ROLE OF IL 33 IN MODULATING HUMAN ALLERGEN SPECIFIC PATHOGENIC CD4+T - PowerPoint PPT Presentation

ROLE OF IL ‐ 33 IN MODULATING HUMAN ALLERGEN SPECIFIC PATHOGENIC CD4+T CELL RESPONSES Nahir Gar Nahir Garaba batos, s, PhD PhD Postd Po stdoctoral Re Research Associa Associate Dr Dr. Erik Erik Wa Wambre’s Lab Benar Benaroya Resea search ch In Institute, Sea Seattle tle WA WA

IL ‐ 33 plays an important role in allergy and inflammation • IL ‐ 33, also called alarmin , is a pro ‐ inflammatory cytokine induced by inflammatory stimulation leading to Type 2 immune responses in tissue epithelial cells. • IL ‐ 33 mediates its biological effects via IL ‐ 1 receptor ‐ like 1 (ST2). • IL ‐ 33 acts on several cell types as a central mediator of atopic diseases including: food allergies, asthma and atopic dermatitis. • Because IL ‐ 33 acts upstream in the type ‐ 2 immune cascade, it represent an attractive therapeutic target for the treatment of atopic diseases over competing agents that block only a subset of the cytokines Paula Licona ‐ Limón et al. Nature Immunology 14, (2013). responsible for atopic diseases. Smithgall MD et al. Int Immunol 2008 Aug;20(8):1019-30 Kurowska M., J Immunol Oct, 2008, 181 (7) 4780-4790 (Endo Y et al Immunity 2015 Feb 17;42(2):294-308)

A distinct TH2 cell subset is associated with type I allergic diseases Allergic individuals 10 000 P =0.001 35% TH2A cell memory CD4+ T cells subset # TH2A cells per 10 6 CD49d CRT H 2 CD4 1 000 CD27 CD45RB CD161 Non-atopic individuals 100 35% TH2A cell subset CD49d CRT H 2 10 CD4 CD161 CD27 CD45RB • CD27 expression distinguishes a protective (CD27+) from a pathogenic (CD27 ‐ ) allergen specific T cell response developed in different allergy disorders. Wambre et al. J Allergy Clin Immunol. 2012 Feb;129(2) Wambre et al. J Allergy Clin Immunol. 2014 Mar;133(3) • TH2A cell subset ( CRTH2+, CD161+, CD27 ‐ , CD45RB ‐ and CD49d+) represents a phenotypically distinct TH2 subpopulation confined to atopic individuals, which encompass the vast majority of pathogenic (CD27 ‐ negative) allergen ‐ specific TH2 cells involved in type I allergic diseases. Wambre et al. Clin Immunol. 2015 Nov 161 (1)  TH2A cells constitute potential biomarker and therapeutic target

Allergic disease related differences emerged in the TH2 cell responses PPARG  TH2A cell subset produced more transcript of IL ‐ 5 and IL ‐ 9 compared to conventional TH2 cells.  They also selectively expressed IL ‐ 33R (IL1RL1 or ST2) and may differentially contribute to atopic diseases (TH2 driven pathology). Wambre et al. Clin Immunol. 2015 Nov 161 (1)

Role of IL ‐ 33 in promoting the activity of peanut ‐ specific TH2A cells: Methods • Peanut Allergy was used as an experimental model (10 peanut allergic patients). • CD154 upregulation following short stimulation of PBMCs with Peanut extract was used to track peanut reactive T cells and evaluate influence of recombinant IL ‐ 33 on functional properties of peanut ‐ reactive CD4+ T cell subsets. CD154 staining & Abs labelling CD154 procedure Positive Fraction PBMC isolation O.N. Incubation  Peanut reactive CD4+ T cells (CD154+CD27+/-) +/- Monensin Fresh PBMC Culture Whole Blood + Peanut CD154 Extract  TH2A (CD27- CRTH2+CD161+CD4+) Negative  TH2 (CRTH2+CD161-CD4+) Fraction +/- IL-33

Peanut specific TH2A cells express high RNA levels of IL ‐ 33 Receptor Within Peanut Reactive (CD154+ ) Memory CD4+ T cells CD154 IL ‐ 33 R (ST2) FC (Relative Units) CD27 CRTH2 CD161 100 % peanut-specific T cells 80 60 40 20 0  Peanut reactive T cells (CD154+) from patients fall into 2 subsets according to CD27 expression.  Peanut specific TH2 cells are include within TH2A subset.  Peanut ‐ reactive TH2A cells (CD27 negative) express high mRNA levels of IL33 Receptor.  Upon TCR stimulation, allergen ‐ specific TH2 cells up ‐ regulated expression of IL ‐ 33 Receptor.

Cytokine profiles between CD27 ‐ and CD27+ allergen ‐ specific T cell subsets are highly divergent: IL ‐ 4 IL ‐ 5 IL ‐ 9 IL ‐ 13 Peanut Reactive T cells CD154+ CD154+CD27+ CD27 CD154+CD27- CD154 N=10 Peanut Patients CD27 ‐ peanut specific T cells  CD27 negative Peanut specific T cell CD27+ peanut specific T cells subset secrete higher level of the cardinal Type 2 effector cytokines than their CD27 positive counterpart IL ‐ 4 IL ‐ 5 IL ‐ 9 IL ‐ 13

IL ‐ 33 enhance pro ‐ inflammatory function of allergen specific TH2A cell responses CD154+ TH2A cell subset CD154 ‐ TH2A cell subset +IL33 +IL33 IL ‐ 5 IL ‐ 9 IL ‐ 4  Upon TCR stimulation, IL ‐ 33 regulate the pathogenicity of allergen ‐ specific CD4+ TH2A cells.

Allergen specific TH2A cells are critical target of IL ‐ 33 in allergic inflammation IL ‐ 4 IL ‐ 5 ‐ IL ‐ 33 + IL ‐ 33 N=10 Peanut Patients  IL ‐ 33 selectively amplify peanut specific TH2A cell responses  As expected in adaptive immunity, IL ‐ 33 ‐ induced upregulation of IL ‐ 4 and IL ‐ 5 require previous TCR triggering

Allergen specific TH2A cells are critical target of IL ‐ 33 in allergic inflammation Extract Xtr+IL ‐ 33 N=2 Peanut Patients IL ‐ 5 IL ‐ 4 IL ‐ 13  Upon TCR stimulation, IL ‐ 33 selectively enhances TH2 cytokine expression and production by allergen ‐ specific TH2A cells

IL ‐ 33 represent an attractive therapeutic target Peanut Tissue IL ‐ 33 ILC2 Mast Cell IL ‐ 5 APC IL ‐ 4 Peanut TH2A Lymph nodes Expression of effector cytokines by allergen ‐ TCR APC Peanut specific TH2 cells depends on IL ‐ 33 cytokine at TH2A sites of tissue damage, revealing a tissue checkpoint that regulates allergic immunity. TH2 Differentiation And activation

Conclusions  TH2A cell subset represents a phenotypically and functionally distinct TH2 subpopulation in atopic individuals that includes all allergen ‐ specific TH2 cells and specifically express IL ‐ 33 receptor (ST2).  Production of effector cytokines by activated allergen ‐ specific T H 2A cells is modulated by IL ‐ 33.  As an enhancer of allergic immune response, IL ‐ 33 represent an attractive therapeutic target in the treatment of atopic diseases over competing agents that block only a subset of the cytokines responsible for atopic diseases.

Acknowledgements Wambre laboratory: Anaptys Bio: Erik Wambre Marco Londei Veronique Bajzik Blake Rust Kelly Aldridge Sam Skinner Hannah Deberg Virginia Mason: David Robinson Mary Farrington David Jeong Genomic core: Kimberly O’Brien Peter Linsley Vivian Gersuk Clinical core: Gina Marchesini Kavitha Gilroy