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Relationship: 1701
Title
Activation/Proliferation, T-cells leads to Increase, Allergic Respiratory Hypersensitivity Response
Upstream event
Downstream event
AOPs Referencing Relationship
| AOP Name | Adjacency | Weight of Evidence | Quantitative Understanding | Point of Contact | Author Status | OECD Status |
|---|---|---|---|---|---|---|
| Covalent Binding, Protein, leading to Increase, Allergic Respiratory Hypersensitivity Response | adjacent | High | Not Specified | Arthur Author (send email) | Under Development: Contributions and Comments Welcome | Under Development |
Taxonomic Applicability
Sex Applicability
| Sex | Evidence |
|---|---|
| Unspecific | High |
Life Stage Applicability
| Term | Evidence |
|---|---|
| All life stages |
In brief, once antigen has been processed and presented by DCs and Th2 cells activated (KEs 398 and 272), the differentiation and clonal expansion of Th2 cells lead to production of Th2 cytokines that induce immunoglobulin (Ig) class switching to production of antigen-specific allergic antibody (IgE) by B cells and clonal expansion of naive and memory B cell populations. (Dearman et al., 2003) These antibodies are then found throughout the body, in circulation and/or bound to Fce receptors on cells such as mast cells and basophils in tissues, including the respiratory tract. On subsequent re-exposure, antigen can crosslink IgE bound to the surface of the aforementioned cells and induce degranulation, releasing various mediators that lead to the clinical symptoms of asthma and rhinitis.
| ID | Experimental Design | Species | Upstream Observation | Downstream Observation | Citation (first author, year) | Notes |
|---|
| Title | First Author | Biological Plausibility |
Dose Concordance |
Temporal Concordance |
Incidence Concordance |
|---|
Biological Plausibility
Dose Concordance Evidence
Temporal Concordance Evidence
Incidence Concordance Evidence
Uncertainties and Inconsistencies
There is still remaining uncertainty regarding the role of IgE in chemical respiratory allergy, because specific IgE has not been demonstrated in all subjects sensitized to chemicals. (Kimber et al., 2014b, Kimber et al., 2014a, Quirce, 2014)
IgE production can occur both in the germinal centers of lymph nodes and locally in the airway mucosa, with the latter reported to be linked to nasal polyps associated with chronic rhinosinusitis and in response to inhaled protein allergens. (Baba et al., 2014, Hoddeson et al., 2010) The extent of germinal center involvement or local IgE production in respiratory sensitizers is currently unknown.
While there is considerable evidence that DCs are likely the most efficient APC for stimulating naive T cells, there is evidence that IgE at the surface of allergen-specific IgE-positive B cells and other APCs, such as alveolar macrophages, may also facilitate antigen presentation. (Zhong et al., 1997) A role for airway and alveolar epithelial cells in antigen presentation and induction and maintenance of adaptive responses is also becoming increasingly recognized. (Hasenberg et al., 2013)
Recent characterizations of the role of IL-21 in mouse models of protein allergy show that IL-21 promotes IgG1 in B cells when IL-4 is in low supply. This was supported by the finding that human ex-vivo naïve B cells from tonsils increased IgG1 but not IgE, suggesting that IgG1 may be associated with skin sensitization. (Gong et al., 2019) IL-21 was found to suppress the IgE response through IL-21R - STAT3 signaling in murine B cells. (Yang et al., 2020) However, these studies focused on murine models of allergy including dust mite and peanut, as well as a 4-hydroxy-3-nigrophenylacetyl-modified globulin, so the relevance of these mechanisms to low molecular weight chemical allergy is not clear.
| Modulating Factor (MF) | MF Specification | Effect(s) on the KER | Reference(s) |
|---|---|---|---|
| miR-155 | Type 2 innate lymphoid cells have been shown to be dependent on miR-155 to induce airway hyperresponse and IgE elevation in mice. Using a murine miR-155 KO model, mice who did not express miR-155 did not display these effects following dermal senstization to toluene diisocyanate, in contrast to control mice. | Blomme et al., 2020) |