Specific IgE and IgG antibody responses in children to timothy pollen components during immunotherapy

Vaccination remains one of the most successful medical interventions in history, significantly decreasing morbidity and mortality associated with, or even eradicating, numerous infectious diseases. Although traditional immunization strategies have recently proven insufficient in the face of many highly mutable and emerging pathogens, modern strategies aim to rationally engineer a single antigen or cocktail of antigens to generate a focused, protective immune response. However, the effect of cocktail vaccination (simultaneous immunization with multiple immunogens) on the antibody response to each individual antigen within the combination, remains largely unstudied. To investigate whether immunization with a cocktail of diverse antigens would result in decreased antibody titer against each unique antigen in the cocktail compared to immunization with each antigen alone, we immunized mice with surface proteins from uropathogenic Escherichia coli, Mycobacterium tuberculosis, and Neisseria meningitides, and monitored the development of antigen-specific IgG antibody responses. We found that antigen-specific endpoint antibody titers were comparable across immunization groups by study conclusion (day 70). Further, we discovered that although cocktail-immunized mice initially elicited more robust antibody responses, the rate of titer development decreases significantly over time compared to single antigen-immunized mice. Investigating the basic properties that govern the development of antigen-specific antibody responses will help inform the design of future combination immunization regimens.

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Long-term persistence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein-specific and neutralizing antibodies in recovered COVID-19 patients

10.21203/rs.3.rs-1073046/v1 ◽

2021 ◽

Author(s):

Jira Chansaenroj ◽

Ritthideach Yorsaeng ◽

Nasamon Wanlapakorn ◽

Chintana Chirathaworn ◽

Natthinee Sudhinaraset ◽

...

Keyword(s):

Severe Acute Respiratory Syndrome ◽

Symptom Onset ◽

Neutralizing Antibodies ◽

Serum Antibody ◽

Neutralizing Antibody ◽

Antibody Responses ◽

Spike Protein ◽

Immunological Study ◽

Igg Antibody ◽

Vaccine Schedule

Abstract Understanding antibody responses after natural severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection can guide the coronavirus disease 2019 (COVID-19) vaccine schedule. This study aimed to assess the dynamics of SARS-CoV-2 antibodies, including anti-spike protein 1 (S1) immunoglobulin (Ig)G, anti-receptor-binding domain (RBD) total Ig, anti-S1 IgA, and neutralizing antibody against wild-type SARS-CoV-2 in a cohort of patients who were previously infected with SARS-CoV-2. Between March and May 2020, 531 individuals with virologically confirmed cases of SARS-CoV-2 infection were enrolled in our immunological study. The neutralizing titers against SARS-CoV-2 were detected in 95.2%, 86.7%, 85.0%, and 85.4% of recovered COVID-19 patients at 3, 6, 9, and 12 months after symptom onset, respectively. The seropositivity rate of anti-S1 IgG, anti-RBD total Ig, anti-S1 IgA, and neutralizing titers remained at 68.6%, 89.6%, 77.1%, and 85.4%, respectively, at 12 months after symptom onset. The half-life of neutralizing titers was estimated at 100.7 days (95% confidence interval = 44.5 – 327.4 days, R2 = 0.106). These results support that the decline in serum antibody levels over time depends on the symptom severity, and the individuals with high IgG antibody titers experienced a significantly longer persistence of SARS-CoV-2-specific antibody responses than those with lower titers.

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Assessment of the Sensitizing Potential of Proteins in BALB/c Mice: Comparison of Three Protocols of Intraperitoneal Sensitization

Nutrients ◽

10.3390/nu10070903 ◽

2018 ◽

Vol 10 (7) ◽

pp. 903 ◽

Cited By ~ 5

Author(s):

Jesús Arámburo-Galvez ◽

Norberto Sotelo-Cruz ◽

Lilian Flores-Mendoza ◽

Martina Gracia-Valenzuela ◽

Francisco Chiquete-Elizalde ◽

...

Keyword(s):

Milk Proteins ◽

Serum Levels ◽

Specific Ige ◽

Cow Milk ◽

Sample Collection ◽

Igg Antibody ◽

Allergenic Protein ◽

Ige Antibodies ◽

Undetectable Serum ◽

Specific Ige Antibodies

Most food allergy cases are associated with a limited group of allergens. This could be attributed to an increased ability of some foods to sensitize and trigger allergic reactions. However, there are no validated animal models to evaluate the sensitizing or allergenic potentials of proteins. Our aim was to evaluate three protocols of adjuvant-free intraperitoneal sensitization that differ in the time points for sample collection (days 14, 28 and 35 from beginning of the sensitization) and also in the number of immunizations (2, 5 and 3, respectively). Ovalbumin (OVA; 0.05 mg), cow milk proteins (CMP; 0.025, 0.05 and 0.25 mg), and potato acid phosphatase (PAP; low allergenic protein; 250.0 mg) were administered intraperitoneally (ip) to BALB/c mice (n = 4–6) and the protein-specific IgE and IgG antibody responses were evaluated using ELISA. Additional serum protein-specific IgE antibodies evaluations were carried out after IgG depletion. Anti-OVA IgE antibodies were detected in mice from all three protocols. The responses were higher in the group of mice that underwent the 28-day protocol than in those that underwent the 14- or 35-day protocols (p < 0.01 and p < 0.05, respectively). Anti-CMP IgE antibodies were detected in both the 14- and 28-day protocols, but the response was higher in the group that underwent the 28-day protocol (p < 0.001). The anti-CMP IgE antibody response detection was improved after serum IgG depletion (p < 0.001). Anti-PAP IgE antibodies were not detected. Mice with undetectable serum levels of protein-specific IgE triggered anti-OVA, -CMP, and -PAP IgG responses. An adjuvant-free 28-day protocol with five ip immunizations seems appropriate for evaluation of the inherent sensitizing or allergenic capacity of the studied proteins. Reproducible results were obtained utilizing the BALB/c mouse strain. Inter-laboratory studies including a larger number of proteins should be carried out to validate this model.

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Epitope-specific regulation. III. Induction of allotype-restricted suppression for IgG antibody responses to individual epitopes on complex antigens

European Journal of Immunology ◽

10.1002/eji.1830121004 ◽

1982 ◽

Vol 12 (10) ◽

pp. 814-818 ◽

Cited By ~ 7

Author(s):

Leonore A. Herzenberg ◽

Takeshi Tokuhisa ◽

Leonard A. Herzenberg

Keyword(s):

Antibody Responses ◽

Igg Antibody ◽

Specific Regulation

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Otitis Media in the Young Infant: An IgE-Mediated Disease?

Annals of Otology Rhinology & Laryngology ◽

10.1177/00034894800890s334 ◽

1980 ◽

Vol 89 (3_suppl) ◽

pp. 133-137 ◽

Cited By ~ 8

Author(s):

John L. Sloyer ◽

John H. Ploussard ◽

Laurel J. Karr

Keyword(s):

Otitis Media ◽

Otitis Media With Effusion ◽

Skin Testing ◽

Young Infant ◽

Specific Ige ◽

Serum Samples ◽

Igg Antibody ◽

Total Ige ◽

Ige Antibody ◽

The Mean

IgE antibody directed against noncapsular antigens of mechanically disrupted Streptococcus pneumoniae, serotype 3 rough, was demonstrated in middle ear effusions (MEE) and serum of infants with and without prior evidence of pneumococcal otitis media with effusion (OME). The techniques employed included radioimmunoassay (RIA), passive skin testing, Prausnitz-Küstner (P/K), and enzyme-linked immunospecific assay (ELISA). Adsorption of MEE with ultrasonically disrupted crude pneumococcal antigen (CPA-U) resulted in a reduction of total IgE counts per minute and suggested bacteria-specific IgE antibody ranging from approximately 22 to 92% of the total IgE. The biological activity of the IgE antibody was confirmed by challenging skin passively sensitized with MEE IgE and CPA-U. Areas of induration appeared 20 minutes after challenge and continued to increase in size until 90 minutes. An ELISA procedure was developed as a tool to determine the nature of the antigen(s) and to determine the class(es) of antibody other than IgE. It appeared that CPA-U possesses free amino groups and that it can withstand the rigors of autoclaving. An analysis of 45 cord bloods revealed that high levels of IgG CPA-U antibody occur in this type of sample and that no correlation exists between the IgE and IgG levels. The mean IgG: IgE ratio, optical density at 420 nm (OD 420), for cord bloods was 2.49. In contrast, serum samples from nine infants without pneumococcal otitis media and from 14 infants with pneumococcal otitis media had lower levels of IgG antibody. There was no significant relationship between IgG and IgE OD 420 in infants who never had an episode of pneumococcal otitis media and the mean IgG: IgE was 1.88, whereas the ratio for those infants with pneumococcal otitis media was 1.56. In addition, there was a significant correlation between IgG and IgE levels in this latter group. The results suggest that it may be important to monitor the levels of at least these two classes of antibody to enhance our understanding of the pathogenesis and recovery from otitis media.

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