scholarly journals Establishment of the diagnostic cut-off points for levels of serum antibodies to pertussis toxin in adults in Poland

2018 ◽  
pp. 139-147
Author(s):  
Waldemar Rastawicki ◽  
Natalia Rokosz-Chudzial ◽  
Karolina Śmietańska ◽  
Anna Chróst ◽  
Urszula Roguska
Keyword(s):  
Pertussis Toxin ◽  
Blood Donors ◽  
Adult Population ◽  
Arithmetic Mean ◽  
Igg Antibodies ◽  
Serum Samples ◽  
International Standard ◽  
Iga Antibodies ◽  
Antibody Levels ◽  
Serology Testing

Introduction: Standardization of ELISA tests for the diagnosis of infections caused by B. pertussis remains challenging despite efforts to improve it. It is recommended that serology testing should use purified pertussis toxin as the only coating antigen and that concentration of antibodies should be expressed in international units per mL (IU/ml) according to the First WHO International Standard for Pertussis Antiserum. However, available commercial ELISAs are often of different antigen composition and quality and sometimes do not calculate antibody levels in IU/ml. Furthermore, for single-sample serology, various cut-off values for IgG- and IgA-anti pertussis toxin in different EU reference laboratories have been proposed. The aim of this study was to establish of the diagnostic cut-off points for levels of serum IgG and IgA antibodies to pertussis toxin in adults in Poland and determine the seroprevalence of these antibodies among Polish blood donors. Materials and Methods: The IgG and IgA antibodies in serum samples collected from 236 blood donors were measured by in-house ELISA with purified pertussis toxin as antigen (0,5 µg/ml). The cut-off value was settled by calculation the OD450 results from all blood donors (arithmetic mean plus 2 standard deviations). Antibody levels were quantitated with respect to the First WHO International Standard for Pertussis Antiserum (06/140) and results were expressed in IU/mL. Results: According to the obtained results, in the case of searching for IgG and IgA antibodies for pertussis toxin, a cut-off of 120 IU/ml and 16 IU/ml respectively, should be taken as diagnostic significant level in the adult population in Poland. A study showed the presence of IgG antibodies at a diagnostic level in 18 (7.6%) samples, and IgA antibodies to pertussis toxin in 14 (5.9%) serum samples obtained from blood donors. Conclusions: The established in our investigation cut-off values for anti-PT IgG and IgA good correspond with values recommended by reference laboratories in other European countries.

scholarly journals Immunoglobulin G and A Antibody Responses to Bacteroides forsythus and Prevotella intermedia in Sera and Synovial Fluids of Arthritis Patients

2003 ◽  
Vol 10 (6) ◽  
pp. 1043-1050 ◽  
Author(s):  
Ketil Moen ◽  
Johan G. Brun ◽  
Tor Magne Madland ◽  
Turid Tynning ◽  
Roland Jonsson
Keyword(s):  
Immune Responses ◽  
Immunoglobulin G ◽  
Enzyme Linked Immunosorbent Assay ◽  
Prevotella Intermedia ◽  
Igg Antibodies ◽  
Serum Samples ◽  
Igg Antibody ◽  
Iga Antibodies ◽  
Iga Antibody ◽  
Antibody Levels

ABSTRACT The objective of the present study was to investigate immunoglobulin G (IgG) and IgA antibody immune responses to Porphyromonas gingivalis, Prevotella intermedia, Bacteroides forsythus, and Candida albicans in the sera of patients with rheumatoid arthritis (RA), the synovial fluid (SF) of patients with RA (RA-SF samples), and the SF of patients without RA (non-RA-SF samples). An enzyme-linked immunosorbent assay was used to determine IgG and IgA antibody levels in 116 serum samples from patients with RA, 52 RA-SF samples, and 43 non-RA-SF samples; and these were compared with those in SF samples from 9 patients with osteoarthritis (OA-SF samples) and the blood from 100 donors (the control [CTR] group). Higher levels of IgG antibodies against B. forsythus (P < 0.0001) and P. intermedia (P < 0.0001) were found in non-RA-SF samples than in OA-SF samples, and higher levels of IgG antibodies against B. forsythus (P = 0.003) and P. intermedia (P = 0.024) were found in RA-SF samples than in OA-SF samples. Significantly higher levels of IgA antibodies against B. forsythus were demonstrated in both RA-SF and non-RA-SF samples than in OA-SF samples. When corrected for total Ig levels, levels of IgG antibody against B. forsythus were elevated in RA-SF and non-RA-SF samples compared to those in OA-SF samples. Lower levels of Ig antibodies against B. forsythus were found in the sera of patients with RA than in the plasma of the CTR group for both IgG (P = 0.003) and IgA (P < 0.0001). When corrected for total Ig levels, the levels of IgG and IgA antibodies against B. forsythus were still found to be lower in the sera from patients with RA than in the plasma of the CTR group (P < 0.0001). The levels of antibodies against P. gingivalis and C. albicans in the sera and SF of RA and non-RA patients were comparable to those found in the respective controls. The levels of IgG and IgA antibodies against B. forsythus were elevated in SF from patients with RA and non-RA-SF samples compared to those in OA-SF samples. Significantly lower levels of IgG and IgA antibodies against B. forsythus were found in the sera of patients with RA than in the plasma of the CTR group. This indicates the presence of an active antibody response in synovial tissue and illustrates a potential connection between periodontal and joint diseases.

scholarly journals Seroprevalence, waning, and correlates of anti-SARS-CoV-2 IgG antibodies in Tyrol, Austria: Large-scale study of 35,193 blood donors conducted between June 2020 and September 2021

2021 ◽  
Author(s):  
Anita Siller ◽  
Lisa Seekircher ◽  
Gregor A Wachter ◽  
Manfred Astl ◽  
Lena Tschiderer ◽  
...  
Keyword(s):  
Large Scale ◽  
Blood Donors ◽  
Participation Rate ◽  
Federal State ◽  
Igg Antibodies ◽  
Serum Samples ◽  
Serological Tests ◽  
Nucleocapsid Proteins ◽  
Antibody Levels ◽  
Prior Infection

Background: There is uncertainty about the seroprevalence of anti-SARS-CoV-2 antibodies in the general population of Austria, and about the extent to which antibodies elicited by vaccination or infection wane over time. Aim: To estimate seroprevalence, waning, and correlates of anti-SARS-CoV-2 IgG antibodies in the Federal State of Tyrol, Austria. Methods: We conducted a seroepidemiological study between June 2020 and September 2021, enrolling blood donors aged 18-70 years across Tyrol, Austria (participation rate 84.0%). We analysed serum samples for antibodies against spike or nucleocapsid proteins of SARS-CoV-2 with Abbott SARS-CoV-2 IgG assays. Results: We performed 47,363 serological tests among 35,193 individuals (median age 43.1 years [IQR: 29.3-53.7], 45.3% women, 10.0% with prior SARS-CoV-2 infection). Seroprevalence increased from 3.4% (95% CI: 2.8-4.2%) in June 2020 to 82.7% (95% CI: 81.4-83.8%) in September 2021, largely due to vaccination. Anti-spike IgG seroprevalence was 99.6% (99.4-99.7%) among fully vaccinated individuals, 90.4% (88.8-91.7%) among unvaccinated with prior infection, and 11.5% (10.8-12.3%) among unvaccinated without known prior infection. Anti-spike IgG levels were reduced by 44.0% (34.9-51.7%) at 5-6 months compared to 0-3 months after infection. In fully vaccinated individuals, they decreased by 31.7% (29.4-33.9%) per month. In multivariable adjusted analyses, both seropositivity among unvaccinated and antibody levels among fully vaccinated individuals were higher at young age (<25 years), higher with a known prior infection, and lower in current smokers. Conclusion: Seroprevalence in Tyrol increased to 82.7% in September 2021, with the bulk of seropositivity stemming from vaccination. Antibody levels substantially and gradually declined after vaccination or infection.

scholarly journals Testing IgG antibodies against the RBD of SARS-CoV-2 is sufficient and necessary for COVID-19 diagnosis

PLoS ONE ◽  
2020 ◽  
Vol 15 (11) ◽  
pp. e0241164 ◽  
Author(s):  
Victoria Indenbaum ◽  
Ravit Koren ◽  
Shiri Katz-Likvornik ◽  
Mayan Yitzchaki ◽  
Osnat Halpern ◽  
...  
Keyword(s):  
Igg Antibodies ◽  
Serum Samples ◽  
Igg Antibody ◽  
Past Exposure ◽  
Iga Antibodies ◽  
Global Spread ◽  
Diagnostic Capacity ◽  
Antibody Levels ◽  
Antibody Kinetics ◽  
Kinetics Of

The COVID-19 pandemic and the fast global spread of the disease resulted in unprecedented decline in world trade and travel. A critical priority is, therefore, to quickly develop serological diagnostic capacity and identify individuals with past exposure to SARS-CoV-2. In this study serum samples obtained from 309 persons infected by SARS-CoV-2 and 324 of healthy, uninfected individuals as well as serum from 7 COVID-19 patients with 4–7 samples each ranging between 1–92 days post first positive PCR were tested by an “in house” ELISA which detects IgM, IgA and IgG antibodies against the receptor binding domain (RBD) of SARS-CoV-2. Sensitivity of 47%, 80% and 88% and specificity of 100%, 98% and 98% in detection of IgM, IgA and IgG antibodies, respectively, were observed. IgG antibody levels against the RBD were demonstrated to be up regulated between 1–7 days after COVID-19 detection, earlier than both IgM and IgA antibodies. Study of the antibody kinetics of seven COVID 19 patients revealed that while IgG levels are high and maintained for at least 3 months, IgM and IgA levels decline after a 35–50 days following infection. Altogether, these results highlight the usefulness of the RBD based ELISA, which is both easy and cheap to prepare, to identify COVID-19 patients even at the acute phase. Most importantly our results demonstrate that measuring IgG levels alone is both sufficient and necessary to diagnose past exposure to SARS-CoV-2.

scholarly journals IgM and IgA Antibody Responses in 12 Cases of Human Acquired Toxoplasmosis

1997 ◽  
Vol 39 (6) ◽  
pp. 327-332 ◽  
Author(s):  
Emília E. H. TAKAHASHI ◽  
Cláudio L. ROSSI
Keyword(s):  
Serological Test ◽  
Clinical Manifestations ◽  
Enzyme Linked Immunosorbent Assay ◽  
Serum Samples ◽  
Igm Antibodies ◽  
Iga Antibodies ◽  
Direct Elisa ◽  
Acute Toxoplasmosis ◽  
Antibody Levels ◽  
Acquired Toxoplasmosis

The persistence, in some subjects, of specific IgM antibodies to Toxoplasma gondii for several months after the acute phase of infection has complicated the interpretation of serological test results for toxoplasmosis. Several reports have emphasized the value of the detection of Toxoplasma-specific IgA antibodies for the diagnosis of acute toxoplasmosis. In this article, we report the follow-up profiles of Toxoplasma-specific IgM and IgA antibodies in serum samples obtained from 12 patients at various intervals after the onset of the clinical manifestations of infection. IgM antibodies were detected by the indirect immunofluorescence (IIF) test, antibody capture enzyme-linked immunosorbent assay (cELISA) and enzyme-mediated chemilluminescent technique (CmL). IgA antibodies were quantified by the direct ELISA (dELISA) and cELISA procedures. As defined by the manufacturer of the cELISA test for IgA used, most patients with acute toxoplasmosis have antibody levels > 40 arbritary units per ml (AU/ml). At values > 40 AU/ml, the cELISA for IgA detected significant antibody levels for a shorter time than the other techniques used for IgM and IgA detection. However, IgA levels <FONT FACE="Symbol">£</font> 40 AU/ml do not exclude the possibility of acute toxoplasmosis since such levels can be reached very soon after infection with T. gondii. The results obtained in the present study show that the serological diagnosis of acute toxoplasmosis may not be such an easy task. Our data suggest that use of the IgA-cELISA concomitantly with IgM antibody screening could permit, in some circumstances, a more efficient diagnosis of acute acquired toxoplasmosis

scholarly journals Ontogenesis of the formation of secretory antibodies to respiratory syncytial (RS) virus

1988 ◽  
Vol 101 (3) ◽  
pp. 565-575 ◽  
Author(s):  
N. P Leschinskaya ◽  
E. E Pokrovskaya ◽  
E. A Kantorovitch ◽  
S.K Grigorjeva ◽  
YA. S Shvartsman
Keyword(s):  
Old Age ◽  
Serum Antibody ◽  
Close Correlation ◽  
Secretory Iga ◽  
Igg Antibodies ◽  
Virus Infections ◽  
Neutralizing Activity ◽  
Iga Antibodies ◽  
Antibody Levels ◽  
Secretory Antibodies

SUMMARYExamination of sera from 184 children aged between 0 and 12 years and 161 adults revealed a close correlation between age and the level of humoral anti-RS virus immunity. Secretory IgG antibodies were found in children in their first months of life. Evidence for their release into secretions from the serum was obtained. This might explain the positive correlation between serum antibody levels in women recently confined with the morbidity due to RS virus in children during their first months of life. Secretory IgA antibodies were found from 4 months untill old age. The secretions of children and adults contained virus-neutralizing activity which was non-immunoglobulin in nature, as well as antibodies. However, in contrast to secretory antibody this material did not prevent development of severe RS virus infections.

Bordetella Pertussis Antibody Levels in DPT/Pentavalent Immunized Preschool Nigerian Children: A Cross-Sectional Study

2019 ◽  
Vol 15 (01) ◽  
pp. 011-015
Author(s):  
Glory Ekpo Bassey ◽  
Emmanuel Eyo Ekanem ◽  
Henry Chima Okpara ◽  
Komomo Ibor Eyong
Keyword(s):  
Pertussis Toxin ◽  
Bordetella Pertussis ◽  
Age Groups ◽  
Booster Vaccination ◽  
Rapid Decline ◽  
Age Group ◽  
Igg Antibodies ◽  
Cross Sectional ◽  
Nigerian Children ◽  
Antibody Levels

AbstractPertussis is a vaccine-preventable disease and antibodies formed are known to decline with time. The aim of this study was to measure Bordetella pertussis/toxin immunoglobulin G (IgG) antibodies in different age groups of Nigerian children and determine the age at which booster dose may be required. A total of 422 children, aged 6 to 60 months, were tested for the presence of B. pertussis/toxin IgG antibodies by ELISA (enzyme-linked immune sorbent assay). The highest positivity rate was in the 6 to 11 months of age group, while the highest negativity rate was in the age group of 24 to 35 months. We conclude that B. Pertussis/toxin IgG antibodies response is weak in Nigerian children after three doses of DPT (diphtheria, pertussis, and tetanus)/pentavalent vaccination, and there is a rapid decline of antibody levels between 12 and 35 months. We recommend that booster vaccination should be given at 12 to 15 months of age.

scholarly journals Two-Component Cluster Analysis of a Large Serodiagnostic Database for Specificity of Increases of IgG Antibodies against Pertussis Toxin in Paired Serum Samples and of Absolute Values in Single Serum Samples

2012 ◽  
Vol 19 (9) ◽  
pp. 1452-1456 ◽  
Author(s):  
Sabine C. de Greeff ◽  
Peter Teunis ◽  
Hester E. de Melker ◽  
Frits R. Mooi ◽  
Daan W. Notermans ◽  
...  
Keyword(s):  
Cluster Analysis ◽  
Pertussis Toxin ◽  
Area Under The Curve ◽  
Roc Curves ◽  
Enzyme Linked Immunosorbent Assay ◽  
Igg Antibodies ◽  
Serum Samples ◽  
Pertussis Infection ◽  
Diagnostic Laboratory ◽  
Two Component

ABSTRACTMeasuring IgG antibodies against pertussis toxin (IgG-Ptx) with an enzyme-linked immunosorbent assay (ELISA) can be used to diagnose pertussis infection; however, the cutoff points are not unanimously defined. To determine the diagnostic specificity of increases of IgG-Ptx in paired sera and of absolute values in single serum samples, we applied a two-component cluster analysis to serum samples of patients suspected for pertussis, whose sera had been submitted to a routine diagnostic laboratory between 2003 and 2009, and had been assayed with an in-house IgG-Ptx ELISA calibrated with the international FDA lot 3 IgG-Ptx reference serum. Children eligible for the acellular pertussis vaccination were excluded to avoid interference from a vaccine-induced IgG-Ptx rise. Binary distribution mixtures were fitted to the data. Receiver operating characteristic (ROC) curves were calculated for absolute values in single samples (n= 14,452) and increases in paired samples (n= 2,455). For both parameters, two subpopulations could be identified: a population with high reactivity (persons with pertussis infection) and a population with low reactivity (persons without pertussis infection). For absolute values in single samples, the area under the curve (AUC) of the ROC curve was 0.993 and the optimum cutoff (with the highest cumulative value of specificity plus sensitivity) was 67.7 IU/ml (95% confidence interval, 63.9 to 74.1; sensitivity, 96.4%; specificity, 95.7%). A previously determined diagnostic cutoff of 125 IU/ml was associated with a sensitivity of 88.1% and a specificity of 98.8%. For increases in paired sera, the AUC was 0.999 and the optimum cutoff was 3.1-fold (95% CI, 2.8 to 3.4; sensitivity, 99.6%; specificity, 99.2%). Given the methodology of this study, estimates of sensitivity probably are overrated (because pertussis patients without IgG-Ptx response are not detected), but estimates of specificities can be considered very accurate.

scholarly journals Low Hepatitis E Virus Prevalence Among Blood Donor in Dali in China

2020 ◽  
Author(s):  
Ping Fu ◽  
Baochai Lin ◽  
Bingting Wu ◽  
Ling Ke ◽  
Tianfu Yang ◽  
...  
Keyword(s):  
Blood Transfusion ◽  
Ethnic Minority ◽  
Odds Ratio ◽  
Hepatitis E Virus ◽  
Blood Donors ◽  
Hepatitis E ◽  
Enzyme Linked Immunosorbent Assay ◽  
Serum Samples ◽  
Iga Antibodies ◽  
Positive Rate

Abstract BACKGROUND: Hepatitis E virus (HEV) is a nonenveloped RNA virus causing Hepatitis E worldwide. An increasing transfusion transmission cases of HEV infections from asymptomatic blood donors which causing serious illnesses in immunosuppressed recipients have been reported in the past few years. China is one of the highly prevalent regions of HEV, it is important to evaluate the risk of HEV transmission from blood transfusion. METHODS: A total of 1864 serum samples from blood donors and demographic characteristics were randomly collected from Feb to Mar 2018 in Dali city. Anti-HEV IgG, IgM and IgA antibodies and HEV antigen were examined by enzyme-linked immunosorbent assay (ELISA). HEV RNA was detected by real-time PCR. Multivariable logistic regression modelling was used to examine risk factors associated with HEV prevalence.RESULTS: Overall, the positive rate of anti-HEV IgG, IgM, and IgA antibodies was 13.36% (249/1864), 1.13%(21/1864), and 1.82%(34/1864), respectively. However, none of the 1864 serum samples was detected as HEV antigen-positive nor HEV RNA positive. The positive rate of anti-HEV IgG antibody is high as 28.57% (2/7) in the donors with isolated elevated alanine aminotransferase (ALT). Females (16.69%) had a significantly higher HEV seroprevalence than males (13.04%) (odds ratio [OR]: 1.34 [95% CI, 1.02-1.75]). Other ethnic minority (24.32%) and Bai (18.85%) donors had a significantly higher HEV seroprevalence when compared to Han (12.21%) blood donors (odds ratio [OR], 2.25 [95% CI, 1.04-4.88] for other ethnic minority, 1.65 [95% CI, 1.24-2.19] for Bai). Conclusions: Dali, Yunnan province, China is an endemic region for HEV and have a relatively low risk of HEV transmission via blood transfusion. Whether to formulate the strategy for HEV screening in blood center needed further researched.

scholarly journals Serology characteristics of SARS-CoV-2 infection after exposure and post-symptom onset

2020 ◽  
Vol 56 (2) ◽  
pp. 2000763 ◽  
Author(s):  
Bin Lou ◽  
Ting-Dong Li ◽  
Shu-Fa Zheng ◽  
Ying-Ying Su ◽  
Zhi-Yong Li ◽  
...  
Keyword(s):  
Early Stage ◽  
Antibody Test ◽  
Igg Antibodies ◽  
Specific Diagnosis ◽  
Treatment And Prevention ◽  
Significant Difference ◽  
Antibody Levels ◽  
Antibody Dynamics ◽  
Serology Testing ◽  
Post Onset

BackgroundTimely diagnosis of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is a prerequisite for treatment and prevention. The serology characteristics and complement diagnosis value of the antibody test to RNA test need to be demonstrated.MethodSerial sera of 80 patients with PCR-confirmed coronavirus disease 2019 (COVID-19) were collected at the First Affiliated Hospital of Zhejiang University, Hangzhou, China. Total antibody (Ab), IgM and IgG antibodies against SARS-CoV-2 were detected, and the antibody dynamics during the infection were described.ResultsThe seroconversion rates for Ab, IgM and IgG were 98.8%, 93.8% and 93.8%, respectively. The first detectible serology marker was Ab, followed by IgM and IgG, with a median seroconversion time of 15, 18 and 20 days post exposure (d.p.e.) or 9, 10 and 12 days post onset (d.p.o.), respectively. The antibody levels increased rapidly beginning at 6 d.p.o. and were accompanied by a decline in viral load. For patients in the early stage of illness (0–7 d.p.o), Ab showed the highest sensitivity (64.1%) compared with IgM and IgG (33.3% for both; p<0.001). The sensitivities of Ab, IgM and IgG increased to 100%, 96.7% and 93.3%, respectively, 2 weeks later. When the same antibody type was detected, no significant difference was observed between enzyme-linked immunosorbent assays and other forms of immunoassays.ConclusionsA typical acute antibody response is induced during SARS-CoV-2 infection. Serology testing provides an important complement to RNA testing in the later stages of illness for pathogenic-specific diagnosis and helpful information to evaluate the adapted immunity status of patients.

scholarly journals Performance of a point of care test for detecting IgM and IgG antibodies against SARS-CoV-2 and seroprevalence in blood donors and health care workers in Panama

2020 ◽  
Author(s):  
Alcibiades Villarreal ◽  
Giselle Rangel ◽  
Xu Zhang ◽  
Digna Wong ◽  
Carolina De La Guardia ◽  
...  
Keyword(s):  
Health Care ◽  
Healthy Volunteer ◽  
Health Care Workers ◽  
Blood Donors ◽  
Lateral Flow ◽  
Lateral Flow Assay ◽  
Igg Antibodies ◽  
Serum Samples ◽  
Test Sensitivity ◽  
Care Workers

Novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the etiologic agent of the ongoing coronavirus disease 2019 (COVID-19) pandemic, which has reached 28 million cases worldwide in eight months. The serological detection of antibodies against the virus will play a pivotal role in complementing molecular tests to improve diagnostic accuracy, contact tracing, vaccine efficacy testing and seroprevalence surveillance. Here, we aimed first to evaluate a lateral flow assay ability to identify specific IgM and IgG antibodies against SARS-CoV-2 and second, to report the seroprevalence of these antibodies among health care workers and healthy volunteer blood donors in Panama. We recruited study participants between April 30th and July 7th, 2020. For the test validation and performance evaluation, we analyzed serum samples from participants with clinical symptoms and confirmed positive RT-PCR for SARS-CoV-2, and a set of pre-pandemic serum samples. We used two by two table analysis to determine the test sensitivity and specificity as well as the kappa agreement value with a 95% confidence interval. Then, we used the lateral flow assay to determine seroprevalence among serum samples from COVID-19 patients, potentially exposed health care workers, and healthy volunteer donors. Our results show this assay reached a positive percent agreement of 97.2% (95% CI 84.2-100.0%) for detecting both IgM and IgG. The assay showed a kappa of 0.898 (95%CI 0.811- 0.985) and 0.918 (95% CI 0.839-0.997) for IgM and IgG, respectively. The evaluation of serum samples from hospitalized COVID-19 patients indicates a correlation between test sensitivity and the number of days since symptom onset; the highest positive percent agreement (87% (95% CI 67.0-96.3%)) was observed at 15 days post-symptom onset. We found an overall antibody seroprevalence of 11.6% (95% CI 8.5-15.8%) among both health care workers and healthy blood donors. Our findings suggest this lateral flow assay could contribute significantly to implementing seroprevalence testing in locations with active community transmission of SARS-CoV-2.

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