Measuring Influenza Neuraminidase Inhibition Antibody Titers by Enzyme-linked Lectin Assay

Propolis was widely used in health preservation and disease healing, it contains many ingredients. The previous study had been revealed that the propolis has a wide range of efficacy, such as antiviral, immune enhancement, anti-inflammatory and so on, but its antiviral components and underlying mechanism of action remain unknown. In this study, we investigated the chemical composition, and anti-PPV and immunological enhancement of Propolis Flavonoid(PF). Chemical composition of PF was distinguished by UPLC-Q/TOF-MS/MS analysis.The presence and characterized of 26 major components was distinguished in negative ionization modes.To evaluate the effects of PF used as adjuvant on the immune response porcine parvovirus (PPV). Thirty Landrace-Yorkshire hybrid sows were randomly assigned to 3 groups, and the sows in adjuvant groups were intramuscular injected PPV vaccine with 2.0 mL PF adjuvant (PA), oilemulsion adjuvant (OA), respectively. After that, serum hemagglutination inhibition antibody titers, IgM and IgG subclasses, eripheral lymphocyte proliferation activity, and concentrations of cytokines were measured. Results indicated an enhancing effect of PA on IgM, IL-2, IL-4, IFN-γ and the IgG subclass responses. These findings suggested that PA could significantly enhance the immune responses. Furthermore, we screened the chemical components the effective of anti-PPV, Ferulic acid have an excellently anti-PPV effective.

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Hemagglutination Inhibition Antibody Titers as a Correlate of Protection for Inactivated Influenza Vaccines in Children

The Pediatric Infectious Disease Journal ◽

10.1097/inf.0b013e3182367662 ◽

2011 ◽

Vol 30 (12) ◽

pp. 1081-1085 ◽

Cited By ~ 209

Author(s):

Steven Black ◽

Uwe Nicolay ◽

Timo Vesikari ◽

Markus Knuf ◽

Giuseppe Del Giudice ◽

...

Keyword(s):

Hemagglutination Inhibition ◽

Influenza Vaccines ◽

Correlate Of Protection ◽

Inhibition Antibody ◽

Antibody Titers

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Impact of Immune Priming, Vaccination, and Infection on Influenza A(H3N2) Antibody Landscapes in Children

The Journal of Infectious Diseases ◽

10.1093/infdis/jiaa665 ◽

2020 ◽

Author(s):

Michael Hinojosa ◽

Samuel S Shepard ◽

Jessie R Chung ◽

Jennifer P King ◽

Huong Q McLean ◽

...

Keyword(s):

Influenza A ◽

Antibody Responses ◽

Influenza Vaccines ◽

Infection Status ◽

Immune Priming ◽

Age Related ◽

Vaccine Antigens ◽

Inhibition Antibody ◽

Antibody Titers ◽

Virus Influenza

Abstract Background Preexisting antibodies to influenza, shaped by early infection and subsequent exposures, may impact responses to influenza vaccination. Methods We enrolled 72 children (aged 7–17 years) in 2015–2016; all received inactivated influenza vaccines. Forty-one were also vaccinated in 2014–2015, with 12 becoming infected with A(H3N2) in 2014–2015. Thirty-one children did not have documented influenza exposures in the prior 5 seasons. Sera were collected pre- and postvaccination in both seasons. We constructed antibody landscapes using hemagglutination inhibition antibody titers against 16 A(H3N2) viruses representative of major antigenic clusters that circulated between 1968 and 2015. Results The breadth of the antibody landscapes increased with age. Vaccine-induced antibody responses correlated with boosting of titers to previously encountered antigens. Postvaccination titers were the highest against vaccine antigens rather than the historic A(H3N2) viruses previously encountered. Prevaccination titers to the vaccine were the strongest predictors of postvaccination titers. Responses to vaccine antigens did not differ by likely priming virus. Influenza A(H3N2)-infected children in 2014–2015 had narrower antibody landscapes than those uninfected, but prior season infection status had little effect on antibody landscapes following 2015–2016 vaccination. Conclusions A(H3N2) antibody landscapes in children were largely determined by age-related immune priming, rather than recent vaccination or infection.

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Hemagglutination Inhibition Antibody Titers as a Correlate of Protection Against Seasonal A/H3N2 Influenza Disease

Open Forum Infectious Diseases ◽

10.1093/ofid/ofv067 ◽

2015 ◽

Vol 2 (2) ◽

Cited By ~ 22

Author(s):

Anne Benoit ◽

Jiri Beran ◽

Jeanne-Marie Devaster ◽

Meral Esen ◽

Odile Launay ◽

...

Keyword(s):

Characteristic Curve ◽

Fold Increase ◽

Correlate Of Protection ◽

Pooled Data ◽

Trivalent Influenza Vaccine ◽

Inhibition Antibody ◽

Antibody Titers ◽

H3n2 Influenza ◽

Antibody Levels ◽

The Relationship

Background. To investigate the relationship between hemagglutinin-inhibition (HI) antibody levels to the risk of influenza disease, we conducted a correlate of protection analysis using pooled data from previously published randomized trials. Methods. Data on the occurrence of laboratory-confirmed influenza and HI levels pre- and postvaccination were analyzed from 4 datasets: 3 datasets included subjects aged <65 years who received inactivated trivalent influenza vaccine (TIV) or placebo, and 1 dataset included subjects aged ≥65 years who received AS03-adjuvanted TIV (AS03-TIV) or TIV. A logistic model was used to evaluate the relationship between the postvaccination titer of A/H3N2 HI antibodies and occurrence of A/H3N2 disease. We then built a receiver-operating characteristic curve to ide.jpegy a potential cutoff titer between protection and no protection. Results. The baseline odds ratio of A/H3N2 disease was higher for subjects aged ≥65 years than <65 years and higher in seasons of strong epidemic intensity than moderate or low intensity. Including age and epidemic intensity as covariates, a 4-fold increase in titer was associated with a 2-fold decrease in the risk of A/H3N2 disease. Conclusions. The modeling exercise confirmed a relationship between A/H3N2 disease and HI responses, but it did not allow an evaluation of the predictive power of the HI response.

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Autistic children exhibit undetectable hemagglutination-inhibition antibody titers despite previous rubella vaccination

Journal of Autism and Childhood Schizophrenia ◽

10.1007/bf01543467 ◽

1976 ◽

Vol 6 (3) ◽

pp. 269-274 ◽

Cited By ~ 69

Author(s):

E. Gene Stubbs

Keyword(s):

Hemagglutination Inhibition ◽

Autistic Children ◽

Inhibition Antibody ◽

Antibody Titers ◽

Rubella Vaccination

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Association between hemagglutination inhibition antibody titers and protection against RT-PCR confirmed influenza illness in children 6−35 months of age: statistical evaluation of a correlate of protection

Open Forum Infectious Diseases ◽

10.1093/ofid/ofab477 ◽

2021 ◽

Author(s):

Jasur Danier ◽

Andrea Callegaro ◽

Jyoti Soni ◽

Alfoso Carmona ◽

Pope Kosalaraska ◽

...

Keyword(s):

Antibody Titer ◽

Hemagglutination Inhibition ◽

H1n1 Influenza ◽

Rt Pcr ◽

Individual Level ◽

Correlate Of Protection ◽

Inhibition Antibody ◽

Clinical Protection ◽

Antibody Titers ◽

H3n2 Influenza

Abstract Background Data from a randomized, controlled efficacy trial of an inactivated quadrivalent influenza vaccine in children 6−35 months of age were used to determine whether hemagglutination inhibition (HI) antibody titer against A/H1N1 and A/H3N2 is a statistical correlate of protection (CoP) for the risk of RT-PCR-confirmed influenza associated with the corresponding strain. Methods The Prentice criteria were used to statistically validate strain-specific HI antibody titer as a CoP. The probability of protection was identified using Dunning's model corresponding to a pre-specified probability of protection at an individual level. The group level protective threshold was identified using Siber's approach, leading to unbiased predicted vaccine efficacy (VE). A case-cohort sub-sample was used for this exploratory analysis. Results Prentice criteria confirmed that HI titer is a statistical CoP for RT-PCR-confirmed influenza. Dunning's model predicted a probability of protection of 49.7% against A/H1N1 influenza and 54.7% against A/H3N2 influenza at an HI antibody titer of 1:40 for the corresponding strain. Higher titers of 1:320 were associated with more than 80% probability of protection. Siber's method predicted VE of 61.0% at a threshold of 1:80 for A/H1N1 and 46.6% at 1:113 for A/H3N2. Conclusions The study validated HI antibody titer as a statistical CoP, by demonstrating that HI titer is correlated with clinical protection against RT-PCR-confirmed influenza associated with the corresponding influenza strain and is predictive of VE in children 6−35 months of age.

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