the roles of inkt cells in asthma

พญ.รั�งสิ�มา เหรั ยญตรัะกู�ลIMMUNOLOGY DIVISION

DEPARTMENT OF MICROBIOLOGYFACULTY OF MEDICINE

CHULALONGKORN UNIVERSITY

The Role of iNKT Cells in Asthma

Allergic Bronchial Asthma

Inflammatory state: massive infiltration of eosinophils, lymphocytes and mast cells

Concomitant with various Th2 cytokines

Th2-biased responses

IL-13: inflammation initiator, goblet cell hyperplasia, AHR, airway fibrosis

IL-4: induction of Th2 responses???

NKT Cells

Discovery of NKT CellsDefinition of NKT CellsNKT cell RoleClassification of NKT Cells

Discovery of NKT Cells

Unexpected finding in examining the TCR repertoire of a series of suppressor T cell hybridomas

High frequency for a single TCR chain

V14 J18

Imai et al., 1986Koseki et al., 1989

Lantz and Bendelec, 1994Makino et al., 1995Cui et al., 1997

Presence of CD4-CD8- double negative (DN) cells expressing V8

CD44+, CD5+, NK1.1+Copious amounts of cytokine production

Budd et al., 1987Fowlkes et al., 1987Ballas and Rasmussen, 1990Sykes, 1990

V8+, CD5high and CD44+ thymocyte hybridoma has the mRNA for the V14 TCR chain

V14+ cells in peripheral tissues express V and NK1.1

Lantz and Bendelac. J.Exp.Med. 1994

Makino et al. Int. Immunol. 1995Taniguchi et al. Proc. Natl.Acad.Sci. 1996

“NKT Cell”

What is an NKT cell?

Recognizes Ag presented by class-I like MHC molecule CD1d, NK1.1, CD5+high, CD44+high

Usually semi-invariant TCR V14J18 TCR chain and most often V8 TCR chains

•True TCR T cells•NK markers

NKT Cell Role

Rapid cytokine response from preformed mRNA

NKT’s IL-4 could promote Th2 responses & IgE production

NKT cells recognize bacterial glycosphingolipids

Stetson et al. J.Exp.Med. 2003

IFN- IL-4

Yoshimoto et al. Science.1995

Kinjo et al. Nature., 2005

Classification of NKT Cells

Type I NKT Cells

•Invariant ab TCRs (Va14Ja18 in mice/Va24-Ja18 in humans)•CD1d restricted

Type II NKT Cells

•Diverse TCR repertoire•CD1d restricted

Type III NKT Cells

•MHC class I & II other than CD1d

Type I NKT Cells

Three properties:1. invariant V14J18 in mice/V24J18 in

humans2. limited repertoire of TCRs3. -GalCer recognition by CD1d

Other indefinite markers: NK1.1, Ly49 NK receptors, CD69, CD44

Kawano et al., 1997

Type I NKT Subsets

Human DN type I NKT cells Th1 cytokinesCD4+ type I NKT cells Th1 & Th2

cytokinesGumperz et al., 2002Lee et al., 2002a

iNKT Microbial Recognition

-glucoronosylceramide (-GalCer) Gram negative, LPS negative bacteria Sphingomonas species Ehrlichia species

Phosphoinositolmannoside (PIM) Mycobacteria

Leishmania glycoinositol phospholipidsSchistosome-derived glycoconjugate

Terabe M et al. Adv.Canc.Res. 2008

iNKT Self-Antigen Recognition

Glycosylphosphatidyl inositolsPhosphotidyl cholinePhosphotidyl inositol from soybeansPhospholipid from pollen a role in

allergy???Glycosphingolipid isoglobotrihexosylceramide

(iGb3)

Terabe M et al. Adv.Canc.Res. 2008

Asthma and NKT Cells

Essential role of NKT cells producing IL-4 and IL-13 in the development of allergen-induced airway hyperreactivity.

1. AHR fails to develop2. inability to produce Th2 responses3. adoptive transfer reverses the failure of

AHR development

Akbari et al. Nat Med 2003

Invariant V alpha 14 NKT cells are required for allergen are required for allergen-induced airway inflammation and hyperreactivity in an experimental asthma model.

1. impaired AHR2. adoptive transfer reconstitutes capacity to

develop asthma3. anti-CD treatment

Lisbonne et al. J.Immunol. 2003

iNKT Cells in the Induction of AHR

CD1d-/- mice fail to develop allergen-induced AHR

J18-/- mice failed to develop AHR and showed reduced airway eosinophilia

Yet, allergen-specific Th2-driven responses still develop normally.

Lisbonne et al. J.Immunol.2003

Akbari et al. Nat. Med. 2003

The Importance iNKT Cells in AHR Development

Anergized iNKT cell treatment prevent development of allergen-induced AHR

Direct activation of pulmonary iNKT cells were sufficient to induce AHR

Matsuda et al. Am.J.Respir.Cell.Mol.Biol.2005Hachem et al. Eur.J.Immunol.2005Morishima et al. Eur.J.Immunol. 2005

Meyer et al. Proc.Natl.Acad.Sci. 2006

AHR develops in absence of conventional CD4+ T cells and adaptive immunity, eosinophils, B cells

iNKT may not be required in all forms of AHR2-microglobulin-/- mice develops AHR

normally

Meyer et al. Annu.Rev.Med. 2008

Maeda et al. J.Immunol. 2004Zhang et al. J.Exp. Med. 1996

iNKT Cells in Human Asthma

Moderate-to-severe 14 persistent asthmatic patients, 5 stage II sarcoidosis, 6 healthy controls

Specimen: BALFStaining of iNKT with CD1d tetramer loaded

with -GalCer and 6B11 mAb

CD4+ Invariant T-Cell-Receptor+ Natural Killer T Cells in Bronchial Asthma

Akbari O et al. NEJM. 2006

Staining of FITC 6B11 mAb


Red: phycoerythrin-conjugated CD4Blue: FITC 6B11 mAbPink: Overlay Akbari O et al. NEJM. 2006

Corticosteroid-treatedCorticosteroid-untreated


RT-PCR


One subgroup of iNKT cells is selectively recruited or expanded in lungs of bronchial asthmatic patients.



Specimen: peripheral V24i NKT cells

V alpha 24-invariant NKT cells from patients with allergic asthma express CCR9 at high frequency and induce Th2 bias of CD3+ T cells upon CD226 engagement

Sen Y et al . J.Immunol. 2005

87%


Highly increased frequency of asthmatic CCR9-expressing V24i NKT cells


CCR9 and V24i NK T cell distribution


Asthmatic CCR9-expressing V24i NKT cells induced Th2 biasin CD3 T cells

IL-4 IL-13


IL-4 IL-13


Confirm the function of different V24i NKT cells

IL-4

IL-13


Transwell stimulationsSen Y et al . J.Immunol. 2005

CD226 expression in V24i NKT cells


CCR9 and CD226 activation


Kay AB.NEJM. 2006

The Two Pathways

iNKT Cells in the Current Asthma Model

Umetsu. Nature. 2006


Five of the seven reports confirm that the lungs of asthmatic patients contain more iNKT cells than normal controls

Spinozzi et al. Immmunol. Allergy Clin. North Am. 2007Pham-Thi N et al. JACI. 2006Pham-Thi N et al. NEJM. 2006Hamzaoui A et al. Mediat. Inflamm. 2006Sen Y et al. J. Immunol. 2005

The other two reports concluded that iNKT cells are not increased in asthma

Up to 2% of the T cells in the lungs of asthmatic patients are iNKT cells

Thomas SY et al. NEJM. 2006Vijayanad P et al. NEJM. 2007

A new report suggesting the number of pulmonary iNKT cells may not relate to asthma severity and control.

5 severe, 8 well-controlled, 5 non-asthmatic patients

BALF analyzed by flow cytometry and stained with PBS57 and anti-CD3-Alexa750

Natural killer T Cells in the lungs of patients with asthma

Umetsu et al. JACI. 2009

Adjusted percentages of iNKT cells/Tcells

Asthma Phenotypes

Mild-moderate asthma

Persistent severe asthma

Th2 cell iNKT cell

iNKT cell

Therapeutic Potentials

ControversialGlycolipid therapy

IV administration shift towards Th1 cytokine response

Intranasal administration induces Th2 polarization and worsens eosinophilic infiltration and induces AHR

Oki and Miyake. Allergol.Internat. 2007

Thank You!

the roles of inkt cells in asthma

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