Design of a Chimaeric Antigen And Its Use In The Detection of IgG Antibodies Against Rubella Virus

Abstract Background: Rubella virus (RV) is the causative agent of rubella or German measles. Although most infections cause only mild self-limited measles-like illness, the infection in pregnant women can cause severe foetal malformation or even miscarriage, especially in the first 3 months of pregnancy. Therefore, it is of great practical significance to establish a simple and sensitive RV detection method.Methods: The partial epitopes of the E1 and E2 proteins from Rubella Virus were selected as the target sites, the sequence of the selected antigenic sites of the E1 and E2 were linked by a linker. The expression plasmid P6T was constructed by inserting the gene into PET-32A + with a His tag. The P6 protein was induced and expressed in Escherichia coli L21 DE3 and purified by nickel column affinity. The protein P6 antigen was identified by Western blotting, and an anti-P6 antibody ELISA was established to test known serum samples to evaluate the capability of this method.Results: After purification, the concentration and purity of the protein P6 were 0.283 mg/mL and more than 80%, respectively. Western blotting showed that the protein P6 could react with rubella virus positive serum. By ELISA, 36 negative sera and 58 positive sera were detected. The coincidence rate, specificity and sensitivity of the ELISA were 88.89%, 84.48% and 84.48%, respectively. The P6 ELISA with a kappa coefficient of 0.709, P<0.05, indicated excellent consistency.Conclusions: The P6 protein with excellent antigenicity obtained from prokaryotic expression followed by chromatography purification could prove useful for early diagnosis of RV infection.

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An enzyme-linked immunosorbent assay for the detection of IgG antibodies against Babesia equi in horses

Ciência Rural ◽

10.1590/s0103-84782004000500031 ◽

2004 ◽

Vol 34 (5) ◽

pp. 1525-1529 ◽

Cited By ~ 12

Author(s):

Cristiane Divan Baldani ◽

Rosangela Zacarias Machado ◽

Paulo de Tarso Landgraf Botteon ◽

Felipe Santoro Takakura ◽

Carlos Luiz Massard

Keyword(s):

Immunosorbent Assay ◽

Serological Test ◽

Epidemiological Studies ◽

Sao Paulo ◽

Enzyme Linked Immunosorbent Assay ◽

São Paulo ◽

Igg Antibodies ◽

Serum Samples ◽

Babesia Equi ◽

Specificity And Sensitivity

A crude antigenic preparation of Babesia equi was used to develop and establish the suitability of an enzyme-linked immunosorbent assay (ELISA) for the detection of parasite carriers. Optimal dilutions of the antigen, using positive and negative reference sera, were determined by checkboard titrations. The specificity and sensitivity of the ELISA were 100 %. A total of 90 serum samples were taken from horses from the Northeast region of São Paulo State and examined for diagnosis of equine B. equi infection by ELISA. Approximately 75% (n=67) of all the horses tested were found serologically positive for B. equi. These results suggest that the ELISA described may prove to be an appropriate serological test for epidemiological studies on B. equi infections in the field and that equine piroplasmosis is a cause for serious concern in the State of São Paulo, Brazil.

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ELISA and Western Blotting tests in the detection of IgG antibodies to Taenia solium metacestodes in serum samples in human neurocysticercosis

Tropical Medicine & International Health ◽

10.1046/j.1365-3156.2000.00567.x ◽

2000 ◽

Vol 5 (6) ◽

pp. 443-449 ◽

Cited By ~ 25

Author(s):

Kely Yoshiko Martins Shiguekawa ◽

Jose Roberto Mineo ◽

Leandro Pajuaba Moura ◽

Julia Maria Costa-Cruz

Keyword(s):

Western Blotting ◽

Taenia Solium ◽

Igg Antibodies ◽

Serum Samples

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The use of single-radial-haemolysis for rubella antibody studies

Journal of Hygiene ◽

10.1017/s0022172400053195 ◽

1977 ◽

Vol 79 (3) ◽

pp. 355-364 ◽

Cited By ~ 20

Author(s):

Mairin Clarke ◽

Janet Boustred ◽

Valerie Seagroatt ◽

G. C. Schild

Keyword(s):

Rubella Virus ◽

Close Correlation ◽

Assay Method ◽

Igg Antibodies ◽

Serum Samples ◽

Immuno Globulins ◽

Haemolysis Test ◽

Rubella Antibody

SUMMARYThe use of a single-radial-haemolysis technique for the detection of antibody to rubella virus is described. The single-radial-haemolysis test was compared with the standard HI methods for the detection of antibody to rubella virus. A close correlation between the two methods was observed in a survey of over two thousand serum samples and the study indicated that single-radial-haemolysis was highly satisfactory as an assay method for IgG antibodies to rubella virus. It was found that the immuno-globulins active in SRH tests sedimented in the 7S range in sucrose rate gradients and were presumably immunoglobulins of the IgG class, but 19S iinmunoglobulins did not produce haemolysis.

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Immunoglobulin (Ig)A seropositivity against SARS-CoV-2 in healthcare workers in Israel, 4 April to 13 July 2020: an observational study

Eurosurveillance ◽

10.2807/1560-7917.es.2021.26.48.2001690 ◽

2021 ◽

Vol 26 (48) ◽

Author(s):

Yaniv Lustig ◽

Carmit Cohen ◽

Asaf Biber ◽

Hanaa Jaber ◽

Yael Becker Ilany ◽

...

Keyword(s):

Healthcare Workers ◽

Significant Risk ◽

Igg Antibodies ◽

Exposure Risk ◽

Serum Samples ◽

Igg Antibody ◽

High Exposure ◽

Iga Antibodies ◽

Iga Response ◽

Antibody Elisa

Introduction The COVID-19 pandemic has put healthcare workers (HCW) at significant risk. Presence of antibodies can confirm prior severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Aim This study investigates the prevalence of IgA and IgG antibodies against SARS-CoV-2 in HCW. Methods Performance of IgA and IgG antibody ELISA assays were initially evaluated in positive and negative SARS-CoV-2 serum samples. IgA and IgG antibodies against SARS-CoV-2 were measured in 428 asymptomatic HCW. We assessed the risk of two groups: HCW with high exposure risk outside work (HROW) residing in areas where COVID-19 was endemic (n = 162) and HCW with high exposure risk at work (HRAW) in a COVID-19 intensive care unit (ICU) (n = 97). Results Sensitivities of 80% and 81.2% and specificities of 97.2% and 98% were observed for IgA and IgG antibodies, respectively. Of the 428 HCW, three were positive for IgG and 27 for IgA. Only 3/27 (11%) IgA-positive HCW had IgG antibodies compared with 50/62 (81%) in a group of previous SARS-CoV-2-PCR-positive individuals. Consecutive samples from IgA-positive HCW demonstrated IgA persistence 18–83 days in 12/20 samples and IgG seroconversion in 1/20 samples. IgA antibodies were present in 8.6% of HROW and 2% of HRAW. Conclusions SARS-CoV-2 exposure may lead to asymptomatic transient IgA response without IgG seroconversion. The significance of these findings needs further study. Out of work exposure is a possible risk of SARS-CoV-2 infection in HCW and infection in HCW can be controlled if adequate protective equipment is implemented.

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Faculty Opinions recommendation of Sensitivity and specificity of a new commercial enzyme-linked immunoassay kit for detecting Entamoeba histolytica IgG antibodies in serum samples.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.1029752.346563 ◽

2005 ◽

Author(s):

Nitaya Thammapalerd

Keyword(s):

Sensitivity And Specificity ◽

Entamoeba Histolytica ◽

Igg Antibodies ◽

Serum Samples ◽

Commercial Enzyme

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Sphingolipid Analysis Indicate Lactosylceramide as a Potential Biomarker of Inflammatory Bowel Disease in Children

Biomolecules ◽

10.3390/biom10071083 ◽

2020 ◽

Vol 10 (7) ◽

pp. 1083

Author(s):

Aleksandra Filimoniuk ◽

Agnieszka Blachnio-Zabielska ◽

Monika Imierska ◽

Dariusz Marek Lebensztejn ◽

Urszula Daniluk

Keyword(s):

Inflammatory Bowel Disease ◽

Bowel Disease ◽

High Performance ◽

Area Under The Curve ◽

Study Groups ◽

Diagnostic Value ◽

Serum Samples ◽

Specificity And Sensitivity ◽

Potential Biomarker ◽

Inflammatory Bowel

An altered ceramide composition in patients with inflammatory bowel disease (IBD) has been reported recently. The aim of this study was to evaluate the concentrations of sphingolipids in the serum of treatment-naive children with newly diagnosed IBD and to determine the diagnostic value of the tested lipids in pediatric IBD. The concentrations of sphingolipids in serum samples were evaluated using a quantitative method, an ultra-high-performance liquid chromatography-tandem mass spectrometry in children with Crohn’s disease (CD) (n=34), ulcerative colitis (UC) (n = 39), and controls (Ctr) (n = 24). Among the study groups, the most significant differences in concentrations were noted for C16:0-LacCer, especially in children with CD compared to Ctr or even to UC. Additionally, the relevant increase in C20:0-Cer and C18:1-Cer concentrations were detected in both IBD groups compared to Ctr. The enhanced C24:0-Cer level was observed only in UC, while C18:0-Cer only in the CD group. The highest area under the curve (AUC), specificity, and sensitivity were determined for C16:0-LacCer in CD diagnosis. Our results suggest that the serum LacC16-Cer may be a potential biomarker that distinguishes children with IBD from healthy controls and differentiates IBD subtypes. In addition, C20:0-Cer and C18:0-Cer levels also seem to be closely connected with IBD.

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Luminex Multiplex Bead Assay Monitoring HLA IgG Antibodies in Sensitized Pre- and Post-transplant Patients: Clonality of the Detection Antibody Impacts Specificity and Sensitivity

Applied Sciences ◽

10.3390/app11146430 ◽

2021 ◽

Vol 11 (14) ◽

pp. 6430

Author(s):

Mepur H. Ravindranath ◽

Narendranath M. Ravindranath ◽

Carly J. Amato-Menker

Keyword(s):

Igg Antibodies ◽

Fluorescent Intensity ◽

Heavy Chains ◽

Transplant Patients ◽

Specificity And Sensitivity ◽

Single Antigen ◽

Two Factors ◽

Specific Igg ◽

End Stage ◽

Multiplex Bead

The number and the binding affinity, measured as the mean fluorescent intensity (MFI) of HLA-specific IgG antibodies, formed in the sera of end-stage organ disease patients and allograft recipients, referred to as sensitization, may restrict the availability of a donor organ and/or lead to graft failure after transplantation. The MFI of HLA Abs in sera is monitored with the Luminex-based single-antigen bead (SAB) immunoassay. The following two factors may impact the reliable measurement of MFI: one, the HLA structural variants on the SAB, namely, trimeric HLA (closed conformers, CC) and monomeric heavy chains (open conformers, OC); and two, the nature of the detection Abs, namely, IgG heavy-chain binding polyclonal-Fab (IgHPolyFab) or Fc-binding monoclonal-IgG (FcMonoIgG). Anti-CC Abs correlate with positive flow cross-matches, and are considered to be pathogenic and damaging to the graft, whereas anti-OC Abs appear to have little relevance to graft attrition. The presence of both CC and OC on beads may impair the reliability of monitoring the nature and MFI of pathogenic Abs. Our objective is to compare the MFI of the HLA Abs in the sera of 20 sensitized patients in two different SAB assays, with the two detection Abs. Our data reveal that the admixture of OC with CC on beads will affect the reliability of the measurement of the pathogenic Abs, and that FcMonoIgG is the more sensitive and specific detection Ab for the accurate assessment of HLA sensitization.

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Serum MicroRNA Signature as a Diagnostic and Therapeutic Marker in Patients with Psoriatic Arthritis

The Journal of Rheumatology ◽

10.3899/jrheum.190602 ◽

2020 ◽

Vol 47 (12) ◽

pp. 1760-1767

Author(s):

Sarah M. Wade ◽

Trudy McGarry ◽

Siobhan C. Wade ◽

Ursula Fearon ◽

Douglas J. Veale

Keyword(s):

Psoriatic Arthritis ◽

Characteristic Curve ◽

High Specificity ◽

Serum Samples ◽

Rna Molecules ◽

Serum Mirna ◽

Serum Microrna ◽

Specificity And Sensitivity ◽

European League Against Rheumatism ◽

Noninvasive Markers

ObjectiveMicroRNA (miRNA) are small endogenous regulatory RNA molecules that have emerged as potential therapeutic targets and biomarkers in autoimmunity. Here, we investigated serum miRNA levels in patients with psoriatic arthritis (PsA) and further assessed a serum miRNA signature in therapeutic responder versus nonresponder PsA patients.MethodsSerum samples were collected from healthy controls (HC; n = 20) and PsA patients (n = 31), and clinical demographics were obtained. To examine circulatory miRNA in serum from HC and PsA patients, a focused immunology miRNA panel was analyzed utilizing a miRNA Fireplex assay (FirePlex Bioworks Inc.). MiRNA expression was further assessed in responders versus nonresponders according to the European League Against Rheumatism response criteria.ResultsSix miRNA (miR-221-3p, miR-130a-3p, miR-146a-5p, miR-151-5p, miR-26a-5p, and miR-21-5p) were significantly higher in PsA compared to HC (all P < 0.05), with high specificity and sensitivity determined by receiver-operating characteristic curve analysis. Analysis of responder versus nonresponders demonstrated higher baseline levels of miR-221-3p, miR-130a-3p, miR-146a-5p, miR-151-5p, and miR-26a-5p were associated with therapeutic response.ConclusionThis study identified a 6-serum microRNA signature that could be attractive candidates as noninvasive markers for PsA and may help to elucidate the disease pathogenesis.

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