Download Genetically Driven n

Immunoregulatory activity
of dietary omega-3
polyunsaturated fatty acids
in T cells
Wooki Kim, Ph.D.
Dept of Food Sci & Biotech, Kyung Hee University
Immunity
 A resistance of an organism against infection or
disease.
 Antigen
 Exogenous: food, pathogen, pollen, etc
 Endogenous: self-peptides, damaged tissues, tumors
 Activation vs Regulation
Hostdefense
Selfimmunity
Chronic Inflammation:
Body Under a Fire
Immune systems
Immune
systems
CD4 T cell
Innate immunity
: Fast, No
memory
Adoptive
immunity
: Slow, Memory
CD4+ T-cells control adaptive immune
system
Zhu et al. Blood. 2008. 112, 1557-69
CD4 T cell: a Control Tower
Th1
Virus, Cancer
Chronic inflammation
Th2
Bacteria, Peptide
Allergy
Again, Balance Matters
Chronic
inflammation
Pathogenesis
Th1
Th2
Activation
Regulation
Factors affecting CD4 T cell function
 Genetic background
 Age, Gender
 Pathogen, Hygienity
 Gut flora
 Habits: Alcohol, Smoking, Exercise
 Diets: Vitamins, Ribonucleotides,
Phytochemical polyphenols, Lipids
n-3 Polyunsaturated Fatty Acids:
Potential Immunoregulator
Fish oil
Corn oil
Old Greenland Story
Disease
Incidence in Greenland
Expected incidence
Diabetes mellitus
1
9
Psoriasis
2
40
Bronchial asthma
1
25
Multiple sclerosis
0
7
Total
4
81
Kromann, N. et al. Acta Med Scand. 1980
Human Clinical Trials
Disease
Number of studies
Rheumatoid arthritis
14
Crohn’s disease
3
Ulcerative colitis
4
Psoriasis
2
Reviewed by Calder, P.C. Lipids. 2001
Hypothesis 1
 Dietary n-3 PUFA inhibit Th1 development in vivo.
CD4 T cell Adoptive Transfer
DO11.10
CD4 T cell
transgenic
mice
OVA
OVA+ CFA
(Th1)
CD4 T cell
n-3 vs n-6
Normal
mice
Flowcytometry
 Cell size
 Granulity
 Surface markers
 Cell count
FO decreased lymphocyte
accumulation
3.0
cell (%)
Donor %
2.5
2.0
*
1.5
1.0
0.5
0.0
CO
n-6
FO
n-3
Zhang et al. J Nutr. 2006. 136: 2391-2398
Cell Trafficking vs Proliferation
Cell Injection
Cell Trafficking vs Proliferation
n-3?
Cell Trafficking vs Proliferation
Cell Injection
Cell Trafficking vs Proliferation
Immunization
Cell Trafficking vs Proliferation
n-3?
Cell Trafficking vs Proliferation
n-3?
n-3?
Cell division analysis by CFSE
CD4 T cell Adoptive Transfer
OVA+ CFA
(Th1)
Normal
mice
FO suppressed Th1 cell division
in vivo
OVA
n-6
No OVA
n-3
CFSE
Zhang et al. J Nutr. 2006. 136: 2391-2398
Summary 1
Dietary fish oil (n-3 PUFA) suppressed Th1 cell division.
Chronic
inflammation
Pathogenesis
Th1
Th2
Activation
Regulation
Question
 What is the molecular mechanisms by which CD4
T cell function is affected by n-3 PUFA?
Proposed Action of n-3 PUFA
Wooki Kim et al. Prosta, Leukotri & Essent Fatty Acids. 2009
Lipid rafts: a putative target of
n-3 PUFA
 Cholesterol/
sphingolipid rich
 Liquid ordered
 Heterogeneity
 Signaling platform
 Small: 5-200 nm
 Highly dynamic
DHA
Fan et al. 2004. J Immunol. 173, 6151-6160
Pike. 2006. J Lipid Res. 47: 1597-1598
TCR proximal signaling
APC
MHC
Ag
TCR/CD3
complex
T-cell
L
A
T
Lck
Jury et al. Sem Cell Dev Biol. 2007. 18: 608-615
TCR proximal signaling
L
A
P
T
L
A
T
PLC
γ1 P
Grb
2
SLP
76
Gads
PLC
γ1
PIP2
F-actin
Lck
PKCθ
P
CARMA1
NF-kB signaling
F-actin
Zap
70
IP3
DAG
Ca2+ signaling
PKCθ
CARMA1
Jury et al. Sem Cell Dev Biol. 2007. 18: 608-615
Hypothesis 2
 n-3 PUFA promote lipid raft formation at the immune
synapse, thereby altering signaling molecule recruitment
and activation in CD4 T-cells
Laurdan: A lipid raft indicator
in living cells
↑ GP
Lipid rafts
↓ GP
Non-raft
Gaus et al, Mol. Memb. Biol. 23. 41-48. 2006
Immunological synapse: a docking station
Magnification 40x
IS
Wooki Kim et al. J. Immunol. 2008.
n-3 PUFA enhance lipid raft formation
at the IS
0.50
GP-value
*
0.40
0.30
n-3
n-6
Immune synapse
Wooki Kim et al. J. Immunol. 2008.
Protein patching at the IS
Magnification 40x
non-patching
CD4+ T-cell
1o anti-LAT
patching
2o anti-IgGAlexa 568
APC
% conjugate with patching = (# cells with patching) / (# cells examined)
Wooki Kim et al. J. Immunol. 2008.
n-3 PUFA suppress relocalization of
signaling proteins at the IS
% Conjugate with patching
80
*
70
60
*
*
50
40
30
20
10
0
PKCθ
CARMA1
LAT
n-6
WT
PLCγ1
F-actin
n-3
fat-1
Wooki Kim et al. J. Immunol. 2008.
Phosphorylated protein
patching at the IS
patching
1o anti-p-PLCγ1
2o anti-IgGAlexa 568
% conjugate with patching = (# cells with patching) / (# cells examined)
Wooki Kim et al. J. Immunol. 2008.
n-3 PUFA suppress PLC1 activation at the IS
*P=0.034
n-6
n-3
Wooki Kim et al. J. Immunol. 2008.
Suppressed Proliferation by n-3 PUFA
n-6
n-3
Wooki Kim et al. J. Immunol. 2008.
n-3 PUFA enhance lipid raft formation to
suppress signaling and proliferation
L
A
T
Lck
P
P
F-actin
P
Grb
2
SLP
76
Gads
PLC
γ1
Zap
70
T-cell
proliferation
PKCθ
CARMA1
Summary
 Balance
 CD4 T cell activation vs regulation.
 Th1 vs Th2 differentiation.
 Hyperactivation of Th1 cells results in chronic inflammatory
disease.
 n-3 PUFA suppress Th1 differentiation.
 n-3 PUFA increase lipid raft formation, thereby suppress T
cell signaling cascade.
Questions & Comments