Agrícolas/virologia , Vírus da Febre Hemorrágica da Crimeia-Congo/isolamento & purificação , Febre Hemorrágica da Crimeia/diagnóstico , Carrapatos/virologia , Adulto , Animais , Anticorpos Anti-Idiotípicos/análise , Bovinos , Ensaio de Imunoadsorção Enzimática , Feminino , Gana , Cabras , Vírus da Febre Hemorrágica da Crimeia-Congo/genética , Febre Hemorrágica da Crimeia/virologia , Humanos , Gado/parasitologia , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Estudos Soroepidemiológicos , Ovinos
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