Critical role of B cells in the development of T cell tolerance to aeroallergens (original) (raw)

Allergic airway sensitization induces T cell activation but not airway hyperresponsiveness in B cell-deficient mice

Proceedings of the National Academy of Sciences, 1997

B cells play an important role in the allergic response by producing allergen-specific Igs as well as by serving as antigen-presenting cells. We studied the involvement of B cells in the development of responses in a murine model of allergic airway sensitization. Normal and B celldeficient (Mt ؊͞؊ ) B10.BR mice were sensitized via the airways to ovalbumin; Ig production, cytokine elaboration from local lymph node cells, development of airway hyperresponsiveness, and histological changes in the airways were evaluated. Both strains of mice had increased production of T helper 2-like cytokines and developed an accumulation of eosinophils in the bronchial tissue after airway sensitization. However, only wild-type mice produced allergen-specific antibodies and exhibited altered airway function. B cell-deficient mice reconstituted with anti-ovalbumin IgE during the course of sensitization developed increases in airway responsiveness. These results indicated that neither B cells nor IgE were necessary for the induction of a T helper 2-type cytokine response or eosinophil infiltration of the airways after allergic sensitization but that IgE was required as a second signal for the development of airway hyperresponsiveness in this model of airway sensitization.

B cells play key roles in th2-type airway immune responses in mice exposed to natural airborne allergens

PloS one, 2015

Humans are frequently exposed to various airborne allergens. In addition to producing antibodies, B cells participate in immune responses via various mechanisms. The roles of B cells in allergic airway inflammation and asthma have been controversial. We examined the functional importance of B cells in a mouse model of asthma, in which mice were exposed repeatedly to common airborne allergens. Naïve wild-type BALB/c mice or B cell-deficient JH-/- mice were exposed intranasally to a cocktail of allergen extracts, including Alternaria, Aspergillus, and house dust mite, every other day for two weeks. Ovalbumin was included in the cocktail to monitor the T cell immune response. Airway inflammation, lung pathology, and airway reactivity were analyzed. The airway exposure of naïve wild type mice to airborne allergens induced robust eosinophilic airway inflammation, increased the levels of Th2 cytokines and chemokines in the lung, and increased the reactivity to inhaled methacholine. These ...

Regulatory Role of B Cells In a Murine Model of Allergic Airway Disease

The Journal of …, 2008

Mice sensitized to OVA and subjected to acute OVA aerosol exposures develop allergic airway disease (AAD). However, chronic continuous Ag exposure results in resolution of AAD and the development of local inhalational tolerance (LIT). Because we have previously observed ...

B Cell Antigen Presentation Promotes Th2 Responses and Immunopathology during Chronic Allergic Lung Disease

PLoS ONE, 2008

Background: The role of B cells in allergic asthma remains undefined. One mechanism by which B cells clearly contribute to allergic disease is via the production of specific immunoglobulin, and especially IgE. Cognate interactions with specific T cells result in T cell help for B cells, resulting in differentiation and immunoglobulin secretion. Proximal to (and required for) T cell-dependent immunoglobulin production, however, is antigen presentation by B cells. While interaction with T cells clearly has implications for B cell function and differentiation, this study investigated the role that B cells have in shaping the T cell response during chronic allergic lung disease.

Role of regulatory B cells in immune tolerance to allergens and beyond

The Journal of allergy and clinical immunology, 2016

Immune tolerance to both self-antigens and innocuous non-self-antigens is essential to protect the host against chronic inflammatory diseases and tissue damage. A wide range of cell types and suppressive molecules are involved in induction and maintenance of tolerance. In addition to their key function in the production of immunoglobulins, B cells can regulate immune responses through their surface molecules and secretion of cytokines. Regulatory B (Breg) cells are characterized by their immunosuppressive capacity, which is often mediated through IL-10 secretion. However, IL-35 and TGF-β have also been associated with B cell-mediated immunosuppression. Several types of murine and human Breg cells have been described, such as mouse CD5(+)CD1d(hi) B10 cells, CD21(hi)CD23(hi)CD24(hi) transitional stage 2-like B cells, and CD138(+) plasma cells and plasmablasts. Human Breg cell types include CD27(+)CD24(high) B10 cells, CD24(hi)CD38(hi) immature transitional B cells, and CD73(-)CD25(+)C...

Regulatory functions of B cells in allergic diseases

Allergy, 2014

B cells are essentially described for their capacity to produce antibodies ensuring anti-infectious immunity or deleterious responses in the case of autoimmunity or allergy. However, abundant data described their ability to restrain inflammation by diverse mechanisms. In allergy, some regulatory B-cell subsets producing IL-10 have been recently described as potent suppressive cells able to restrain inflammatory responses both in vitro and in vivo by regulatory T-cell differentiation or directly inhibiting T-cell-mediated inflammation. A specific deficit in regulatory B cells participates to more severe allergic inflammation. Induction of allergen tolerance through specific immunotherapy induces a specific expansion of these cells supporting their role in establishment of allergen tolerance. However, the regulatory functions carried out by B cells are not exclusively IL-10 dependent. Indeed, other regulatory mechanisms mediated by B cells are (i) the production of TGF-b, (ii) the promotion of T-cell apoptosis by Fas-Fas ligand or granzyme-B pathways, and (iii) their capacity to produce inhibitory IgG4 and sialylated IgG able to mediate anti-inflammatory mechanisms. This points to Bregs as interesting targets for the development of new therapies to induce allergen tolerance. In this review, we highlight advances in the study of regulatory mechanisms mediated by B cells and outline what is known about their phenotype as well as their suppressive role in allergy from studies in both mice and humans.

The effect of regulatory T cells on tolerance to airborne allergens and allergen immunotherapy

Journal of Allergy and Clinical Immunology, 2018

Forkhead box P3-positive regulatory T (Treg) cells are essential mediators of tolerance against self-antigens and harmless exogenous antigens. Treg cell deficiencies result in multiple autoimmune and allergic syndromes in neonates. How Treg cells affect conventional allergies against aeroantigens, which are restricted to a few specific proteins released from inhaled particles, remains controversial. The hallmarks of antigenspecific loss of tolerance are allergen-specific T H 2 cells and IgE. However, difficulties in identifying the rare allergen-specific Treg cells have obscured the cellular basis of tolerance to aeroallergens, which is also a major obstacle for the rational design of novel and more efficient allergen-specific immunotherapies. Recent technological progress allowing characterization of allergen-specific effectors and Treg cells with minimal in vitro manipulation revealed their detailed contribution to tolerance. The data identified inhaled particles as immunodominant Treg cell targets in healthy and allergic subjects. Conversely, the supposed immunodominant major allergens being rapidly released from inhaled particles apparently do not actively induce tolerance but are ignored by the immune system. Here, the partially contradictory data on various allergen-specific T-cell types in healthy subjects, allergic patients, and patients undergoing allergen-specific immunotherapy are discussed and integrated into one model, postulating Treg cell-dependent and Treg cell-independent checkpoints of tolerance and allergy development.

T and B cell responses to HDM allergens and antigens

Immunologic Research, 2007

House dust mites provide well-characterized proteins to study human responses to inhaled antigens. Even in the absence of allergy they induce a high frequency of T cell precursors. The healthy response manifests by T cell proliferation and Thl cytokines with little antibody. Responses of allergic people include Thl and Th2 cytokines and IgE, IgG 1, and IgG4 antibodies. Regulatory cells limit effector responses in healthy people. About half the IgE and IgG antibodies bind the group 1 and 2 allergens and 30% bind the group 4, 5, and 7 allergens. Although HLA independent, the recognition of the group 1 allergen show's an immunodolninant region and a T cell receptor bias. The major allergens a'e not produced in higher amounts than many of the poorly non-allergenic proteins. The non-allergenic mite ferritin antigen show's high T cell proliferative responses with mixed cytokine production.

Recruitment of circulating allergen-specific T lymphocytes to the lung on allergen challenge in asthma

Journal of Allergy and Clinical Immunology, 1997

Background: In allergie subjeets with asthma, the migration of CD4 + T cells to the lungs in the hours after allergen exposure may contribute to allergic inflammation in the target organ. Objective: We studied allergen-specific T cells from the peripheral blond and lungs of allergie subjects with asthma at baseline and after allergen challenge. Methods: In each patient, blood samples were taken 10 minutes before and 24 hours after the inhalation of a major sensitizing allergen. In vitro proliferation of peripheral blood CD4 ÷ T cells specific for the same ailergen used in the in vivo challenge was assessed. In one patient two Dermatophagoldes pteronyssinus-specific T-cell clones (TCCs) were derived from peripheral blood, and their T-cell receptors were sequenced to determine their clonotypic determinants on the B chains. The T-cell receptor determinants of the allergenspecific TCCs were sought in blood and bronchoalveolar lavage samples taken from this patient. Results: We found that allergen inhalation is followed by a decrement in the specific pro|iferation of peripheral CD4+ T cells to the same allergen used for bronchial provocation. In one patient the clonotypic determinants of two allergen-specific TCCs diminished in the peripherai blood, whereas they were simultaneously expanded in the lower respiratory tract. Conclusion: Our data suggest that allergen-specific T cells are recruited from the peripheral biood to the bronchial lumen after allergen ehallenge.