المؤلفون: Rosabel Corrales, Rosabel Falcón, Susana Vázquez, Onelkis Feliciano, Reinaldo Mederos, Amílcar Duquesne, Oderay Gutierrez, Rafael Llanes

المصدر: Exploration of Digestive Diseases, Vol 3, Iss 3, Pp 190-202 (2024)

مصطلحات موضوعية: diagnostic accuracy, helicobacter pylori, antibody detection, elisa, Diseases of the digestive system. Gastroenterology, RC799-869

الوصف: Aim: This study aimed to develop and evaluate an in-house enzyme-linked immunosorbent assay (ELISA) based on autochthonous antigens to detect immunoglobulin G (IgG) antibodies against Helicobacter pylori (H. pylori) in adult sera. Methods: Whole-cell antigens from three genetically characterized clinical isolates of H. pylori were mixed and used as coating antigens. This assay was validated with a panel of human sera samples of H. pylori seropositive and seronegative patients. Likewise, sera samples from patients with uninvestigated dyspepsia, who were also evaluated by invasive and noninvasive tests (i.e., histopathology, rapid urease test, and stool antigen test), blood donors and patients with confirmed viral and parasitic diseases were also collected. The IgG response against H. pylori was detected by the in-house assay using the commercial ELISA IBL (Germany), as a reference test. Statistical analysis was performed with GraphPad Prism version 5.01. Results: The in-house ELISA showed high repeatability and reproducibility. Sensitivity was 91.1%; 95% confidence interval (CI): 87.2–94.0, specificity was 94.8% (95% CI: 85.0–94.8), and accuracy was 91.6% (95% CI: 88.5–94.6). The in-house ELISA showed an excellent area under the curve (0.96; 95% CI: 0.93–0.98) and a better IgG detection by the inverse cumulative distribution. The frequency of seropositivity in patients with dyspepsia (76.0%) was significantly higher (P < 0.05) than in healthy individuals (57.7%) and patients with other infectious diseases resembling H. pylori infection symptoms (54.4%). The H. pylori seroprevalence was estimated to be 62.7%. A good correlation was found between IgG seropositivity and H. pylori infection diagnosed by histopathology, rapid urease test, and stool antigen test in Cuban adults with dyspepsia. Conclusions: The in-house ELISA demonstrated good diagnostic accuracy and potential usefulness for estimating H. pylori exposure in the adult population, henceforward, this method could be used as an alternative for H. pylori diagnosis in the Cuban setting.

وصف الملف: electronic resource

العلاقة: https://www.explorationpub.com/Journals/edd/Article/100547Test; https://doaj.org/toc/2833-6321Test

الوصول الحر: https://doaj.org/article/0b763d11cacd4a65a3c54e1e912e4333Test

المؤلفون: Lind, Alexander, Freyhult, Eva, 1979, de Jesus Cortez, Felipe, Ramelius, Anita, Bennet, Rasmus, Robinson, Peter V., Seftel, David, Gebhart, David, Tandel, Devangkumar, Maziarz, Marlena, Elding Larsson, Helena, Lundgren, Markus, Carlsson, Annelie, Nilsson, Anna-Lena, Fex, Malin, Törn, Carina, Agardh, Daniel, Tsai, Cheng-ting, Lernmark, Åke

المصدر: EBioMedicine. 104

مصطلحات موضوعية: Type 1 diabetes, Insulin autoantibodies, GAD65 autoantibodies, IA-2 autoantibodies, ZnT8 autoantibodies, Radiobinding assay, Antibody detection by agglutination PCR, Diagnostic sensitivity, Diagnostic specificity

الوصف: BackgroundTwo or more autoantibodies against either insulin (IAA), glutamic acid decarboxylase (GADA), islet antigen-2 (IA-2A) or zinc transporter 8 (ZnT8A) denote stage 1 (normoglycemia) or stage 2 (dysglycemia) type 1 diabetes prior to stage 3 type 1 diabetes. Automated multiplex Antibody Detection by Agglutination-PCR (ADAP) assays in two laboratories were compared to single plex radiobinding assays (RBA) to define threshold levels for diagnostic specificity and sensitivity.MethodsIAA, GADA, IA-2A and ZnT8A were analysed in 1504 (54% females) population based controls (PBC), 456 (55% females) doctor's office controls (DOC) and 535 (41% females) blood donor controls (BDC) as well as in 2300 (48% females) patients newly diagnosed (1–10 years of age) with stage 3 type 1 diabetes. The thresholds for autoantibody positivity were computed in 100 10-fold cross-validations to separate patients from controls either by maximizing the χ2-statistics (chisq) or using the 98th percentile of specificity (Spec98). Mean and 95% CI for threshold, sensitivity and specificity are presented.FindingsThe ADAP ROC curves of the four autoantibodies showed comparable AUC in the two ADAP laboratories and were higher than RBA. Detection of two or more autoantibodies using chisq showed 0.97 (0.95, 0.99) sensitivity and 0.94 (0.91, 0.97) specificity in ADAP compared to 0.90 (0.88, 0.95) sensitivity and 0.97 (0.94, 0.98) specificity in RBA. Using Spec98, ADAP showed 0.92 (0.89, 0.95) sensitivity and 0.99 (0.98, 1.00) specificity compared to 0.89 (0.77, 0.86) sensitivity and 1.00 (0.99, 1.00) specificity in the RBA. The diagnostic sensitivity and specificity were higher in PBC compared to DOC and BDC.InterpretationADAP was comparable in two laboratories, both comparable to or better than RBA, to define threshold levels for two or more autoantibodies to stage type 1 diabetes.

وصف الملف: electronic

الوصول الحر: https://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-532277Test
https://doi.org/10.1016/j.ebiom.2024.105144Test
https://uu.diva-portal.org/smash/get/diva2:1873397/FULLTEXT01.pdfTest

المؤلفون: Wang, Mengqi, 1997

المساهمون: Landegren, Ulf, Professor, Ståhlberg, Anders, Professor

المصدر: Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Medicine.

مصطلحات موضوعية: Homogenous serological assay, PCR-based antibody detection, Proximity extension assay, SARS-CoV-2 antibody, Extracellular vesicles, Proximity barcoding assay, in situ superRCA, mutant transcript

الوصف: Advanced molecular diagnostics uses in vitro biological assays to detect nucleic acids or proteins even in low concentrations across samples, allowing for the identification of biomarkers, monitoring the course of the disease over time, and selection of appropriate therapy. In this thesis, I focus on development and early applications of several molecular tools of expected value in research, and eventually also clinically. In papers I and II, proximity extension assay (PEA) was for the first time modified to measure specific antibody responses, rather than protein levels as in the standard PEA. We call the method AbPEA and the technique was used to sensitively measure antibody responses to the spike protein or the nucleocapsid of SARS-CoV-2. We demonstrated that AbPEA has high specificity, sensitivity, and broad dynamic range, along with multiplexing potential, offering performance similar to that of other methods for antibody measurements. We demonstrated utilization of blood and saliva samples in paper I and paper II, respectively, which further establish that our approach has great potential for large-scale screening and biobanking. In paper III, we aimed to investigate how the protein composition of extracellular vesicles (EVs) differed among blood samples collected from healthy individual or ones with either mild or severe COVID-19. Proximity barcoding assay was applied to obtain a comprehensive overview of the protein composition of large numbers of individual EVs, demonstrating interesting differences. In paper IV, we enhanced padlock-RCA-based RNA genotyping in situ by using another newly developed technology for highly selective detection of DNA or RNA sequence variants, referred to as super RCA (sRCA). Our analysis showed that this approach can improve the selectivity for sequence variants during in situ detection of mutant or wild-type transcripts, and the signals representing superRCA reaction products are prominent and easily distinguished from any background.

وصف الملف: electronic

الوصول الحر: https://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-522118Test
https://uu.diva-portal.org/smash/get/diva2:1833453/FULLTEXT01.pdfTest
https://uu.diva-portal.org/smash/get/diva2:1833453/PREVIEW01.jpgTest

المؤلفون: Tianxiang Jiang, Xuanjie Ye, Zuyuan Tian, Mohamed Shaheen, Ahmed A. Khorshed, Yiwei Feng, Bingxuan Li, Yusheng Zhang, Xihua Wang, Jie Chen

المصدر: Biosensors and Bioelectronics: X, Vol 18, Iss , Pp 100479- (2024)

مصطلحات موضوعية: Electrochemical impedance spectroscopy (EIS), Impedimetric biosensors, Lab-on-chip, Point-of-care, Interdigitated electrode (IDE), Antibody detection, Biotechnology, TP248.13-248.65

الوصف: In this study, we examined the relationship between the sensitivity of interdigitated electrode (IDE) impedimetric biosensors and the gap between the IDEs. Our aim is to find an optimal design to maximize sensitivity. A three-dimensional COMSOL model was constructed for determining the effects of electrode gap, width, and height on impedance sensitivity, revealing a singular linear correlation with the inner gap. Considering both the simulation results and fabrication processes, we have developed three IDE prototype chips with electrode gaps of 3 μm, 4 μm, and 5 μm, respectively. For empirical validation, human anti-SARS-CoV-2 monoclonal antibody (mAb) was utilized, with immobilization of the SARS-CoV-2 spike protein on the chip's surface for mAb capture. This interaction, further amplified by Protein G conjugation, induced shifts in the impedance spectrum. The sensitivity of each prototype chip was evaluated across mAb concentrations ranging from 50 ng/mL to 500 ng/mL. The 3 μm configuration emerged as the most sensitive, demonstrating the ability to detect mAb concentrations as low as 50 ng/mL, a threshold unattainable by the other designs. This outcome underscores the critical influence of reduced inter-electrode gap on enhancing biosensor detection limits. The findings from this investigation offer a foundational approach for advancing biosensor sensitivity via electrode geometric optimization, with broad potential applications extending beyond COVID-19 diagnostics to a wide spectrum of clinical and research contexts.

وصف الملف: electronic resource

العلاقة: http://www.sciencedirect.com/science/article/pii/S2590137024000438Test; https://doaj.org/toc/2590-1370Test

الوصول الحر: https://doaj.org/article/fedf37538fd0493186f47b0ad337474dTest

المؤلفون: María Ahumada, Agustina Godino, Lorena Guasconi, Carla Deheza, Marilla Amaranto, Cesar Iván Pruzzo, Gabriel Vitulli-Moya, Laura Chiapello, María Elena Carrizo, José Luis Barra, Laura Cervi

المصدر: International Journal of Veterinary Science and Medicine, Vol 11, Iss 1, Pp 126-137 (2023)

مصطلحات موضوعية: Sheep, Fasciola hepatica, early diagnosis, Kunitz-type protein, antibody detection, Veterinary medicine, SF600-1100

الوصف: ABSTRACTFasciolosis is a parasitic disease considered as emerging and neglected by the WHO. Sheep are highly susceptible to this disease, and affected flocks experience decreased productivity due to increased mortality, and the reduced quality of their products, such as wool and meat. To effectively control this disease, reliable and early diagnosis is essential for making decisions regarding antiparasitic application and/or the removal of affected animals. Currently, the diagnosis of F. hepatica in sheep relies on the detection of parasite eggs in faeces, a method that becomes reliable from week 10 post-infection. Consequently, there is a need for earlier diagnostic tools based on immune response. However, obtaining antigens for antibody detection has proven to be difficult and expensive. The aim of this study was to evaluate members of the Kunitz protein family of F. hepatica expressed in the form of a fusion protein in the serological diagnosis of F. hepatica in sheep. The performance of three recombinant F. hepatica Kunitz-type inhibitors (FhKT1.1, FhKT1.3, and FhKT4) was compared with a synthetic Kunitz-type peptide (sFhKT) in sera from sheep experimentally infected with F. hepatica, using an ELISA. Of these, FhKT1.1 showed the most promising diagnostic indicators, exhibiting high precision and low cross-reactivity, and thus potential for standardized production. The results of our study demonstrated that the application of FhKT1.1 is a valuable tool for early-stage diagnosis of F. hepatica in sheep. Such an early diagnosis can aid in implementing timely interventions and effectively managing the disease in sheep populations.

وصف الملف: electronic resource

العلاقة: https://doaj.org/toc/2314-4599Test

الوصول الحر: https://doaj.org/article/5e24f12ce1794a6c8b0eebdf8e9cb6b5Test

المؤلفون: Loc Tan Huynh, Eun-Ju Sohn, Youngmin Park, Juhun Kim, Tomohiko Shimoda, Takahiro Hiono, Norikazu Isoda, Sung-Hee Hong, Ha-Na Lee, Yoshihiro Sakoda

المصدر: Frontiers in Microbiology, Vol 15 (2024)

مصطلحات موضوعية: classical swine fever, immunochromatographic test strip, E2, Erns, antibody detection, Microbiology, QR1-502

الوصف: BackgroundIt is essential to consider a practical antibody test to successfully implement marker vaccines and validate vaccination efficacy against classical swine fever virus (CSFV). The test should include a serological antibody assay, combined with a tool for differentiating infected from vaccinated animals (DIVA). The immunochromatographic test strip (ICS) has been exclusively designed for detecting CSFV E2 antibodies while lacking in detecting Erns antibodies, which can be employed and satisfy DIVA strategy. This study developed a novel ICS for detecting CSFV E2/Erns dual-antibody. The effectiveness of ICS in evaluating the DIVA capability of two novel chimeric pestivirus vaccine candidates was assessed.MethodsRecombinant E2 or Erns protein was transiently expressed in the plant benthamiana using Agrobacterium tumefaciens. ICS was subsequently assembled, and goat anti-rabbit IgG and recombinant CSFV E2 or Erns protein were plated onto the nitrocellulose membrane as control and test lines, respectively. The sensitivity and specificity of ICS were evaluated using sera with different neutralizing antibody titers or positive for antibodies against CSFV and other pestiviruses. The coincidence rates for detecting E2 and Erns antibodies between ICS and commercial enzyme-linked immunosorbent assay (ELISA) kits were also computed. ICS performance for DIVA capability was evaluated using sera from pigs vaccinated with conventional vaccine or chimeric vaccine candidates.ResultsE2 and Erns proteins were successfully expressed in N. benthamiana-produced recombinant proteins. ICS demonstrated high sensitivity in identifying CSFV E2 and Erns antibodies, even at the low neutralizing antibody titers. No cross-reactivity with antibodies from other pestiviruses was confirmed using ICS. There were high agreement rates of 93.0 and 96.5% between ICS and two commercial ELISA kits for E2 antibody testing. ICS also achieved strong coincidence rates of 92.9 and 89.3% with two ELISA kits for Erns antibody detection. ICS confirmed the absence of CSFV Erns-specific antibodies in sera from pigs vaccinated with chimeric vaccine candidates.ConclusionE2 and Erns proteins derived from the plant showed great potential and can be used to engineer a CSFV E2/Erns dual-antibody ICS. The ICS was also highly sensitive and specific for detecting CSFV E2 and Erns antibodies. Significantly, ICS can fulfill the DIVA concept by incorporating chimeric vaccine candidates.

وصف الملف: electronic resource

العلاقة: https://www.frontiersin.org/articles/10.3389/fmicb.2024.1383976/fullTest; https://doaj.org/toc/1664-302XTest

الوصول الحر: https://doaj.org/article/e10cd822c06c4c87a295febd86670bd1Test

المؤلفون: Xing GUO, Man LUO, Jianru HOU, Yuchao LI, Shuhua WANG, Xiaoliang CHENG, Aoqun JIAN, Zhongyun YUAN, Shengbo SANG

المصدر: Taiyuan Ligong Daxue xuebao, Vol 54, Iss 5, Pp 891-897 (2023)

مصطلحات موضوعية: magnetoelastic device, classical swine fever virus e2 antibody detection, calibrating-free, portable, Chemical engineering, TP155-156, Materials of engineering and construction. Mechanics of materials, TA401-492, Technology

الوصف: Purposes Error calibration between equipment manufacturing has become a practical challenge for various inspection methods. Methods In this paper, a portable magnetoelastic (ME) biodetection device is proposed for calibration-free detection of classical swine fever virus E2 antibody (anti-CSFV E2), on the basis of magnetostrictive effect, by monitoring the resonance frequency shift caused by anti-CSFV E2 to react to the concentration of analytes. The device consists of two parts, namely the magnetoelastic test strip and the intelligent magnetoelastic resonance frequency detector. The test strip is very small, and the external dimension is about 1/20 of the size of the ELISA kit. By using the ELISA kit as a control, the accuracy of the portable ME device is verified by detecting the same concentration of pig serum samples. Findings The results show that the detection results of the calibration-free portable ME device and the ELISA kit have good consistency, and the accuracy rate is 98%. The experimental results show that the sensitivity is 7.20 Hz/(μg/mL) and the linear range is 0.1~100 μg/mL, and the device can quickly and accurately detect anti-CSFV E2 without calibration, with good specificity and stability. Conclusions The calibration-free portable ME unit provides an effective method for the diagnosis of swine fever and the monitoring of the effectiveness of anti-swine fever vaccination.

وصف الملف: electronic resource

العلاقة: https://tyutjournal.tyut.edu.cn/englishpaper/show-2122.htmlTest; https://doaj.org/toc/1007-9432Test

الوصول الحر: https://doaj.org/article/5dd13959f94f41a0be6e095a773226a5Test

المؤلفون: Daniel Felipe Barrantes Murillo, Lindsay Starkey, Theresa Wood, Rachel Smith, Byron Blagburn, Joy Bowles, Hill Allen, Caroline Lewis, Yue Shu, Chengming Wang

المصدر: Parasites & Vectors, Vol 16, Iss 1, Pp 1-9 (2023)

مصطلحات موضوعية: Dirofilaria immitis, Companion cats, USA, Antigen testing, Antibody detection, Acid treatment, Infectious and parasitic diseases, RC109-216

الوصف: Abstract Background Feline heartworm disease (HWD) is a complex and often misdiagnosed disease in cats, caused by the filarial nematode Dirofilaria immitis. Despite its significant impact, studies reporting the prevalence of D. immitis in apparently healthy pet cats in the USA are lacking. Methods To investigate feline heartworm seroprevalence in apparently healthy pet cats in the USA, serum samples (n = 2165) collected from cats across 47 states and Washington District of Columbia were analyzed for D. immitis antibody (Heska Corp.) and antigen (DiroCHEK®; Zoetis Inc.) with and without acid treatment of the samples. Results Antibodies to D. immitis antibodies were identified in 3.5% (76/2165) of cats from 26 states, with a significantly higher prevalence in cats from the westernmost US states (West region; 5.4%, 23/429) compared to those from the South (3.8%, 32/847), Midwest (2.7%, 9/338) and Northeast regions (2.2%, 12/551) (P

وصف الملف: electronic resource

العلاقة: https://doaj.org/toc/1756-3305Test

الوصول الحر: https://doaj.org/article/6cc012d85a16408a828e82c0078dd5ffTest

المؤلفون: Li Y, He X, Deng L, Chen H, Chen X, Mao X, Xiang Y

المصدر: Infection and Drug Resistance, Vol Volume 16, Pp 5613-5625 (2023)

مصطلحات موضوعية: melioidosis abscess, serodiagnosis, burkholderia pseudomallei, antibody detection, hcp-1, Infectious and parasitic diseases, RC109-216

الوصف: Yuanli Li,1,* Xiaoyi He,2,* Ling Deng,2 Hai Chen,1 Xi Chen,1 Xuhu Mao,2 Yang Xiang2 1Department of Clinical Laboratory, Sanya People’s Hospital, Sanya, Hainan, People’s Republic of China; 2Department of Clinical Microbiology and Immunology, College of Pharmacy and Laboratory Medicine Science, Third Military Medical University (Army Medical University), Chongqing, People’s Republic of China*These authors contributed equally to this workCorrespondence: Yang Xiang, Email xiangyang@tmmu.edu.cnAbstract: Burkholderia pseudomallei, the causative agent of melioidosis can be responsible for a wide spectrum of clinical manifestations and heterogeneous prognoses, with a high mortality in the acute onset. We report a case of a deep abdominal abscess with sepsis secondary to melioidosis in a young farmer from a non-high-risk population. Emergency medical treatment was administered according to the detection of serum antibodies against Hcp1, the results of which provided etiological evidence of B. pseudomallei infection for the timely and properly antimicrobial therapy in the absence of direct evidence of melioidosis. To our knowledge, this is the first reported case of serodiagnosis of acute exacerbation of melioidosis in China.Keywords: melioidosis abscess, serodiagnosis, Burkholderia pseudomallei, antibody detection, Hcp-1

وصف الملف: electronic resource

العلاقة: https://www.dovepress.com/serodiagnosis-of-abdominal-abscess-caused-by-burkholderia-pseudomallei-peer-reviewed-fulltext-article-IDRTest; https://doaj.org/toc/1178-6973Test

الوصول الحر: https://doaj.org/article/bdbd0d6d595e495db1fe0a5dd8801910Test

المؤلفون: Yuanyuan Tian, Chao Liang, Jingming Zhou, Fanglin Sun, Yankai Liu, Yumei Chen, Xifang Zhu, Hongliang Liu, Peiyang Ding, Enping Liu, Ying Zhang, Sixuan Wu, Aiping Wang

المصدر: Frontiers in Microbiology, Vol 14 (2024)

مصطلحات موضوعية: African swine fever virus, p34 protein, monoclonal antibody, B-cell epitope, antibody detection, ELISA, Microbiology, QR1-502

الوصف: African swine fever (ASF) is a viral disease caused by the African swine fever virus that can be highly transmitted and lethal in domestic pigs. In the absence of a vaccine, effective diagnosis is critical for minimizing the virus’s spread. In recent years, with the decline of African swine fever virus (ASFV) virulence, antibody detection has become an important means of detection. ASFV nucleocapsid protein p34 is a mature hydrolytic product of pp220, which is highly conserved and has a high content in the structural protein of the virus. Prokaryotic cells were chosen to generate highly active and high-yield p34 protein, which was then used as an antigen for producing mouse monoclonal antibodies. The B-cell epitope 202QKELDKLQT210, which was highly conserved and found on the surface of the p34 protein, was first identified by an anti-p34 monoclonal antibody utilizing the peptide scanning technique and visualized in helix. This supported the viability of p34 protein detection even further. In addition, we established an indirect ELISA assay based on p34 to detect ASFV antibodies. The coincidence rate of this method with commercially available kits was shown to be 97.83%. Sensitivity analysis revealed that it could be detected in serum dilution as low as 1:6400, and there was no cross-reaction with other prevalent porcine epidemic diseases classical swine fever virus (CSFV), foot-and-mouth disease virus (FMDV), porcine reproductive and respiratory syndrome virus (PRRSV), and porcine circovirus 2 (PCV2). In summary, the established ELISA method and anti-P34 monoclonal antibody have demonstrated that the p34 protein has a promising application prospect for the detection of African swine fever antibodies.

وصف الملف: electronic resource

العلاقة: https://www.frontiersin.org/articles/10.3389/fmicb.2023.1308753/fullTest; https://doaj.org/toc/1664-302XTest

الوصول الحر: https://doaj.org/article/c8f27b20dfa6433fb7ed3b7d3cf29a13Test