COMPARISON OF RESULTS OBTAINED BY ELISA AND NEUTRALIZATION TEST IN ASSESSING THE PROTECTION OF POPULATION FROM TICK-BORNE ENCEPHALITIS

The enzyme-linked immunosorbent assay (ELISA) and the neutralization test (NT) are often used to determine the level of seropositive population and to evaluate the immunogenicity of vaccines. ELISA provides information on the total pool of antiviral antibodies, while NT allows the antiviral protection level of a person to be estimated. It is assumed that the 1:100 titer in ELISA and the 1:10 titer in NT are protective. Obviously, the ratio of the total pool and virus neutralizing antibodies can vary as a result of natural immunization or vaccination. In this study, two methods were used to study the blood serum samples taken in a group of inhabitants of the Sverdlovsk region aged from 1 to 60 years. The samples were collected before immunization and 30 days after two immunizations with inactivated vaccines against tick-borne encephalitis of different manufacturers. Immunizations were performed either according to a standard scheme (30-day interval between immunizations), or according to an emergency scheme (14-day interval). It was shown that the data on the presence of antiviral antibodies in protective titers obtained by ELISA and NT were consistent in more than 85% of cases. The discrepancies between the data are due, in the first place, to the difference in the sensitivities of the two methods. The proportion of seropositive people according to NT data is always greater than that according to the results of ELISA. Nevertheless, among 174 children, about 5% of recipients after a double immunization were seropositive according to ELISA, but did not have neutralizing antibodies in protective titers.

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Immunogenicity of a third dose viral-vectored COVID-19 vaccine after receiving two-dose inactivated vaccines in healthy adults

10.1101/2021.09.16.21263692 ◽

2021 ◽

Author(s):

Ritthideach Yorsaeng ◽

Nungruthai Suntronwong ◽

Harit Phowatthanasathian ◽

Suvichada Assawakosri ◽

Sitthichai Kanokudom ◽

...

Keyword(s):

Healthcare Workers ◽

Neutralization Test ◽

Enzyme Linked Immunosorbent Assay ◽

Receptor Binding Domain ◽

Wild Type ◽

Serum Samples ◽

Inactivated Vaccines ◽

Specific Igg ◽

June July ◽

High Immunogenicity

In June 2021, Thailand was hit by the delta variant of SARS-CoV-2 resulting in the biggest wave of COVID-19. Due to the widespread delta variant, more than 600 healthcare workers had COVID-19 despite completion of two-dose CoronaVac. The Ministry of Public Health recommended that healthcare workers received a third dose of AZD1222 to increase level of protection against SARS-CoV-2. However, immune response after the third vaccination with AZD1222 are limited. In this study, sera from those who received a booster of AZD1222 in June-July 2021 were tested for SARS-CoV-2 spike receptor-binding-domain (RBD) IgG, anti-RBD total immunoglobulins and anti-spike protein 1 (S1) IgA. The neutralizing activities in a subset of serum samples were tested against the wild type and variants of concern (B.1.1.7, B.1.617.2, and B.1.351) using an enzyme-linked immunosorbent assay-based surrogate virus neutralization test. Participants who received the booster of AZD1222 possessed higher levels of spike RBD-specific IgG, total immunoglobulins, and anti-S1 IgA than that two-dose vaccines (p < 0.001). They also elicited higher neutralizing activity against the wild type and all variants of concern than those in the recipients of the two-dose vaccines. This study demonstrated a high immunogenicity of the AZD1222 booster who completed the two-dose inactivated vaccines.

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TBE in Sweden

Tick-borne encephalitis - The Book ◽

10.33442/26613980_12b32-3 ◽

2020 ◽

Keyword(s):

Genetic Characterization ◽

Immunoglobulin M ◽

Enzyme Linked Immunosorbent Assay ◽

Second Phase ◽

Serum Samples ◽

Tick Borne Encephalitis ◽

Specific Immunoglobulin ◽

Tick Borne Encephalitis Virus ◽

First Time

Tick-borne encephalitis virus (TBEV) was isolated for the first time in Sweden in 1958 (from ticks and from 1 tick-borne encephalitis [TBE] patient).1 In 2003, Haglund and colleagues reported the isolation and antigenic and genetic characterization of 14 TBEV strains from Swedish patients (samples collected 1991–1994).2 The first serum sample, from which TBEV was isolated, was obtained 2–10 days after onset of disease and found to be negative for anti-TBEV immunoglobulin M (IgM) by enzyme-linked immunosorbent assay (ELISA), whereas TBEV-specific IgM (and TBEV-specific immunoglobulin G/cerebrospinal fluid [IgG/CSF] activity) was demonstrated in later serum samples taken during the second phase of the disease.

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Monoclonal Antibody-Based Antigen Capture Enzyme-Linked Immunosorbent Assay Reveals High Sensitivity of the Nucleocapsid Protein in Acute-Phase Sera of Severe Acute Respiratory Syndrome Patients

Clinical and Diagnostic Laboratory Immunology ◽

10.1128/cdli.12.1.135-140.2005 ◽

2005 ◽

Vol 12 (1) ◽

pp. 135-140 ◽

Cited By ~ 22

Author(s):

Biao Di ◽

Wei Hao ◽

Yang Gao ◽

Ming Wang ◽

Ya-di Wang ◽

...

Keyword(s):

Severe Acute Respiratory Syndrome ◽

Acute Phase ◽

Detection Rate ◽

Neutralization Test ◽

Protein Detection ◽

Enzyme Linked Immunosorbent Assay ◽

Serum Samples ◽

N Protein ◽

Antigen Capture ◽

Healthy Donors

ABSTRACT Accurate and timely diagnosis of severe acute respiratory syndrome coronavirus (SARS-CoV) infection is a critical step in preventing another global outbreak. In this study, 829 serum specimens were collected from 643 patients initially reported to be infected with SARS-CoV. The sera were tested for the N protein of SARS-CoV by using an antigen capture enzyme-linked immunosorbent assay (ELISA) based on monoclonal antibodies against the N protein of SARS-CoV and compared to 197 control serum samples from healthy donors and non-SARS febrile patients. The results of the N protein detection analysis were directly related to the serological analysis data. From 27 SARS patients who tested positive with the neutralization test, 100% of the 24 sera collected from 1 to 10 days after the onset of symptoms were positive for the N protein. N protein was not detected beyond day 11 in this group. The positive rates of N protein for sera collected at 1 to 5, 6 to 10, 11 to 15, and 16 to 20 days after the onset of symptoms for 414 samples from 298 serologically confirmed patients were 92.9, 69.8, 36.4, and 21.1%, respectively. For 294 sera from 248 serological test-negative patients, the rates were 25.6, 16.7, 9.3, and 0%, respectively. The N protein was not detected in 66 patients with cases of what was initially suspected to be SARS but serologically proven to be negative for SARS and in 197 serum samples from healthy donors and non-SARS febrile patients. The specificity of the assay was 100%. Furthermore, of 16 sera collected from four patients during the SARS recurrence in Guangzhou, 5 sera collected from 7 to 9 days after the onset of symptoms were positive for the N protein. N protein detection exhibited a high positive rate, 96 to 100%, between day 3 and day 5 after the onset of symptoms for 27 neutralization test-positive SARS patients and 298 serologically confirmed patients. The N protein detection rate continually decreased beginning with day 10, and N protein was not detected beyond day 19 after the onset of symptoms. In conclusion, an antigen capture ELISA reveals a high N protein detection rate in acute-phase sera of patients with SARS, which makes it useful for early diagnosis of SARS.

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Development of specific immunity in laboratory animals after co-immunization against seasonal influenza and COVID-19

Journal of microbiology epidemiology immunobiology ◽

10.36233/0372-9311-183 ◽

2022 ◽

Vol 98 (6) ◽

pp. 648-656

Author(s):

G. M. Ignatyev ◽

I. A. Leneva ◽

A. V. Atrasheuskaya ◽

L. I. Kozlovskaya ◽

N. P. Kartashova ◽

...

Keyword(s):

Neutralizing Antibodies ◽

Seasonal Influenza ◽

Neutralization Test ◽

Elisa Test ◽

Control Measures ◽

Laboratory Animals ◽

Enzyme Linked Immunosorbent Assay ◽

Post Vaccination ◽

Specific Immunity ◽

Influenza Prevention

Introduction. In clinical practice, the differential diagnosis of COVID-19 can be challenging during the flu season, entailing serious consequences such as delays in appropriate control measures against the SARS-CoV-2 pandemic. Another problem is posed by co-infection of SARS-CoV-2 and influenza virus (IV), which significantly contributes to the severity of the COVID-19 disease. This study was aimed to explore the cross-impact of co-administration of Russian influenza and COVID-19 vaccines on development of specific immunity in laboratory animals.Materials and methods. The study was conducted on BALB/c mice. The animals were inoculated intramuscularly with the vaccine for COVID-19 prevention (CoviVac) and the vaccine for influenza prevention (Flu-M). The sera from the immunized animals were examined separately. Three IV strains were used in the hemagglutination inhibition assay. Antibodies (Abs) against SARS-CoV-2 were detected by an enzyme-linked immunosorbent assay (ELISA). The neutralization test was performed to detect virus neutralizing antibodies against SARS-CoV-2 and IV.Results. Relatively high titers of specific Abs were found in the groups of animals inoculated with one vaccine and with two vaccines concurrently. In the groups of animals inoculated with CoviVac and with two vaccines concurrently, both in the ELISA test and in the neutralization test, the average titers of specific Abs against SARSCoV- 2 did not demonstrate any statistical difference. The group of animals inoculated concurrently with two vaccines demonstrated statistically higher titers of Abs against IV after the second immunization compared to the group of animals inoculated with Flu-M.Discussion. The study has shown that post-vaccination immunity both to IV and to SARS-CoV-2 develops after co-vaccination with two vaccines. The observed enhanced post-vaccination immune response to IV in the coimmunized laboratory animals needs further research.Conclusion. The performed studies suggest the possibility of co-administration of two vaccines to prevent influenza and COVID-19.

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Development of an Enzyme-Linked Immunosorbent Assay for Immunoglobulin M Antibodies against Measles Virus

Clinical and Diagnostic Laboratory Immunology ◽

10.1128/cdli.10.3.439-442.2003 ◽

2003 ◽

Vol 10 (3) ◽

pp. 439-442 ◽

Cited By ~ 3

Author(s):

F. Roodbari ◽

M. H. Roustai ◽

A. Mostafaie ◽

H. Soleimanjdahi ◽

R. Sarrami Foroshani ◽

...

Keyword(s):

Immunosorbent Assay ◽

Neutralizing Antibodies ◽

Measles Virus ◽

Clinical Symptoms ◽

Maculopapular Rash ◽

Immunoglobulin M ◽

Enzyme Linked Immunosorbent Assay ◽

Serum Samples ◽

Vaccination Programs ◽

Elisa System

ABSTRACT Measles is a highly contagious respiratory virus infection, with typical clinical symptoms including maculopapular rash, fever, cough, coryza, and conjunctivitis. Despite implementation of widespread vaccination programs throughout the world, the rates of global morbidity and mortality are still considerable. This study was performed to design a reliable indirect enzyme-linked immunosorbent assay (ELISA) to measure measles-specific immunoglobulin M (IgM). First, human IgM was purified, and then an anti-IgM antibody was produced in rabbits and purified in a multistep process. The rabbit IgG against human IgM was conjugated with peroxidase. Measles virus-infected Vero cells produced viral antigen. One hundred serum samples from infants of 9 to 18 months of age, mostly vaccinated, were evaluated for determining the presence of specific IgM antibodies against measles virus. The samples were also evaluated for neutralizing antibodies against measles virus by a microneutralization test (MNT). By comparing the results of the ELISA with those of MNT, it was demonstrated that ELISA had a sensitivity and specificity of 100 and 92%, respectively. On the other hand, when the results obtained by our ELISA system were compared with those of an imported measles virus IgM ELISA kit (EIAgen; Adaltis Italia SPa, Bologna, Italy), a high level of agreement was shown (k = 0.926).

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Evaluation of a Novel Reporter Virus Neutralization Test for Serological Diagnosis of Zika and Dengue Virus Infection

Journal of Clinical Microbiology ◽

10.1128/jcm.00975-17 ◽

2017 ◽

Vol 55 (10) ◽

pp. 3028-3036 ◽

Cited By ~ 21

Author(s):

Chao Shan ◽

Daniel A. Ortiz ◽

Yujiao Yang ◽

Susan J. Wong ◽

Laura D. Kramer ◽

...

Keyword(s):

Dengue Virus ◽

Neutralizing Antibodies ◽

Neutralization Test ◽

Reference Method ◽

Laboratory Diagnosis ◽

Virus Neutralization Test ◽

Virus Neutralization ◽

Enzyme Linked Immunosorbent Assay ◽

Reporter Virus ◽

Screening Assay

ABSTRACT Currently, the laboratory diagnosis of Zika virus (ZIKV) infection is primarily through the detection of ZIKV RNA or antibodies against ZIKV proteins. The detection of viral RNA is highly sensitive and specific, but periods of viremia and viruria are brief, limiting the utility of ZIKV RNA assays. Instead, most ZIKV infections are diagnosed serologically, using an IgM antibody capture enzyme-linked immunosorbent assay (MAC-ELISA) for screening, followed by a confirmatory plaque reduction neutralization test (PRNT). Typical turnaround times vary, due to assay incubation periods and a lack of clinical laboratories performing these tests. Recently, a novel luciferase-ZIKV- and -dengue virus (DENV)-based serological assay, which considerably improves the turnaround times and throughput for ZIKV diagnosis, was described. Using the traditional PRNT as a reference method, we evaluated the performance characteristics of the reporter virus neutralization test (RVNT) with 258 clinical serum specimens. The ZIKV RVNT produced primary ZIKV screening and secondary confirmation results in 4 days, with 100% reproducibility. As a screening assay, the ZIKV RVNT displayed excellent diagnostic accuracy, sensitivity, and specificity of 98.2%, 100%, and 98.1%, respectively. As a confirmatory assay, the ZIKV RVNT titers displayed 93.1% agreement with the traditional ZIKV PRNT titers. Overall, the RVNT accurately and reliably detects neutralizing antibodies in patient serum specimens, with improved turnaround times, and can be used for the serological detection of ZIKV infections. Due to the homogeneous 96-well format, the RVNT has also significantly improved the assay throughput to allow testing of a large number of specimens in a single run.

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Assessment of Mumps Virus-Specific Antibodies: Comparison of Plaque Reduction Neutralization Test and Enzyme-Linked Immunosorbent Assay Estimates

The Journal of Infectious Diseases ◽

10.1093/infdis/jiz345 ◽

2019 ◽

Vol 220 (9) ◽

pp. 1462-1468 ◽

Cited By ~ 3

Author(s):

Stéphanie Ravault ◽

Damien Friel ◽

Emmanuel Di Paolo ◽

Adrian Caplanusi ◽

Paul Gillard ◽

...

Keyword(s):

Antibody Response ◽

Immunosorbent Assay ◽

Neutralizing Antibodies ◽

Neutralization Test ◽

Pearson Correlation ◽

Mumps Virus ◽

Enzyme Linked Immunosorbent Assay ◽

Serological Response ◽

Moderate Correlation ◽

Plaque Reduction Neutralization Test

Abstract Background The plaque reduction neutralization test (PRNT), which measures a subset of immunoglobulin antibodies (functional neutralizing antibodies), and the enzyme-linked immunosorbent assay (ELISA), which measures total immunoglobulin (neutralizing and nonneutralizing antibodies), characterize different aspects of the anti–mumps virus antibody response after vaccination. Methods Data from a recent phase 3 clinical trial (NCT01681992) of 2 measles-mumps-rubella vaccines were used to compare anti-mumps antibody responses measured using an unenhanced PRNT (GSK; seropositivity cutoff and threshold, 2.5 and 4 times the 50% end-point dilution, respectively) with those estimated using an ELISA (thresholds, 5 and 10 ELISA units/mL, respectively). Results Of 3990 initially seronegative samples, 3284 (82.3%) were seropositive after vaccination for anti-mumps antibodies in both assays. The Pearson correlation coefficient for double-positive samples was 0.57, indicative of a moderate correlation. Receiver operating characteristic curve analysis showed that an ELISA threshold of 51.7 ELISA units/mL best corresponded to the PRNT seroresponse threshold. There was no obvious vaccine brand effect on the correlation between assays. Conclusions The moderate correlation between the anti-mumps antibody measurements obtained with PRNT and ELISA reflects different aspects of the serological response. In the absence of a well-defined protective serological threshold, PRNT provides complementary information on the antibody response, whereas ELISA remains a critically useful measurement of vaccine immunogenicity.

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Comparison of the Serum Neutralization Test and a Competitive Enzyme-Linked Immunosorbent Assay for the Detection of Antibodies to Vesicular Stomatitis Virus New Jersey and Vesicular Stomatitis Virus Indiana

Journal of Veterinary Diagnostic Investigation ◽

10.1177/104063870201400309 ◽

2002 ◽

Vol 14 (3) ◽

pp. 240-242 ◽

Cited By ~ 8

Author(s):

Juan Francisco Alvarado ◽

Gaby Dolz ◽

Marco V. Herrero ◽

Brian McCluskey ◽

Mo Salman

Keyword(s):

New Jersey ◽

Confidence Interval ◽

Vesicular Stomatitis Virus ◽

Immunosorbent Assay ◽

Neutralization Test ◽

Enzyme Linked Immunosorbent Assay ◽

Serum Samples ◽

Serum Neutralization ◽

Serum Neutralization Test ◽

Vesicular Stomatitis

A competitive enzyme-linked immunosorbent assay (C-ELISA) for the detection of antibodies against vesicular stomatitis virus New Jersey (VSV-NJ) and vesicular stomatitis virus Indiana (VSV-IN) was compared with the serum neutralization test (SNT) using 1,106 serum samples obtained from dairy cattle on sentinel study farms in the Poás region of Costa Rica. Kappa coefficients between the C-ELISA and the SNT were 0.8871 (95% confidence interval [CI]: 0.8587–0.9155) and 0.6912 (95% CI: 0.6246–0.7577) for the VSV-NJ and VSV-IN tests, respectively. These results indicate good to excellent agreement between the 2 tests under these conditions.

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Monoclonal antibody-based capture ELISA in the diagnosis of previous dengue infection

Virology Journal ◽

10.1186/s12985-019-1222-9 ◽

2019 ◽

Vol 16 (1) ◽

Cited By ~ 2

Author(s):

Chukiat Sirivichayakul ◽

Kriengsak Limkittikul ◽

Pornthep Chanthavanich ◽

Sutee Yoksan ◽

Anuttarasakdi Ratchatatat ◽

...

Keyword(s):

Monoclonal Antibody ◽

Neutralization Test ◽

Dengue Infection ◽

Severe Dengue ◽

Enzyme Linked Immunosorbent Assay ◽

Dengue Vaccine ◽

Serum Samples ◽

Specific Immunoglobulin ◽

Study Population ◽

Dengue Prevention

Abstract Background Dengue is an important mosquito-borne disease. There is currently only one licensed vaccine for dengue prevention. The vaccine provides higher efficacy in pre-vaccination dengue-seropositive persons but a higher risk of subsequent more severe dengue in dengue-seronegative persons. It is recommended that the dengue vaccine may be given in dengue-seropositive individuals or as mass vaccination without individual pre-vaccination screening in areas where the dengue seroprevalence is > 80% in children aged 9 years. We evaluated a dengue specific immunoglobulin G monoclonal antibody-based capture enzyme-linked immunosorbent assay (MAb-ELISA) in the diagnosis of previous dengue infection using serum samples from the cohort study in Ratchaburi Province, Thailand. Methods The MAb-ELISA was compared to 70% plaque reduction neutralization test (PRNT70) in 453 serum samples from children aged 3–11 years in Ratchaburi Province, Thailand. Results The sensitivity and specificity of MAb-ELISA at the positive to negative (P/N) ratio cut-off level of > 3 were both 0.91 in the diagnosis of previous dengue infection, compared to PRNT70. The false positivity was mainly in Japanese encephalitis (JE) seropositive subjects. Conclusions This research provides evidence that MAb-ELISA is useful for dengue seroprevalence study and dengue pre-vaccination screening. JE seropositivity was the major cause of false positive result in the study population.

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CORRELATION BETWEEN ENROVIRUS INFECTION AND ACUTE STROKE ON THE GROUND OF VIROLOGICAL, MOLECULAR GENETIC AND SEROLOGICAL METHODS OF DIAGNOSIS

Medical Science of Ukraine (MSU) ◽

10.32345/2664-4738.3-4.2017.06 ◽

2018 ◽

Vol 13 (3-4) ◽

pp. 38-45

Author(s):

N.G. Andriushkova ◽

N.S. Turchina ◽

V.V. Melnуk ◽

L.V. Dolinchuk ◽

V.A. Poniatovskyi ◽

...

Keyword(s):

Blood Serum ◽

Acute Stroke ◽

Main Group ◽

Trigger Factor ◽

Vascular Pathology ◽

Enzyme Linked Immunosorbent Assay ◽

Enterovirus Infection ◽

Serum Samples ◽

Isolation And Identification ◽

Ig G

Relevance. Numerous virological studies prove the importance of enteroviruses in human somatic pathology. However, the etiopathogenetic role of enterovirus infection in patients with acute cerebrovascular disorder (GVMK) is not sufficiently highlighted. Objective: to establish the value of enterovirus infection as a trigger factor in the pathogenesis of acute stroke. Materials and methods. The pear blood serum of 72 patients with acute stroke (main group) and 35 patients with neurological pathology without vascular pathology (group of comparison) were screened for presence of enteroviruses using the virological method, detection of enterovirus genomes using a polymerase chain reaction and the presence of specific Ig M and Ig G to enteroviruses in the enzyme-linked immunosorbent assay (ELISA). Results. The enterovirus genomes were isolated from blood serum in 23,6±5,9 % of patients with acute stroke, that is significantly higher than in patients of the comparison group – 2,9±2,8 % (p <0,05). The enteroviruses were isolated in 11 cases of 17 PCR-positive blood serum samples of the main group. These viruses were identified as Coxsackie B viruses (serotypes 2, 3, 4) and ECHO viruses (serotypes 6, 9, 27 (two strains), 29), three strains of viruses could not be identified. The presence of specific Ig M and Ig G in blood serum of 4 patients with HPMC, as well as enterovirus genomes, has been established. It suggest that they have a recent enterovirus infection, or can indicate a recent enterovirus infection or exacerbation of chronic enterovirus infection. Only specific Ig G in the absence of Ig M were detected in blood serum of 4 PCR positive patients, that can indicate chronic enterovirus infection. Only Ig M in the absence of Ig G was detected in blood serum of 6 PCR-positive patients, that can indicate acute enterovirus infection. No Ig M or Ig G in serum from three PCR-positive patients were detected, possibly due to the presence of latent enterovirus infection. Conclusions. Acute and chronic persistent enterovirus infection plays a possible trigger role in the development of acute stroke. The combination of PCR to detect genomes of enteroviruses, virological for the isolation and identification of viruses, and ELISA for the detection of specific Ig M and Ig G to enteroviruses should be recommended for the diagnosis of persistent enterovirus infection in patients with acute stroke.

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