RESUMO
Human cytomegalovirus (HCMV) infection remains a major complication for solid organ transplant recipients (SOTRs). The aim of this study was to evaluate the role of HCMV-specific T cell immunity measured at the time of the HCMV-DNA peak in predicting the spontaneous clearance of infection. The performance of cytokine flow cytometry using infected dendritic cells (CFC-iDC), infected cell lysate (CFC-iCL) and pp65 peptide pool (CFC-pp65 pool) as stimuli, as well as ELISPOT assays using infected cell lysate (ELISPOT-iCL) and the pp65 peptide pool (ELISPOT-pp65 pool), was analysed. Among the 40 SOTRs enrolled, 16 patients (40%) required antiviral treatment for an HCMV infection (Non-Controllers), while the others spontaneously cleared the infection (Controllers). At the HCMV-DNA peak, the number of HCMV-specific CD4+ T cells detected by the CFC-iDC, CFC-iCL and CFC-pp65 pool assays in Controllers was higher than that detected in Non-Controllers, while no difference was observed in terms of HCMV-specific CD8+ T cell response. The same trend was observed when the HCMV-specific T cell response was measured by ELISPOT-iCL and ELISPOT-pp65 pool. We observed that the CD4+ CFC-pp65 pool assay was the best predictor of self-resolving HCMV infection at the time of the HCVM-DNA peak. The CFC-pp65 pool assay is able to discriminate between CD4+ and CD8+ T cell responses and could be used in daily clinical practice.
Assuntos
Infecções por Citomegalovirus , Citomegalovirus , Transplantados , Humanos , Infecções por Citomegalovirus/imunologia , Infecções por Citomegalovirus/virologia , Citomegalovirus/imunologia , Feminino , Masculino , Pessoa de Meia-Idade , Adulto , Transplante de Órgãos/efeitos adversos , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD4-Positivos/imunologia , Idoso , DNA Viral , Células Dendríticas/imunologia , ELISPOT , Testes Imunológicos/métodos , Citocinas/metabolismoRESUMO
Helicobacter pylori (H. pylori) strain is the most genetically diverse pathogenic bacterium and now alarming serious human health concern ranging from chronic gastritis to gastric cancer and human death all over the world. Currently, the majority of commercially available diagnostic assays for H. pylori is a challenging task due to the heterogeneity of virulence factors in various geographical regions. In this concern, designing of universal multi-epitope immunogenic biomarker targeted for all H. pylori strains would be crucial to successfully immunodiagnosis assay and vaccine development for H. pylori infection. Hence, the present study aimed to explore the potential immunogenic epitopes of PSA D15 and Cag11 proteins of H. pylori, using immunoinformatics web tools in order to design novel immune-reactive multi-epitope antigens for enhanced immunodiagnosis in humans. Through an in silico immunoinformatics approach, high-ranked B-cell, MHC-I, and MHC-II epitopes of PSA D15 and Cag11 proteins were predicted, screened, and selected. Subsequently, a novel multi-epitope PSA D15 and Cag11 antigens were designed by fused the high-ranked B-cell, MHC-I, and MHC-II epitopes and 50S ribosomal protein L7/L12 adjuvant using linkers. The antigenicity, solubility, physicochemical properties, secondary and tertiary structures, 3D model refinement, and validations were carried. Furthermore, the designed multi-epitope antigens were subjected to codon adaptation and in silico cloning, immune response simulation, and molecular docking with receptor molecules. A novel, stable multi-epitope PSA D15 and Cag11 H. pylori antigens were developed and immune simulation of the designed antigens showed desirable levels of immunological response. Molecular docking of designed antigens with immune receptors (B-cell, MHC-I, MHC-II, and TLR-2/4) revealed robust interactions and stable binding affinity to the receptors. The codon optimized and in silico cloned showed that the designed antigens were successfully expressed (CAI value of 0.95 for PSA D15 and 1.0 for Cag11) after inserted into pET-32ba (+) plasmid of the E. coli K12 strain. In conclusion, this study revealed that the designed multi-epitope antigens have a huge immunological potential candidate biomarker and useful in developing immunodiagnostic assays and vaccines for H. pylori infection.
Assuntos
Antígenos de Bactérias , Biologia Computacional , Helicobacter pylori , Helicobacter pylori/imunologia , Helicobacter pylori/genética , Antígenos de Bactérias/imunologia , Antígenos de Bactérias/genética , Antígenos de Bactérias/química , Humanos , Infecções por Helicobacter/diagnóstico , Infecções por Helicobacter/imunologia , Infecções por Helicobacter/microbiologia , Proteínas de Bactérias/imunologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/química , Epitopos/imunologia , Testes Imunológicos/métodos , Simulação de Acoplamento Molecular , Vacinas Bacterianas/imunologia , Vacinas Bacterianas/genética , ImunoinformáticaRESUMO
Recombinant multiepitope proteins (RMPs) are a promising alternative for application in diagnostic tests and, given their wide application in the most diverse diseases, this review article aims to survey the use of these antigens for diagnosis, as well as discuss the main points surrounding these antigens. RMPs usually consisting of linear, immunodominant, and phylogenetically conserved epitopes, has been applied in the experimental diagnosis of various human and animal diseases, such as leishmaniasis, brucellosis, cysticercosis, Chagas disease, hepatitis, leptospirosis, leprosy, filariasis, schistosomiasis, dengue, and COVID-19. The synthetic genes for these epitopes are joined to code a single RMP, either with spacers or fused, with different biochemical properties. The epitopes' high density within the RMPs contributes to a high degree of sensitivity and specificity. The RMPs can also sidestep the need for multiple peptide synthesis or multiple recombinant proteins, reducing costs and enhancing the standardization conditions for immunoassays. Methods such as bioinformatics and circular dichroism have been widely applied in the development of new RMPs, helping to guide their construction and better understand their structure. Several RMPs have been expressed, mainly using the Escherichia coli expression system, highlighting the importance of these cells in the biotechnological field. In fact, technological advances in this area, offering a wide range of different strains to be used, make these cells the most widely used expression platform. RMPs have been experimentally used to diagnose a broad range of illnesses in the laboratory, suggesting they could also be useful for accurate diagnoses commercially. On this point, the RMP method offers a tempting substitute for the production of promising antigens used to assemble commercial diagnostic kits.
Assuntos
Epitopos , Escherichia coli , Proteínas Recombinantes , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/imunologia , Humanos , Epitopos/imunologia , Epitopos/genética , Testes Imunológicos/métodos , Animais , COVID-19/diagnósticoRESUMO
Importance: Given a gradient relationship between fecal hemoglobin (f-Hb) concentration and colorectal neoplasia demonstrated previously, using f-Hb-guided interscreening interval has increasingly gained attention in population-based fecal immunological test (FIT), but it is very rare to address how to implement such a precision strategy and whether it can economize the use of FIT and colonoscopy. Objective: To demonstrate the applicability of personalized colorectal cancer (CRC) screening with f-Hb-guided screening intervals to reduce the number of FITs and colonoscopy with as equivalent efficacy as universal biennial screening. Design, Setting, and Participants: A retrospective cohort study for developing f-Hb-guided precision interscreening interval was conducted using data on a Taiwanese biennial nationwide FIT screening program that enrolled more than 3 million participants aged 50 to 74 years between 2004 and 2014. The cohort was followed up over time until 2019 to ascertain colorectal neoplasia and causes of death. A comparative study was further designed to compare the use of FIT and colonoscopy between the personalized f-Hb-guided group and the universal biennial screening group given the equivalent efficacy of reducing CRC-related outcomes. Main Outcomes and Measurements: A spectrum of f-Hb-guided intervals was determined by using the Poisson regression model given the equivalent efficacy of a universal biennial screening. The use of FIT and colonoscopy for the pragmatic f-Hb-guided interval group was measured compared with the universal biennial screening group. Data analysis was performed from September 2022 to October 2023. Results: Using data from the 3â¯500â¯250 participants (mean [SD] age, 57.8 [6.0] years) enrolled in the Taiwanese biennial nationwide FIT screening program, an incremental increase in baseline f-Hb associated with colorectal neoplasia and CRC mortality consistently was observed. Participants with different f-Hb levels were classified into distinct risk categories. Various screening intervals by different f-Hb levels were recommended. Using the proposed f-Hb-guided screening intervals, it was found that the personalized method was imputed to reduce the number of FIT tests and colonoscopies by 49% and 28%, respectively, compared with the universal biennial screening. Conclusion and Relevance: The gradient relationship between f-Hb and colorectal neoplasia and CRC mortality was used to develop personalized FIT screening with f-Hb-guided screening intervals. Such a precision interscreening interval led to the reduced use of FIT test and colonoscopy without compromising the effectiveness of universal biennial screening.
Assuntos
Neoplasias Colorretais , Detecção Precoce de Câncer , Fezes , Hemoglobinas , Humanos , Neoplasias Colorretais/diagnóstico , Pessoa de Meia-Idade , Feminino , Masculino , Hemoglobinas/análise , Idoso , Detecção Precoce de Câncer/métodos , Estudos Retrospectivos , Fezes/química , Colonoscopia , Sangue Oculto , Testes Imunológicos/métodos , Taiwan/epidemiologia , Medicina de PrecisãoRESUMO
Chagas disease, caused by the protozoa Trypanosoma cruzi, continues to be a serious public health problem in Latin America, worsened by the limitations in its detection. Given the importance of developing new diagnostic methods for this disease, the present review aimed to verify the number of publications dedicated to research on peptides that demonstrate their usefulness in serodiagnosis. To this end, a bibliographic survey was conducted on the PubMed platform using the keyword "peptide" or "epitope" combined with "Chagas disease" or "Trypanosoma cruzi"; "diagno*" or "serodiagnosis" or "immunodiagnosis", without period restriction. An increasing number of publications on studies employing peptides in ELISA and rapid tests assays was verified, which confirms the expansion of research in this field. It is possible to observe that many of the peptides tested so far originate from proteins widely used in the diagnosis of Chagas, and many of them are part of commercial tests developed. In this sense, as expected, promising results were obtained for several peptides when tested in ELISA, as many of them exhibited sensitivity and specificity values above 90%. Furthermore, some peptides have been tested in several studies, confirming their diagnostic potential. Despite the promising results observed, it is possible to emphasize the need for extensive testing of peptides, using different serological panels, in order to confirm their potential. The importance of producing an effective assay capable of detecting the clinical stages of the disease, as well as new immunogenic antigens that enable new serological diagnostic tools for Chagas disease, is evident.
Assuntos
Doença de Chagas , Ensaio de Imunoadsorção Enzimática , Peptídeos , Trypanosoma cruzi , Doença de Chagas/diagnóstico , Doença de Chagas/imunologia , Doença de Chagas/sangue , Humanos , Trypanosoma cruzi/imunologia , Peptídeos/imunologia , Peptídeos/química , Ensaio de Imunoadsorção Enzimática/métodos , Testes Imunológicos/métodos , Antígenos de Protozoários/imunologia , Antígenos de Protozoários/sangue , Testes Sorológicos/métodosRESUMO
BACKGROUND: The colorectal cancer (CRC) screening program B-PREDICT is a population based invited two stage screening project using a faecal immunochemical test (FIT) for initial screening followed by a colonoscopy for those with a positive FIT. B-PREDICT was compared with the opportunistic screening colonoscopy (OPP-COL), performed in course of the nationwide screening program. METHODS: Within B-PREDICT all residents of the Austrian federal state Burgenland, aged between 40 and 80 are annually invited to FIT testing. All individuals who underwent initial colonoscopy in Burgenland between 01/2003 and 12/2014, were included in this study. Individuals from the FIT-triggered invited screening program B-PREDICT were compared with those from the non-FIT triggered OPP-COL. RESULTS: 15 133 individuals from B-PREDICT were compared to 10 045 individuals with OPP-COL. CRC detection rates were 1.34% (CI-95%, [1.15; 1.52]) in B-PREDICT compared to 0.54% in OPP-COL (95%-CI, [0.39; 0.68] p < 0.001). The decrease in the age standardized incidence rates of CRC was more pronounced in the population screened with FIT than in the general population screened with colonoscopy. Changes in incidence rates per year were -4.4% (95%-CI, [-5.1; -3.7]) vs. -1.8% (95%-CI, [-1.9; -1.6] p < 0.001). CONCLUSIONS: B-PREDICT shows a two-fold higher detection rate of CRC as well as HRA compared to OPP-COL.
Assuntos
Colonoscopia , Neoplasias Colorretais , Detecção Precoce de Câncer , Sangue Oculto , Humanos , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/prevenção & controle , Neoplasias Colorretais/epidemiologia , Colonoscopia/estatística & dados numéricos , Detecção Precoce de Câncer/métodos , Detecção Precoce de Câncer/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Idoso , Feminino , Adulto , Áustria/epidemiologia , Idoso de 80 Anos ou mais , Incidência , Programas de Rastreamento/métodos , Testes Imunológicos/métodos , Fezes/químicaRESUMO
COVID-19 is a global pandemic caused by the highly infectious SARS-CoV-2 virus. Efforts to combat SARS-CoV-2 infection include mass vaccination and development of monoclonal and convalescent plasma therapeutics that require precise measurements of correlative, functional neutralizing antibodies that prevent virus infection. Developing rapid, safe, easy-to-use, and high-quality neutralization assays are essential for the success of the massive effort. Here, we developed a vesicular stomatitis virus-based neutralization assay that was capable of quantifying varying degrees of neutralization in patient serum samples. This assay has two detection readouts, flow cytometry and live cell imaging. The two readout methods produced consistent values of all 50% neutralization titers, further enhancing measurement confidence on the assay. Moreover, the use of available reference standards such as the World Health Organization International Standard (NIBSC code 20/136) enables quantification and standardization of the pseudovirus neutralization assay with neutralizing antibody titers measured in International Units/mL. Quantitative and standardized neutralization assays are critical for reliable efficacy evaluation and comparison of numerous vaccines and therapeutics.
Assuntos
COVID-19 , Humanos , SARS-CoV-2 , Soroterapia para COVID-19 , Testes Imunológicos , Citometria de Fluxo , Anticorpos Neutralizantes , Anticorpos Antivirais , Testes de Neutralização , Glicoproteína da Espícula de CoronavírusRESUMO
T cells specific for a single antigen tend to be rare, even after expansion of memory cells. They are commonly detected by in vitro stimulation with peptides or protein, followed by staining for intracellular cytokines. In this protocol, CyTOF® mass cytometry is used to collect single-cell data on a large number of cytokines/chemokines, as well as cell-surface proteins that characterize T cells and other immune cells. A method for magnetic bead enrichment of antigen-stimulated T cells, based on their expression of CD154 and CD69, is also included. Coupling magnetic enrichment with highly multiparameter mass cytometry, this method enables the ability to dissect the frequency, phenotype, and function of antigen-specific T cells in greater detail than previously possible. Rare cell subsets can be examined, while minimizing run times on the CyTOF.
Assuntos
Antígenos , Linfócitos T , Citometria de Fluxo/métodos , Testes Imunológicos , Citocinas/metabolismoRESUMO
The diagnosis of extrapulmonary tuberculosis (EPTB) poses a significant challenge, with controversies surrounding the accuracy of IFN-γ release assays (IGRAs). This study aimed to assess the diagnostic accuracy of RD1 immunodominant T-cell antigens, including ESAT-6, CFP-10, PE35, and PPE68 proteins, for immunodiagnosis of EPTB. Twenty-nine patients with EPTB were enrolled, and recombinant PE35, PPE68, ESAT-6, and CFP-10 proteins were evaluated in a 3-day Whole Blood Assay. IFN-γ levels were measured using a Human IFN-γ ELISA kit, and the QuantiFERON-TB Gold Plus (QFT-Plus) test was performed. Predominantly, the patients were of Afghan (62%, n = 18) and Iranian (38%, n = 11) nationalities. Eighteen individuals tested positive for QFT-Plus, accounting for 62% of the cases. The positivity rate for IGRA, using each distinct recombinant protein (ESAT-6, PPE68, PE35, and CFP-10), was 72% (n = 21) for every protein tested. Specifically, among Afghan patients, the positivity rates for QFT-Plus and IGRA using ESAT-6, PPE68, PE35, and CFP-10 were 66.7%, 83.3%, 83.3%, 77.8%, and 88.9%, respectively. In contrast, among Iranian patients, the positivity rates for the same antigens were 54.5%, 54.5%, 54.5%, 63.6%, and 45.5%, respectively. In conclusion, our study highlights the potential of IGRA testing utilizing various proteins as a valuable diagnostic tool for EPTB. Further research is needed to elucidate the underlying factors contributing to these disparities and to optimize diagnostic strategies for EPTB in diverse populations.
Assuntos
Mycobacterium tuberculosis , Tuberculose Extrapulmonar , Humanos , Antígenos de Bactérias , Epitopos Imunodominantes , Irã (Geográfico) , Linfócitos T , Testes ImunológicosRESUMO
BACKGROUND: The aim of this study was to verify the analytical performance of the UD90DT electrochemiluminescence immunoassay system (the UD90DT system) for measuring high-sensitivity cardiac troponin T (hs-cTnT). METHODS: According to the Clinical and Laboratory Standards Institute guidelines, the imprecision, linearity, reference interval, limit of blank (LoB), limit of detection (LoD), and functional sensitivity (FS) of hs-cTnT using the UD90DT system were verified. The trueness was validated using the Proficiency Testing (PT) materials. RESULTS: The within-run and between-run coefficients of variations (CVs) of two hs-cTnT levels were 7.2% and 1.5%, and 7.1% and 2.6%, respectively. The biases of the PT samples (n = 6) all fell within the allowable total error. The linearity satisfied the requirements, with a slope of 0.9963 and an R12 value of 0.9998. The hs-cTnT levels of the healthy volunteers (n = 20) ranged from 3.0 ng/L to 7.7 ng/L. All blank calibrator measurements (n = 20) fell within the LoD claim, and none of the samples (n = 25) had a LoB value ≤ 3.0 ng/L. The FS was 5.3 ng/L. Furthermore, a good correlation between the UD90DT system and the Cobas e 601 module was observed for hs-cTnT. CONCLUSIONS: The analytical performance of hs-cTnT using the UD90DT system is acceptable and satisfies clinical needs.
Assuntos
Testes Imunológicos , Troponina T , Humanos , Limite de Detecção , Imunoensaio , BiomarcadoresRESUMO
SUMMARYThe emergence and worldwide dissemination of SARS-CoV-2 required both urgent development of new diagnostic tests and expansion of diagnostic testing capacity on an unprecedented scale. The rapid evolution of technologies that allowed testing to move out of traditional laboratories and into point-of-care testing centers and the home transformed the diagnostic landscape. Four years later, with the end of the formal public health emergency but continued global circulation of the virus, it is important to take a fresh look at available SARS-CoV-2 testing technologies and consider how they should be used going forward. This review considers current use case scenarios for SARS-CoV-2 antigen, nucleic acid amplification, and immunologic tests, incorporating the latest evidence for analytical/clinical performance characteristics and advantages/limitations for each test type to inform current debates about how tests should or should not be used.
Assuntos
Teste para COVID-19 , COVID-19 , SARS-CoV-2 , Humanos , COVID-19/diagnóstico , SARS-CoV-2/imunologia , Teste para COVID-19/métodos , Técnicas de Amplificação de Ácido Nucleico/métodos , Antígenos Virais/imunologia , Antígenos Virais/análise , Teste de Ácido Nucleico para COVID-19/métodos , Testes Imunológicos/métodosRESUMO
Background: Omalizumab is approved for the treatment of chronic spontaneous urticaria (CSU) that is refractory to antihistamines. Total immunoglobulin E (IgE) levels have emerged as a possible biomarker to predict response to omalizumab. However, the existing literature is heterogenous, with conflicting conclusions with regard to the role of total IgE levels. Objective: We sought to clarify the role of evaluating total IgE levels in patients with CSU by performing a meta-analysis on the existing literature to determine if meaningful changes exist between responders and nonresponders to omalizumab. Methods: A total of 68 unique citations were returned and screened by two independent reviewers. Editorials, reviews, and case reports were excluded, and a total of 33 original articles were identified and underwent secondary evaluation. Studies that present mean ± standard deviation total IgE levels and/or 95% confidence intervals (CI) were included, whereas studies with < 25 subjects were excluded. Three studies ultimately met these criteria. Results: We found a mean difference in total IgE levels between those who responded to omalizumab versus those without a response of 49.76 (95% CI, 7.13-92.38; p = 0.02), which demonstrated higher mean IgE values in responders compared with nonresponders. Conclusion: This study presents additional evidence that supports evaluation of total IgE levels as it pertains to response to omalizumab therapy in CSU. When considering the current evidence, it seems reasonable to consider the baseline total IgE level as a biomarker to predict the treatment response to omalizumab. Based on the existing literature, we cannot conclude at what threshold nonresponse is more likely to occur.
Assuntos
Urticária Crônica , Omalizumab , Humanos , Omalizumab/uso terapêutico , Urticária Crônica/tratamento farmacológico , Biomarcadores , Testes Imunológicos , Imunoglobulina ERESUMO
BACKGROUND: A next-generation multitarget stool DNA test, including assessments of DNA molecular markers and hemoglobin level, was developed to improve the performance of colorectal cancer screening, primarily with regard to specificity. METHODS: In a prospective study, we evaluated a next-generation multitarget stool DNA test in asymptomatic adults 40 years of age or older who were undergoing screening colonoscopy. The primary outcomes were sensitivity of the test for colorectal cancer and specificity for advanced neoplasia (colorectal cancer or advanced precancerous lesions). Advanced precancerous lesions included one or more adenomas or sessile serrated lesions measuring at least 1 cm in the longest dimension, lesions with villous histologic features, and high-grade dysplasia. Secondary objectives included the quantification of sensitivity for advanced precancerous lesions and specificity for nonneoplastic findings or negative colonoscopy and comparison of sensitivities for colorectal cancer and advanced precancerous lesions between the multitarget stool DNA test and a commercially available fecal immunochemical test (FIT). RESULTS: Of 20,176 participants, 98 had colorectal cancer, 2144 had advanced precancerous lesions, 6973 had nonadvanced adenomas, and 10,961 had nonneoplastic findings or negative colonoscopy. With the next-generation test, sensitivity for colorectal cancer was 93.9% (95% confidence interval [CI], 87.1 to 97.7), and specificity for advanced neoplasia was 90.6% (95% CI, 90.1 to 91.0). Sensitivity for advanced precancerous lesions was 43.4% (95% CI, 41.3 to 45.6), and specificity for nonneoplastic findings or negative colonoscopy was 92.7% (95% CI, 92.2 to 93.1). With the FIT, sensitivity was 67.3% (95% CI, 57.1 to 76.5) for colorectal cancer and 23.3% (95% CI, 21.5 to 25.2) for advanced precancerous lesions; specificity was 94.8% (95% CI, 94.4 to 95.1) for advanced neoplasia and 95.7% (95% CI, 95.3 to 96.1) for nonneoplastic findings or negative colonoscopy. As compared with FIT, the next-generation test had superior sensitivity for colorectal cancer (P<0.001) and for advanced precancerous lesions (P<0.001) but had lower specificity for advanced neoplasia (P<0.001). No adverse events occurred. CONCLUSIONS: The next-generation multitarget stool DNA test showed higher sensitivity for colorectal cancer and advanced precancerous lesions than FIT but also showed lower specificity. (Funded by Exact Sciences; BLUE-C ClinicalTrials.gov number, NCT04144738.).
Assuntos
Adenoma , Neoplasias Colorretais , DNA , Detecção Precoce de Câncer , Fezes , Imunoquímica , Lesões Pré-Cancerosas , Adulto , Humanos , Adenoma/diagnóstico , Neoplasias Colorretais/diagnóstico , DNA/análise , Detecção Precoce de Câncer/métodos , Fezes/química , Lesões Pré-Cancerosas/diagnóstico , Estudos Prospectivos , Doenças Assintomáticas , Colonoscopia , Sensibilidade e Especificidade , Testes Imunológicos/métodos , Imunoquímica/métodosRESUMO
Ocular toxoplasmosis (OT) is caused by protozoan T. gondii. Ophthalmological examination is considered the gold standard for OT diagnosis, and laboratory tests are used for diagnostic confirmation. However, these tests can present different results, which change depending on their basis, on sample type and on patients' clinical alteration. Thus, the aim of the present study is to assess immunodiagnostic and molecular techniques applied in blood, serum and tear fluid to diagnose T. gondii infection in patients seen at an Ophthalmology Clinic. In total, 160 patients were included in the study, 40 of them had OT with active lesions (G1); 40 had OT with healed lesions (G2), 40 had non-toxoplasmic uveitis (G3) and 40 had no ocular alterations (G4). Serum samples were subjected to Immunoenzymatic Assay (ELISA) and to Indirect Immunofluorescence Reaction (IFAT) to search for anti-T. gondii IgM and IgG. Tear fluid samples were analyzed through ELISA for IgA research. All blood and tear fluid samples were subjected to conventional polymerase chain reaction (cPCR) and in a Nested PCR model for T. gondii DNA amplification with targets B1, GRA7 and REP 529. IgG and IgM anti-T. gondii was detected in serum samples from 106 and 15 patients, respectively, when combining ELISA and IFAT results. Anti-T.gondii IgA antibodies were detected in 9.2% of the tear material. Nested PCR with GRA7 target showed higher positivity in blood samples (24.4%); Nested PCR with B1 target showed a higher frequency of positivity in tears (15%). Biological samples of patients with active lesions showed the highest positivity frequencies in all immunodiagnostic assays, as well as in most PCR models. The present results highlighted the need of associating techniques with different fundamentals to confirm OT diagnosis. Furthermore, further tear fluid analyses should be performed to validate this biological material as lesser invasive alternative for the more accurate OT diagnosis.
Assuntos
Toxoplasma , Toxoplasmose Ocular , Humanos , Brasil , Anticorpos Antiprotozoários , Testes Imunológicos , Imunoglobulina G , Imunoglobulina M , Imunoglobulina A/análiseRESUMO
BACKGROUND: The advent of lateral flow devices (LFDs) for SARS-CoV-2 detection enabled widespread use of rapid self-tests during the pandemic. While self-testing using LFDs is now common, whether self-testing provides comparable performance to professional testing was a key question that remained important for pandemic planning. METHODS: Three prospective multi-centre studies were conducted to compare the performance of self- and professional testing using LFDs. Participants tested themselves or were tested by trained (professional) testers at community testing sites in the UK. Corresponding qRT-PCR test results served as reference standard. The performance of Innova, Orient Gene and SureScreen LFDs by users (self) and professional testers was assessed in terms of sensitivity, specificity, and kit failure (void) rates. Impact of age, sex and symptom status was analysed using logistic regression modelling. RESULTS: 16,617 participants provided paired tests, of which 15,418 were included in the analysis. Self-testing with Innova, Orient Gene or SureScreen LFDs achieved sensitivities of 50 %, 53 % or 72 %, respectively, compared to qRT-PCR. Self and professional LFD testing showed no statistically different sensitivity with respect to corresponding qRT-PCR testing. Specificity was consistently equal to or higher than 99 %. Sex and age had no or only marginal impact on LFD performance while sensitivity was significantly higher for symptomatic individuals. Sensitivity of LFDs increased strongly to up to 90 % with higher levels of viral RNA measured by qRT-PCR. CONCLUSIONS: Our results support SARS-CoV-2 self-testing with LFDs, especially for the detection of individuals whose qRT-PCR tests showed high viral concentrations.
Assuntos
COVID-19 , Humanos , COVID-19/diagnóstico , Estudos Prospectivos , SARS-CoV-2 , Testes Imunológicos , Reino Unido , Sensibilidade e EspecificidadeRESUMO
Cerebrospinal fluid (CSF) isoelectrofocusing (IEF) is considered as the gold standard for detecting an intrathecal synthesis of IgG, which is a hallmark of multiple sclerosis (MS). This corresponds to the presence of CSF-restricted IgG oligoclonal bands (OCB) (typically type 2 pattern). Moreover, this technique can also detect a systemic immune reaction with passive transfer of IgG (type 3 and 4 patterns) for which the clinical relevance is less understood. The aim of our study was to determine the frequency and disease associations of IEF type 3 and 4 patterns and to investigate the potential usefulness of including quantitative data (IgG index and Reiber Diagram) in interpreting such IEF profiles. Among 544 patients who underwent CSF IEF (Hydragel CSF isofocusing kit, Sebia®, France) in our Laboratory during a six-year-period, those who presented type 3 or 4 patterns were selected. Clinical data and results of other immunological tests were analyzed for 27 patients followed in the Neurological Department. Frequencies of type 3 and type 4 patterns were relatively low (2.3 % and 3.4 % respectively). Among patients with type 3 pattern included in our study (n = 10), 5 were diagnosed with MS. For the 5 other patients, the diagnosis was a clinically isolated syndrome (CIS) (2 cases), a probable auto-immune encephalitis (2 cases) and a possible genetic neurodegenerative disease (1 case). MS patients had an IgG index >0.7 and fell into area 4 of Reiber diagram while non-MS patients had an IgG index <0.7 and fell into area 1, except the last case. Regarding type 4 pattern (n = 17), the diagnoses were as follows: MS (3), CIS (4), Neuromyelitis optica spectrum disorders with positive anti-AQP4 antibodies (3) and anti-NMDAR autoimmune encephalitis (1). The remaining cases had central nervous system impairment related to vascular, metabolic or tumoral etiologies (3) or peripheral nervous system impairment (3). In this group (type 4 pattern), IgG index was <0.7 in 15/17 cases. Interpretation using Reiber diagram showed an abnormal blood-brain barrier for 8/17 patients. Type 3 and 4 IEF patterns are infrequently observed in routine neurology practice. It is important for the diagnostic laboratory professional as well as for the neurologist to understand their clinical relevance. Our findings highlight the contribution of quantitative evaluation of CSF (IgG index, Reiber diagram) for the interpretation of such situations. Despite the small size of our study population, our results emphasize the importance of reporting the exact type of IEF pattern and not only the positivity or not of OCB.
Assuntos
Encefalite Antirreceptor de N-Metil-D-Aspartato , Esclerose Múltipla , Doenças Neurodegenerativas , Humanos , Relevância Clínica , Imunoglobulina G/líquido cefalorraquidiano , Bandas Oligoclonais/líquido cefalorraquidiano , Testes ImunológicosRESUMO
BACKGROUND AND AIM: Primary biliary cholangitis (PBC) is a chronic autoimmune cholangiopathy, characterized by the presence of some autoantibodies in the serum. This study aimed to evaluate the clinical significance of AMA-M2, anti-gp210 and anti-sp100 antibody levels detected by multiplex bead-based flow fluorescent immunoassay (MBFFI) in PBC. METHODS: This study cohort included 238 PBC patients, 81 autoimmune hepatitis (AIH) patients, 62 systemic lupus erythematosus (SLE) patients, and 118 healthy controls. Serum AMA-M2, anti-gp210 and anti-sp100 antibody were detected by MBFFI and immunoblotting assay (IBT). The relationship between three antibody levels and cirrhosis, liver function, cholestasis markers and therapeutic effect to ursodesoxycholic acid (UDCA) was evaluated in PBC. RESULTS: MBFFI were presented good coincidence rate (87.39%-95.38%) with IBT. The level of AMA-M2, anti-gp210 and anti-sp100 antibodies in PBC patients were higher than other disease group and healthy controls (p ï¼ .01). When compared with the healthy controls group, the AUC of AMA-M2, anti-gp210 and anti-sp100 antibodies were 0.9245, 0.7619, and 0.6789, respectively. In addition, gp210 antibody levels have diagnostic value in patients with liver cirrhosis (AUC: 0.7567). We found that when combine detect these three antibodies, the sensitivity was higher than individually detection. High level of serum anti-gp210 antibody could be related to worse liver function and more severe cholestasis in PBC patients. Moreover, serum antibody levels may decrease or remained flat in patients who responded well to UDCA. CONCLUSION: The detection of AMA-M2, anti-gp210 and anti-sp100 antibody levels by MBFFI showed good performance in the diagnosis of PBC. Serum anti-gp210 antibody level is related to cirrhosis, poor liver function and severe cholestasis in PBC.
Assuntos
Colestase , Cirrose Hepática Biliar , Humanos , Cirrose Hepática Biliar/diagnóstico , Testes Imunológicos , Autoanticorpos , Fatores de Transcrição , ImunoensaioRESUMO
In vivo and in vitro experiments have been used to investigate the effect of drugs, chemical agents, growth factors, vitamins, etc., on embryonic development. Alternative tests have been developed to determine whether drugs or other compounds have toxic or teratogenic effects on a particular organ or tissue. The rat whole embryo culture method is useful for studying the mechanism of normal embryo development. The explanted rat conceptuses grow in the culture environment at the same rate as in utero development. Furthermore, the considerable advantage of explanting rat embryos is that it allows direct observation of embryogenesis. The rat whole embryo culture is run by explanting rat embryos on gestation day 9.5 for rats. The conceptuses are then cultured on a rotating platform in a mixture of culture medium with appropriate gassing for 48 hours. The maternal serum is used as the culture medium, and chemicals or other agents to be evaluated separately are added to this medium. At the end of the culture period, growth and development of the embryos are evaluated morphologically.