Objective: To evaluate the immunogenicity of inactivated quadrivalent influenza vaccine (QIV) in adults aged 18-64 years, through a Meta-analysis. Methods: Literature was retrieved by searching the Medline, Cochrane Library, Science Direct in the past decade. All the studies were under random control trial (RCT) and including data related to immunogenicity which involving sero-protection rate (SPR) and sero-conversion rate (SCR) of the QIV, versus inactivated trivalent influenza vaccine (TIV) in the population aged 18 to 64. Revman 5.3 software was employed to manipulate the pooled date of the included literature. Result: A total of 8 studies for the SPR and SCR of the shared strains (two A lineage and one B lineage) were included. There appeared no significant differences in the response rates between the two vaccines. As for QIV versus TIV (B/Yamagata), the pooled RR of the SPR for B/Victoria was 1.28 (95%CI: 1.08-1.51, P<0.05), with the pooled RR of the SCR for B/Victoria as 1.94 (95%CI: 1.50-2.50, P<0.05). For QIV versus TIV (B/Victoria), the pooled RR of the SPR for B/Yamagata as 1.10 (95%CI: 1.02-1.18, P<0.05), and the pooled RR of SCR for B/Yamagata as 1.99 (95%CI: 1.34-2.97, P<0.05). Conclusion: In the population aged 18-64 years, inactivated QIV was equivalently immunogenic against the shared three strains included in the activated TIV while a superior immunogenic effect was noticed in the vaccine strain which did not include the inactivated QIV.
Adolescent ; Adult ; Antibodies, Viral/blood* ; Drug-Related Side Effects and Adverse Reactions ; Hemagglutination Inhibition Tests ; Humans ; Influenza A virus/immunology* ; Influenza B virus/immunology* ; Influenza Vaccines/immunology* ; Influenza, Human/prevention & control* ; Middle Aged ; Vaccines, Inactivated/immunology* ; Young Adult

BACKGROUND: In March 2013, human infection with avian influenza A (H7N9) virus emerged in China, causing serious public health concerns and raising the possibility of avian-source pandemic influenza. Thus, the development of an effective vaccine for preventing and rapidly controlling avian influenza A (H7N9) virus is needed. In this study, we evaluated the immunogenicity of a synthetic DNA vaccine against H7 HA antigens in mice. MATERIALS AND METHODS: The synthetic consensus H7 HA DNA vaccine (25 or 50 µg) was administered to BALB/c mice at 0, 14, and 28 days by intramuscular injection followed by electroporation. Humoral and cellular immune responses were analyzed in a hemagglutination inhibition test and interferon-gamma enzyme-linked immunospot (ELISpot) assay, respectively. RESULTS: H7 HA-vaccinated mice showed 100% seroprotection and seroconversion rate against H7N9 reassortant influenza virus after both second and third immunizations. The geometric mean titer by the hemagglutination inhibition test increased with an increasing number of immunizations. However, there was no significant difference in geometric titer between the two groups injected with 25 and 50 µg of H7 HA DNA vaccine after two (79.98 vs. 107.65, P = 0.39) and three (159.96 vs. 215.28, P = 0.18) doses. In addition, the ELISpot assay revealed that administration of H7 HA DNA vaccine induced potent interferon-gamma production from mouse splenocytes. CONCLUSIONS: This study demonstrated the humoral and cellular immunogenicity of synthetic consensus H7 HA DNA vaccine in mice. This work demonstrates the potential of the H7 HA DNA vaccine as an efficient tool for the rapid control of emerging influenza A (H7N9) virus.
Animals ; China ; Consensus ; DNA* ; Electroporation ; Enzyme-Linked Immunospot Assay ; Hemagglutination Inhibition Tests ; Humans ; Immunity, Cellular ; Immunization ; Influenza in Birds* ; Influenza, Human ; Injections, Intramuscular ; Interferon-gamma ; Mice* ; Orthomyxoviridae ; Pandemics ; Public Health ; Seroconversion

The virus neutralization (VN) test was used to determine potency of the infectious bronchitis (IB) vaccine. The results of VN, hemagglutination inhibition (HI), and enzyme-linked immunosorbent assay (ELISA) were compared with those of the IBV M41. The r² values between VN and HI titers and the ELISA antibody titer were 0.8782 and 0.0336, respectively, indicating a high correlation between VN and HI, but not VN and ELISA. The Cohen's kappa coefficient between the VN titer of 2 log₁₀ and HI titer of 5 log₂ was 0.909. Our results showed that VN could be replaced with HI for testing the potency of IBV M41.
Bronchitis ; Enzyme-Linked Immunosorbent Assay* ; Hemagglutination Inhibition Tests* ; Hemagglutination* ; Infectious bronchitis virus* ; Neutralization Tests* ; Vaccine Potency*

Preparation of maternal strain A/PR/8/34 HA antiserum for influenza virus classical reassortment. A/PR/8/34 virus was digested by bromelain after inactivation and purification. 5%-20% sucrose continuous density gradient centrifugation method was used to purify HA protein. SIRD method was used to select the target protein. SDS-PAGE method was used to identified HA protein. High Immunogenic A/PR/8/34 HA protein was successfully prepared and HI titer reached 10240. High purity HA antiserum was identified by SIRD method. The key reagent in the classical reassortment of influenza virus was prepared, and the complete set of technical methods were explored, which laid the foundation for the independent research and development of seasonal influenza vaccine strains of China.
Animals ; Antibodies, Viral ; immunology ; Electrophoresis, Polyacrylamide Gel ; Female ; Hemagglutination Inhibition Tests ; Hemagglutinin Glycoproteins, Influenza Virus ; analysis ; immunology ; Humans ; Influenza A Virus, H1N1 Subtype ; genetics ; immunology ; Influenza, Human ; immunology ; virology ; Rabbits ; Reassortant Viruses ; genetics ; immunology

BACKGROUND: Dengue is a major health problem. The lack of data on the usefulness of rapid diagnostic tests for early detection of dengue has generated interest in determining their validity.

OBJECTIVES: This research aimed to determine the validity of dengue IgA antibody versus NS1 antigen test as rapid diagnostic tests for early detection of dengue using Hemagglutination Inhibition test (HI) as standard reference.

METHODOLOGY: This study included 51 pediatric patients being evaluated for dengue in a private hospital from March 01, 2012 to October 30, 2012. Paired serum samples from patients suspected of dengue and had fever of not more than seven days were examined. Initial blood samples were collected on the first day of consult and tested for dengue IgA antibody, dengue NS1 antigen, and dengue HI tests. Second blood samples for HI were collected seven days after the initial extraction

RESULTS: The 51 serum samples used in this study came from 29 males and 22 females. From these samples, sensitivity of dengue IgA antibody was 80% with 95% CI (70-90) while specificity was at 50% with 95% CI(34-64) while dengue NS1 antigen which showed sensitivity of 27% with 95% CI (15-39) and specificity of 67% with 95% CI (54-86). IgA rapid test demonstrated 71% positivity in detecting acute primary dengue infection and 82% for acute secondary infection. NS1 detected 43% of primary infection and 24% of secondary infection.

CONCLUSION: Dengue IgA antibody rapid test was more sensitive than NS1 antigen test for early diagnosis of dengue and had better performance in detecting primary and secondary dengue.

Human ; Male ; Female ; Adolescent ; Child ; Child Preschool ; Dengue-diagnosis, Diagnostic Techniques and Procedures ; Immunoglobulin A ; Antigens ; Hemagglutination Inhibition Tests

PURPOSE: Although influenza is regarded as a major cause of morbidity and mortality in immunocompromised patients, vaccine coverage remains poor. We evaluated the immunogenicity of influenza vaccines in colorectal cancer patients. MATERIALS AND METHODS: In this study, 40 colorectal cancer patients who received an influenza vaccine at the Korea Cancer Center Hospital during the 2009-2010 and 2010-2011 influenza seasons were analyzed. The blood samples were collected at prevaccination and 30 days post vaccination, and antibody titers were measured using the hemagglutination-inhibition tests. RESULTS: In the 2009-2011 season, the seroprotection rate for H1N1 (94.7%) was significantly higher than that for H3N2 (42.1%) and B (47.3%). The seroconversion rate was 52.6%, 26.3%, and 36.8% for H1N1, H3N2, and B, respectively. Fold increase of geometric mean titer (MFI) was 3.86, 1.49, and 3.33 for H1N1, H3N2, and B, respectively. In the 2010-2011 season, the seroprotection rate for H1N1 (57.1%) was significantly higher than that for H3N2 (52.4%) and B (38.1%). The seroconversion rate was 52.4%, 47.6% and 33.3% for H1N1, H3N2, and B, respectively. MFI was 12.29, 3.62 and 4.27 for H1N1, H3N2, and B, respectively. CONCLUSION: Our study cohort showed an acceptable immune response to an influenza vaccine without significant adverse effects, supporting the recommendation for annual influenza vaccination in colorectal cancer patients.
Cohort Studies ; Colorectal Neoplasms* ; Hemagglutination Inhibition Tests ; Humans ; Immunocompromised Host ; Influenza Vaccines* ; Influenza, Human* ; Korea ; Mortality ; Seasons ; Vaccination

A recombinant hemagglutinin-neuraminidase (rHN) protein from Newcastle disease virus (NDV) with hemagglutination (HA) activity was expressed in Spodoptera frugiperda cells using a baculovirus expression system. The rHN protein extracted from infected cells was used as an antigen in a hemagglutination inhibition (HI) test for the detection and titration of NDV-specific antibodies present in chicken sera. The rHN antigen produced high HA titers of 2(13) per 25 microL, which were similar to those of the NDV antigen produced using chicken eggs, and it remained stable without significant loss of the HA activity for at least 12 weeks at 4degrees C. The rHN-based HI assay specifically detected NDV antibodies, but not the sera of other avian pathogens, with a specificity and sensitivity of 100% and 98.0%, respectively, in known positive and negative chicken sera (n = 430). Compared with an NDV-based HI assay, the rHN-based HI assay had a relative sensitivity and specificity of 96.1% and 95.5%, respectively, when applied to field chicken sera. The HI titers of the rHN-based HI assay were highly correlated with those in an NDV-based HI assay (r = 0.927). Overall, these results indicate that rHN protein provides a useful alternative to NDV antigen in HI assays.
Animals ; Antibodies, Viral/*blood ; Antigens, Viral/*diagnostic use/genetics/metabolism ; Baculoviridae/genetics ; Chickens ; HN Protein/*diagnostic use/genetics/metabolism ; Hemagglutination Inhibition Tests/*methods/veterinary ; Newcastle Disease/*diagnosis/immunology/virology ; Newcastle disease virus/genetics/*immunology/metabolism ; Poultry Diseases/*diagnosis/immunology/virology ; Recombinant Proteins/diagnostic use/genetics/metabolism ; Sf9 Cells ; Spodoptera

We aimed to compare the immune response induced by natural infection with 2009 pandemic influenza A/H1N1 (pH1N1) virus and by monovalent pH1N1 vaccination in children and adolescents. This cross-sectional clinical study was conducted at 3 hospitals in Korea from February to May 2010. A total of 266 healthy subjects aged from 6 months to 18 yr were tested for the presence of the antibody against pH1N1 using hemagglutination inhibition (HI) test. Information about pH1N1 vaccination and laboratory-confirmed pH1N1 infection history was obtained. The overall rate of HI titers of > or = 1:40 against pH1N1 was 38.7%, and the geometric mean titer (GMT) was 20.5. Immunogenicity of pH1N1 vaccination only was reflected by a 41.1% of seroprotection rate and a GMT of 22.5. Immunogenicity of natural infection only was reflected by a 61.0% of seroprotection rate and a GMT of 40.0. GMT was significantly higher in the subjects of natural infection group than in the subjects of pH1N1 vaccination group (P < 0.001). The immune responses induced by natural pH1N1 infection exceed those induced by pH1N1 vaccinations.
Adolescent ; Antibodies, Neutralizing/blood ; Antibody Formation ; Child ; Child, Preschool ; Cross-Sectional Studies ; Hemagglutination Inhibition Tests ; Humans ; Infant ; Influenza A Virus, H1N1 Subtype/*immunology/metabolism ; Influenza, Human/epidemiology/*immunology/prevention & control ; Pandemics ; Vaccination

BACKGROUND: Validation of hemagglutination inhibition (HI) assays is important for evaluating antibody responses to influenza virus, and selection of erythrocytes for use in these assays is important. This study aimed to determine the correlation between receptor binding specificity and effectiveness of the HI assay for detecting antibody response to pandemic influenza H1N1 (pH1N1) virus. METHODS: Hemagglutination (HA) tests were performed using erythrocytes from 6 species. Subsequently, 8 hemagglutinating units of pH1N1 from each species were titrated by real-time reverse transcription-PCR. To investigate the effect of erythrocyte binding preference on HI antibody titers, comparisons of HI with microneutralization (MN) assays were performed. RESULTS: Goose erythrocytes showed most specific binding with pH1N1, while HA titers using human erythrocytes were comparable to those using turkey erythrocytes. The erythrocyte binding efficiency was shown to have an impact on antibody detection. Comparing MN titers, HI titers using turkey erythrocytes yielded the most accurate results, while those using goose erythrocytes produced the highest geometric mean titer. Human blood group O erythrocytes lacking a specific antibody yielded results most comparable to those obtained using turkey erythrocytes. Further, pre-existing antibody to pH1N1 and different erythrocyte species can distort HI assay results. CONCLUSIONS: HI assay, using turkey and human erythrocytes, yielded the most comparable and applicable results for pH1N1 than those by MN assay, and using goose erythrocytes may lead to overestimated titers. Selection of appropriate erythrocyte species for HI assay allows construction of a more reliable database, which is essential for further investigations and control of virus epidemics.
Adult ; Animals ; Antibodies, Neutralizing/immunology ; Antibodies, Viral/*analysis/immunology ; Chickens ; Erythrocytes/*metabolism ; Female ; Geese ; *Hemagglutination Inhibition Tests ; Horses ; Humans ; Influenza A Virus, H1N1 Subtype/genetics/immunology/*metabolism ; Influenza, Human/epidemiology/immunology/virology ; Male ; Middle Aged ; Neutralization Tests ; Pandemics ; Swine ; Turkeys

PURPOSE: For evaluating the immunogenicity of an influenza vaccine, the microneutralization (MN) test has a higher sensitivity and specificity as compared to the hemagglutination inhibition (HI) test. However, the MN test is more time consuming and is difficult to standardize. We performed the MN test to determine its usefulness as an alternative or complementary test to the HI test for evaluating the immunogenicity of influenza vaccines. METHODS: We compared the MN test with the HI test using 50 paired samples taken from a previous clinical study (2008-2009) in Korean children under 18 years of age. RESULTS: The linear correlation coefficients of the 2 tests for H3N2, H1N1, and influenza B were 0.69, 0.70, and 0.66, respectively. We identified a high index of coincidence between the 2 tests. For an influenza vaccine, the postvaccination seroprotection rates and seroconversion rates determined by the MN test were 78.0% and 96.0%, 90% and 42.0%, and 42.0% and 48.0% for H3N2, H1N1, and influenza B, respectively. Geometric mean titer fold increases of H3N2, H1N1, and influenza B were 2.89, 5.04, and 4.29, respectively, and were 2.5-fold higher. We obtained good results in the evaluation of the immunogenicity of the 2008-2009 seasonal influenza vaccines. CONCLUSION: We found that the MN test was as effective as the HI test. Therefore, we suggest that the MN test can be used as an alternative or complementary test to the HI test for evaluating the immunogenicity of influenza vaccines.
Child ; Hemagglutination ; Hemagglutination Inhibition Tests ; Humans ; Influenza Vaccines ; Influenza, Human ; Neutralization Tests ; Seasons ; Sensitivity and Specificity