Title: Asthmatic Phenotypes in the PhysGen Consomic Rats
1Asthmatic Phenotypes in the PhysGen Consomic
Rats UW-MCW Collaboration Project Update
L.A. Rosenthal, R.L. Sorkness, and R.F. Lemanske,
Jr.
Morris Institute for Respiratory Research
2Genetic Factors
Environmental Factors
Atopy (Cytokine Dysregulation)
Respiratory Viruses Allergens
AGE
Asthma Phenotype
3Post-bronchiolitis Asthma-like Phenotype
aerosolized parainfluenza type 1 (Sendai) virus
weanling rats (3-4 weeks old)
Fischer 344 (F344)
Brown Norway (BN)
low IgE producer nonatopic (Th1)
high IgE producer atopic (Th2)
8-10 weeks postinfection
Normal Airways
Abnormal Airways
- episodic, reversible airway obstruction
- chronic airway inflammation
- airway hyperresponsiveness to methacholine
- airway wall remodeling
Model developed in collaboration with W.L.
Castleman (U. of Florida)
4Genetic Factor
Environmental Factor
AGE
Rat Strain
Sendai Virus
Asthmatic Phenotype
5Development of the Post-bronchiolitis Asthma-like
Phenotype in Brown Norway Rats Host Response
(Genetic Factor) to Sendai Virus (Environmental
Factor) During Early Life (Developmental
Factor) Drives Process
6Acute Phase
Chronic Phase
BN and F344 Bronchiolitis
BN YES F344 NO
Dysregulation of innate immune response?
d6-8
gt Week 4
Sendai Virus Infection
Virus shedding
Abnormal resolution of acute inflammatory changes?
- Development of asthma-like phenotype
- episodic, reversible airway obstruction
- chronic airway inflammation
- airway hyperresponsiveness
- airway wall remodeling
d2
Viral replication
d10-14
Resolution of acute inflammatory changes
7Development of Asthma-like Phenotype Importance
of IFN-g During Acute Phase
- IFN-g in bronchoalveolar lavage fluid during
acute Sendai virus infection in weanling rats
F344 gt BN - Aerosolized IFN-g prevents the development of
post-bronchiolitis chronic airway dysfunction in
BN rats.
8Post-bronchiolitis Asthma-like Phenotype
aerosolized parainfluenza type 1 (Sendai) virus
IFN-g
weanling rats (3-4 weeks old)
Fischer 344 (F344)
Brown Norway (BN)
low IgE producer nonatopic (Th1)
high IgE producer atopic (Th2)
8-10 weeks postinfection
Normal Airways
Normal Airways
Sorkness et al. 1999. AJRCCM 160705
9PhysGen Consomic Rats
- Parental strains for consomic rats
- Dahl salt sensitive (SS hypertension model)
- Fawn hooded hypertensive (FHH hypertension and
end-stage renal disease model) - Brown Norway (BN control strain normotensive)
- Useful for studying the role of genetic factors
in susceptibility/resistance to the development
of the post-bronchiolitis asthma-like phenotype?
10Balance Between Th1- and Th2-type Cytokines
Th2
Th1
Th1
Th2
BN
F344
SS?
FHH?
atopic
non-atopic
Th1-type IFN-g, IL-12 Th2-type IL-4, IL-5,
IL-13
11Are the Immune Responses of SS and FHH Rats
Th1-biased Like Those of F344 Rats?
12Screening Assay for Th1- and Th2-type Cytokine
Production by Spleen Cells
Con A
24 h
Measure Cytokine Levels in Supernatant Fluids
13IFN-g Production by Con A-stimulated Spleen Cells
14IL-4 Production by Con A-stimulated Spleen Cells
15IFN-g/IL-4 Ratio for Con A-stimulated Spleen Cells
16IL-13 Production by Con A-stimulated Spleen Cells
17IFN-g/IL-13 Ratio for Con A-stimulated Spleen
Cells
18Balance Between Th1- and Th2-type Cytokines
Th2
Th1
Th1
Th2
BN
F344
SS
FHH
atopic
non-atopic
Th1-type IFN-g, IL-12 Th2-type IL-4, IL-5,
IL-13
19Are SS Rats, Like F344 Rats, Resistant to the
Development of Post-bronchiolitis Airway
Dysfunction?
20Post-bronchiolitis Airway Dysfunction in BN, but
not SS, Rats
21Therefore, in vitro cytokine data and in vivo
physiology data suggest that the PhysGen consomic
rat strains will be useful tools for studying the
role of genetic factors in susceptibility/resistan
ce to the development of the post-bronchiolitis
asthma-like phenotype.
22Screening of Consomic Rat Strains
- SS.BN13
- SS.BN16
- SS.BN18
- SS.BN9
- SS.BN20
23Screening Assay for Th1- and Th2-type Cytokine
Production by Spleen Cells
Con A
24 h
Measure Cytokine Levels in Supernatant Fluids
24IFN-g Production by Con A-stimulated Spleen Cells
25Th1 and Th2 Cytokine Production
- No strain differences were observed among SS and
these five SS.BN strains with regard to Con
A-stimulated IFN-g production or IL-4 or IL-13
production (not shown) .
26Chr. 20 Major Histocompatibility Complex
- SS.BN20
- Histocompatible with BN?
- Histoincompatible with SS?
27Two-way Mixed Lymphocyte Cultures
72 h
Strain A
Strain B
Measure IL-2 and IFN-g Levels in Supernatant
Fluids
28IL-2 Production in 2-way Mixed Lymphocyte
Cultures BN and SS.BN20 Splenocytes are
Histocompatible
BN BN
F344 F344
SS.BN20 SS.BN20
BN F344
F344 SS.BN20
BN SS.BN20
29IL-2 Production in 2-way Mixed Lymphocyte
Cultures SS and SS.BN20 Splenocytes are
Histoincompatible
BN BN
SS SS
SS.BN20 SS.BN20
BN SS
SS SS.BN20
BN SS.BN20
30IFN-g Production in 2-way Mixed Lymphocyte
Cultures SS and SS.BN20 Splenocytes are
Histoincompatible
BN BN
SS SS
SS.BN20 SS.BN20
BN SS
SS SS.BN20
BN SS.BN20
31Potential Uses of the Histocompatible SS.BN20
Strain for Studies in BN Rats
- in vitro
- cell mixing studies
- in vivo
- adoptive cell transfer studies
- organ transplant studies
32PhysGen Consomic Rat Development Timeline
- SS.BN12
- FHH.BN1 (IL-4Ra)
- SS.BN6 (Immunoglobulin)
- SS.BN7 (IFN-g)
- SS.BN8
- Fischer CDF(F-344)CrlBR
- BN/SsNHsd/Mcw
http//pga.mcw.edu
33Future Directions
- Continue screening spleens from adult consomic
rats. - PhysGen consomic rat strains to be distributed
- through Charles River Laboratories.
- Availability of weanling consomic rats will
significantly increase options with regard to
screening. - Level of characterization of weanlings from each
consomic strain? Resources that will inform
these decisions include - Rat Genome Database Rat Genome Sequencing
Project - Virtual Comparative Maps
- MCW-TIGR microarray expression profiling of rat
- consomic panels (lung)
34Funded by NIH/NIAID Asthma and Allergic Disease
Research Center Grant AI050500