Generation of CNS-1 deficient mice

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Allergy, atopy and asthma Rich
Locksley Micro 204 December 2014
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Allergy and asthma cells and cytokines timeline
1879 1913
1921 1967
1983 1986 1991 1992 1998
2002 2009-
Eos, basos, mast cells Paul Ehrlich
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Global burden of allergic pathology
Developed Countries Developing
Countries

• Parasitic helminth infections
• Intestinal nematodes (gt2 billion)
• Tissue filaria (gt120 million)
• Tapeworms (gt2 million)
• Schistosomes (gt200 million)
• Major causes of liver failure, bladder cancer,
  elephantiasis, blindness, epilepsy
• (post-reproductive morbidity)

• Asthma and Allergy
• gt300 million worldwide
• Asthma prevalence increased 75 from 1980-1994
• gt70 asthma patients have allergy
• 18-12 US children
• gt20 billion/yr health care costs US

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A word about helminths
Account for 80 of all individual animals on
earth Estimates up to 106 species Three major,
two minor clades - all includes parasitic
species 2.9 billion humans estimated
infected Universal in rural subtropical
environments typical of human evolution Essentiall
y universal in feral vertebrates (mammals, birds,
fish, reptiles, amphibians) Genome size 20,000
If type 2 immunity protects us from helminths, it
doesnt do a very good job Maybe helminths
exploit the pathway for other things
Parkinson J, et al. 2004. A transcriptome
analysis of the phylum Nematoda. Nature Genet
361259-67.
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Ana - phylaxis Backwards Protection
Richet 1913 Nobel Prize
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Allergy
An adverse immune response to environmental
antigens (allergens).
Operational definition IgE
Manifestations Anaphylaxis, Eczema, Hayfever,
Asthma
Insect venoms Pollens Mite feces Animal
danders Food Haptenylated drugs (penicillin)
Many Allergens Acquired Via the Mucosa
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IgE Reagin or Reaginic Antibodies PCA
Passive Cutaneous Anaphylaxis
Serum (IgE) (Ishizaka, 1966)
Atopic to Antigen X
aIgE
Non-Atopic
Antigen X
Immediate Hypersensitivity
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Stages of Allergy - I.
Early Phase Reaction - minutes
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Stages of Allergy - II.
Late Phase Reaction - hours
a4
CCR8
TNF
Th2
PGD2
IL-4 IL-13
IL-5
IL-3 IL-9
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Stages of Allergy - II.
Late Phase Reaction - hours
a4
CCR8
TNF
Th2
PGD2
Mast cell
IL-13
ILC2 cell
GM-CSF
IL-5
IL-9
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Stages of Allergy - III.
Chronic Phase Reaction - wks - yrs
1. Subepithelial Fibrosis
TGF-b Toxic Granules
2. Smooth Muscle Hypertrophy
3. Mucosal and Mast Cell Hyperplasia
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FceRI Key Player

IgE Kd 10-10 M
a
gg
b
Syk
P
P
Lyn
PI(3)K
P
LAT
AA
PLA-2
Btk/Itk
PIP3
GADS/SLP-76
PLCg1
VAV
Ca
Ras
Rab
MAPK
PGD2 LTC4
Granule Exocytosis
Cytoskeleton
TNF IL-4
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Mouse Human
Mouse IgG1/FcgRIII on mast cells can trigger
pathway (not present on human mast cells)
Human APC, Eosinophils
ag2 FceRI
a
gg
IgE-linked antigen presentation in human
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How do perivascular mast cells acquire serum
IgE? ..they reach in and take it
Mast cell (green) around a blood vessel (white
outline) extending a process into the lumen to
bind an IgE-coated bead. Cheng et al, Immunity
38166-75, 2013
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Mast Cell Granules
Histamine Vasodilator Edema Heparin
Bonds constituents (negative charge) Neutral
Serine Proteases Tryptase All Chymase
Carboxypeptidase Cathepsin G
C.T. gt mucosal
Knock-out no mast cell granules
Dudeck A et al, Immunity 34973-84, 2011
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Myeloid Cell Eicosanoids
Ca
IgE
AA
FLAP
LTA4
LTC4 synthase in asthma
5-LO
Mast Cells Eosinophils Basophils AAM?
PLA2
LTC4
LTA4 Hydrolase
PMN M?
Transpeptidase
LTB4
LTD4
chemoattractant
Dipeptidase
(SRS-A)
CysLT1,CysLT2
LTE4
BLT1 BLT2
Smooth Muscle Contraction Endothelial NO Mucus
Secretion
Cell Recruitment
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Leukotriene Receptors
BLT1 LTB4 (Kd0.5 nM) Gene duplication Myeloid,
lymphoid cells Tissue 14q
(h) recruitment BLT2 LTB4 (Kd23 nM),
More widely
other eicosanoids CysLT1 LTD4gtC4E4
X (h) PBL, lung
smooth muscle, Vascular
lung macrophages, relaxation smooth


small intestine
muscle contraction cell
activation CysLT2 LTC4LTD4gtE4 13q14 (h)
PBL, lung, heart, brain Cell
activation
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Mast Cell PGD2
Ca
IgE
in asthma
AA
COX
PGD2
PLA-2
DP1 Kd 1.5 nM (airway epi, basophils,smooth
muscle lung, GI)
CRTh2 (DP2) Kd 2.5 nM (Th2, eo, baso,ILC2,
lung smooth muscle, GI)
Mouse ko lung inflammation, bronchial
hyperreactivity Mouse ko skin allergic
hypersensitivity
Bronchoconstriction Chemokines
(Eotaxins, MCPs, MDC)
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Eosinophil Granules
Specific Primary
Major Basic Protein Eosinophil Cationic Protein
(RNase3) Eosinophil Peroxidase Eosinophil-derived
Neurotoxin (Rnase 2) Lysophospholipase (Charcot-L
eyden crystals)
CYTOTOXICITY (multi-system toxicity in patients
with idiopathic HES)
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Eosinophils and airway remodeling
Less subepithelial and interstitial collagen
deposition in sensitized mice lacking eosinophils
(Humbles et al., Science 3051776, 2004)
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Asthma
Prevalence gt300 million worldwide 1/6 U.S.
children Cost in U.S. gt 6 billion/yr ing
Developed gt Nondeveloped Countries
Hygiene Hypothesis Reflects developmental
evolution of mucosal/regulatory immune system,
possibly through effects on establishing the
commensal flora ?Worms, ectoparasites,
childhood infections
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Asthma an epidemic in the absence of
infection Inverse relationship between
infections and immune disorders
Bach JF. 2002. N Engl J Med. 347911.
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Asthma Triad
1. Reversible episodes airway obstruction (
mucus, eosinophils, T cells with IL-4, IL-5,
IL-13, GM-CSF, etc.) 2. Chronic airway
inflammation ( T cells, eosinophils with
type 2 cytokines chronic subepithelial,
epithelial changes with mucus cell
hyperplasia) 3. Bronchial hyperreactivity with
provocative agents
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The global epidemic of asthma
Masoli et al., The global burden of asthma
executive summary of the GINA dissemination
committee report. Allergy 59469-78, 2004

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A disease of persistent Th2-associated airway
inflammation
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Innate cytokines in Type 2 immunity
Sullivan et al, Nature Immunology 2011
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Type 2 immunity as a confluence of innate and
adaptive responses to epithelial insults and
why no Tregs? (prominent in helminth infection)
ILC2 cells
Locksley, Cell 140777-783, 2010
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Innate lymphoid cells, 2014
ILC1
ILC2
ILC3
Group 1 T-bet
Group 2 GATA3hi
Group 3 ROR?t
IEL ILC1
NK-22
Natural helper cells Nuocytes Ih2
ILC1
cNK
Ex-ROR?t
LTi
IFN?
IL-5 IL-13
IL-17A IL-22
IFN?
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Unexpected roles for ILC2s (and probably Th2s)
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ILC2s sustain resident eosinophils and AAMs
needed for metabolic homeostasis Wu et al,
Science 2011 Molofsky et al, J Exp Med
2013 Role for eosinophils and AAMs in brown fat
(adaptive thermogenesis) and beige fat
consistent with role for ILC2s Nguyen et
al, Nature 2011 Qui et al, Cell 2014
Rao et al, Cell 2014 Lee et al, Cell (in
press)
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ILC2s integrate diverse signals to dynamically
regulate tissue microenvironments
Lipid mediators
IFN-g
Circulating eosinophils
CysLTs
IL-5
VIP
Neuropeptide transmitters
IL-9, GM-CSF Amphiregulin
IL-13
AAMs Local eosinophils
IL-25, IL-33, TSLP
IL-2, IL-7, IL-9, TL1A
AAM
Treg homeostasis
Cytokines
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Birds of a feather
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Do worms exploit type 2 immunity for their own
metabolic and tissues needs?
Chitin in egg shells and pharyngeal feeding tube
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Asthma GWAS
Asthma GWAS
Moffat MM et al, NEJM 3631211-21, 2012
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Mouse 'Asthma'
OVA
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Therapy of human asthma
Approved in clinic Steroids and beta-agonists
(long- and short-acting) - mainstay 5-LO
inhibitors (LTA4 synthesis blockers) CysLTI
antagonists (LTD4 blockers) Monoclonal humanized
anti-IgE mAb (E25) Anti-IL-5 (decrease disease
in high-eo subsets, usually steroid-resistant) An
ti-IL-13 (in Th2-high signature asthmatics) In
development/testing anti-TSLP (clinical trial
promising) Suplatast tosilate (suppresses IL-4,
IL-5 from Th2 cells) CDP840, phosphodiesterase
type 4 inhibitor IL-4 receptor, IL-4/13
inhibitors, anti-IL-5R OX40L blockade anti-TNF
(steroid resistant asthma), IL-17
inhibitors anti-IL-33
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Topics for discussion
Asthma reaches prevalence levels of 8-12 in
some urban Westernized populations. Allergic
asthma is predominantly a disease of childhood.
Consider the impact of genetics, environment and
development in constructing a model to explain
the immunologic underpinnings explaining the
increasing prevalence of asthma. How would you
proceed to validate and/or intervene
therapeutically based on your conclusions? Ast
hma is an integrated tissue response involving
innate and adaptive cell cross-talk. Delineate
the relevant cell types, the pathways believed to
drive the tissue pathology, and identify shared
nodes of intervention designed to disrupt the
cytokine/cellular network in order to restore
homeostasis. Consider possible off-target
side-effects, even in other tissues.