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

Nahir Nahir Gar Garaba batos, s, PhD PhD

Po Postd 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

ROLE OF IL‐33 IN MODULATING HUMAN ALLERGEN SPECIFIC PATHOGENIC CD4+T CELL RESPONSES

IL‐33 plays an important role in allergy and inflammation

• 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.

• IL‐33,

also called alarmin, is a pro‐ inflammatory cytokine induced by inflammatory stimulation leading to Type 2 immune responses in tissue epithelial cells.

Paula Licona‐Limón et al. Nature Immunology 14, (2013).

(Endo Y et al Immunity 2015 Feb 17;42(2):294-308) Kurowska M., J Immunol Oct, 2008, 181 (7) 4780-4790 Smithgall MD et al. Int Immunol 2008 Aug;20(8):1019-30

• 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

• nly

a subset

• f

the cytokines responsible for atopic diseases.

A distinct TH2 cell subset is associated with type I allergic diseases

 TH2A cells constitute potential biomarker and therapeutic target

CRTH2 CD161

TH2A cell subset

CRTH2 CD161 CD27 CD49d CD27 CD49d CD45RB CD4 CD45RB CD4

Allergic individuals Non-atopic individuals

35% 35%

• CD27 expression distinguishes a protective (CD27+) from a pathogenic (CD27‐) allergen specific T cell

response developed in different allergy disorders.

• 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. J Allergy Clin Immunol. 2014 Mar;133(3) Wambre et al. J Allergy Clin Immunol. 2012 Feb;129(2) Wambre et al. Clin Immunol. 2015 Nov 161 (1)

10 000 1 000 100 # TH2A cells per 106 memory CD4+ T cells P=0.001 10

TH2A cell subset

Allergic disease related differences emerged in the TH2 cell responses

 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).

PPARG

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).

Fresh Whole Blood

PBMC isolation

PBMC Culture + Peanut Extract +/- IL-33

CD154 staining & Abs labelling procedure

O.N. Incubation

CD154 Positive Fraction CD154 Negative Fraction

+/- Monensin

• Peanut reactive

CD4+ T cells (CD154+CD27+/-)

• TH2A (CD27- CRTH2+CD161+CD4+)
• TH2 (CRTH2+CD161-CD4+)
• 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.

Peanut specific TH2A cells express high RNA levels of IL‐33 Receptor

 Peanut specific TH2 cells are include within TH2A subset.  Peanut reactive T cells (CD154+) from patients fall into 2 subsets according to CD27 expression.

Within Peanut Reactive (CD154+ ) Memory CD4+ T cells

 Peanut‐reactive TH2A cells (CD27 negative) express high mRNA levels of IL33 Receptor.

IL‐33 R (ST2)

FC (Relative Units)

20 40 60 80 100 % peanut-specific T cells

 Upon TCR stimulation, allergen‐specific TH2 cells up‐regulated expression of IL‐33 Receptor.

CD27 CRTH2 CD161

CD154

Cytokine profiles between CD27‐ and CD27+ allergen‐specific T cell subsets are highly divergent:

CD154+CD27- CD154+CD27+

IL‐5 IL‐9 IL‐13 IL‐4 CD154 CD27

Peanut Reactive T cells CD154+

 CD27 negative Peanut specific T cell subset secrete higher level of the cardinal Type 2 effector cytokines than their CD27 positive counterpart

N=10 Peanut Patients IL‐4 IL‐5 IL‐9 IL‐13

CD27‐ peanut specific T cells CD27+ peanut specific T cells

IL‐33 enhance pro‐inflammatory function of allergen specific TH2A cell responses

CD154‐ TH2A cell subset CD154+ TH2A cell subset IL‐4 IL‐5 IL‐9 +IL33

 Upon TCR stimulation, IL‐33 regulate the pathogenicity of allergen‐specific CD4+ TH2A cells.

+IL33

Allergen specific TH2A cells are critical target of IL‐33 in allergic inflammation

N=10 Peanut Patients

IL‐5 IL‐4

‐ IL‐33 + IL‐33

 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

 Upon TCR stimulation, IL‐33 selectively enhances TH2 cytokine expression and production by allergen‐specific TH2A cells

N=2 Peanut Patients IL‐5 IL‐4 IL‐13 Extract Xtr+IL‐33

Allergen specific TH2A cells are critical target of IL‐33 in allergic inflammation

IL‐33 represent an attractive therapeutic target

APC

Peanut

IL‐33

Tissue

ILC2 Mast Cell

APC Lymph nodes

TCR

Peanut TH2A

TH2 Differentiation And activation

Peanut TH2A

IL‐5 IL‐4 Expression of effector cytokines by allergen‐ specific TH2 cells depends on IL‐33 cytokine at sites of tissue damage, revealing a tissue checkpoint that regulates allergic immunity.

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 TH2A 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

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