Non-IgE-mediated allergic diseasesSummary
Markus Rudowitz
Faculty of chemistry and biochemistryMolecular Immunology 2016Wed 6th of July, 2016
Source: http://library.med.utah.edu/WebPath/jpeg4/GI162.jpg (04.07.2016) Source: Murphy, Kenneth: Janeway‘s Immunobiology, 8th Edition, p. 604
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Non-IgE-mediated allergic diseases Type II (e.g. penicillin allergy hemolytic anemia or thrombocytopenia) +
type III (soluble antigens, immune complexes; e.g. Arthus reaction, serumsickness): IgG mediated
Type IV: antigen specific TH1 or CD8T cells (TH2 similar to IgE-mediated allergic diseases; e.g. tuberculin test, poison ivy, nickel,allergic contact dermatitis,celiac disease)
Non-IgE-mediated allergic diseases Markus Rudowitz | RUB | 06.07.2016
Modified from: Murphy, Kenneth: Janeway‘s Immunobiology, 8th Edition, p. 594
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Non-IgE-mediated allergic diseases
Arthus reaction: local type III hypersensitivityreaction
Triggered in skin by contact with sensitizing antigen Also activation of the complement: complement fragment C5a
Non-IgE-mediated allergic diseases Markus Rudowitz | RUB | 06.07.2016
Source: Source: Murphy, Kenneth: Janeway‘s Immunobiology, 8th Edition, p. 599
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Non-IgE-mediated allergic diseases
Tuberculin test (type IV hypersensitivity reaction)
Non-IgE-mediated allergic diseases Markus Rudowitz | RUB | 06.07.2016
Source: Murphy, Kenneth: Janeway‘s Immunobiology, 8th Edition, p. 601
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Non-IgE-mediated allergic diseases
Allergic contact dermatitis and systemic allergic contact dermatitis (type IV hypersensitivity reaction)
Non-IgE-mediated allergic diseases Markus Rudowitz | RUB | 06.07.2016
Source: Murphy, Kenneth: Janeway‘s Immunobiology, 8th Edition, p. 602
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Non-IgE-mediated allergic diseases
Celiac disease
Mediated by gluten; α-gliadin modified by tissue transglutaminase (tTG) tobind HLA-DQ2
Strong genetic predisposition: >95% of patients express HLA-DQ2 class MHC allele
loss of mature epithelial cells in upper small intestine, severe inflammation, increased number of T cells, macrophages, plasma cells in the lamina propria; increased number of lymphocytes in epithelial layer
Non-IgE-mediated allergic diseases Markus Rudowitz | RUB | 06.07.2016
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Source: Murphy, Kenneth: Janeway‘s Immunobiology, 8th Edition, p. 605
Non-IgE-mediated allergic diseases
Non-IgE-mediated allergic diseases Markus Rudowitz | RUB | 06.07.2016
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Non-IgE-mediated allergic diseases
Celiac disease
has some features of autoimmunity!
Autoantibodies (IgA) against tTG in all patients used as test
No tTG-specific T cells found; gluten-reactive T cells may help B cells reactiveto tTG
Non-IgE-mediated allergic diseases Markus Rudowitz | RUB | 06.07.2016
Source: Murphy, Kenneth: Janeway‘s Immunobiology, 8th Edition, p. 605
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Non-IgE-mediated allergic diseases
Celiac disease
Reasons for pathology of gluten: relative resistant to digestion, gliadin-derivedpeptides stimulate innate immune system by inducing IL-15 release byintestinal epithelial cells
antigen-nonspecific process that involves peptides notbound by HLA-DQ2 and not recognized by CD4 T cells
IL-15: upregulation of MIC-A expression in epithelial cellsMIC-A activates CD8 T cells via NKG2D receptors that
can kill MIC-A expressing cells
Source: Murphy, Kenneth: Janeway‘s Immunobiology, 8th Edition, p. 606
Non-IgE-mediated allergic diseases Markus Rudowitz | RUB | 06.07.2016