Post-vaccination IgG4 and IgG2 class switch associates with increased risk of SARS-CoV-2 infections

Journal of Infection, Journal Year: 2025, Volume and Issue: unknown, P. 106473 - 106473

Published: March 1, 2025

Language: Английский

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Frequency of IgE antibody response to SARS-CoV-2 RBD protein across different disease severity COVID19 groups

Virology Journal, Journal Year: 2025, Volume and Issue: 22(1)

Published: March 4, 2025

COVID-19 appears to have a progression of three stages. The latter stage is characterized by high level cytokine release, which in turn triggers an uncontrolled reaction known as storm where mast cells are involved. presence anti-IgE antibodies against SARS-CoV-2 this phase has been previously reported, suggesting association with the severity disease. Our study aims assess prognostic significance IgE across spectrum clinical presentations, including individual mild symptoms, hospitalized patients, and those who presented critical progression. included 64 patients distributed into following groups: 22 critically ill individuals (Critical); 21 non-critical (Severe); symptomatic non-hospitalized cases (Mild); healthy blood donors samples collected October 2019. Anti-IgE Spike (S) protein were detected using homemade ELISA, plate was sensitized RBD recombinant S protein. Among infected 28.1% tested positive for isotype RBD, whose prevalence similar Mild 23.8%, Severe 28.6%, Critical 31.8% (p = 0.842). Patients response exhibited higher levels LDH compared non-IgE responders, 40% increase 0.037), non-significantly tendency other inflammatory markers. In infection, roughly fourth response, regardless disease severity, associated LDH.

Language: Английский

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Does SARS-CoV-2 Possess “Allergen-Like” Epitopes?

COVID, Journal Year: 2025, Volume and Issue: 5(4), P. 55 - 55

Published: April 16, 2025

An increase in immunoglobulin G4 (IgG4) levels is typically associated with immunological tolerance states and develops after prolonged exposure to antigens. Accordingly, IgG4 considered an anti-inflammatory antibody a limited ability trigger efficient immune responses. Additionally, reduces allergic reactions by blocking E (IgE) activity. In the case of COVID-19, it has been reported that repeated administration some vaccines induces high levels. The latest research data have revealed surprising IgE anti-receptor binding domain response both natural infection several SARS-CoV-2 vaccines. presence COVID-19 disease suggests virus may induce “allergic-like” evade surveillance, leading shift from T helper 1 (Th1) 2 (Th2) cells, which promotes potentially contributes chronic infection. spike protein could also such response. Interestingly, “allergen-like” epitopes responses for other viruses, as influenza, human immunodeficiency (HIV), respiratory syncytial (RSV). impact this viral-induced will be discussed, concerning long COVID protective efficacy

Language: Английский

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IgE in the Regulation of Adaptive Immune Responses

Immunological Reviews, Journal Year: 2025, Volume and Issue: 331(1)

Published: May 1, 2025

ABSTRACT Immunoglobulin E (IgE) plays a dual role in the immune system, providing protection against pathogens while also mediating pathological hypersensitivity reactions. Its function is mainly studied context of immediate inflammatory responses, where IgE‐sensitized effector cells, such as mast cells and basophils, are triggered by cross‐linking antigen. An often‐overlooked feature IgE biology its strong ability to boost secondary adaptive thus acting physiological adjuvant. The regulation these responses influenced various factors, including primary Ig structure, post‐translational modifications glycosylations, structural properties antigens, interaction with receptors. Interestingly, not only generates antigen‐specific but IgE‐specific autoimmune responses. Natural IgG anti‐IgE autoantibodies circulate at surprisingly high levels, even healthy individuals, contributing serum levels Understanding emerging concepts, beyond singular focus on initial production cell activation, could contribute better understanding immunological functions IgE. In this review, we aim provide an overview current knowledge immunogenicity. Many open questions remain negative positive feedback mechanisms which regulates response, hope inspire future research into underlying IgE‐regulated their potential implications for therapeutic strategies diseases.

Language: Английский

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Mechanisms and Implications of IgG4 Responses to SARS-CoV-2 and Other Repeatedly Administered Vaccines

Journal of Infection, Journal Year: 2024, Volume and Issue: unknown, P. 106317 - 106317

Published: Oct. 1, 2024

Language: Английский

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