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Naïve, effector and memory
CD8 T-cells in old age
Beatrix Grubeck-Loebenstein
Institute for Biomedical Aging Research
of the Austrian Academy of Sciences
Human post-thymic CD8+ T cell differentiation
Antigen-experienced cells
Non-primed cells
Naive
Central-Memory
Effector-Memory
Antigen
Phenotype
CD45RA+
CD62L+ / CCR7+
CD28+ / CD27+
IL-6R+ / IL-7R+
Effector
Repeated
antigenic
stimulation/
cytokines
CD45RO+
CD62L+ / CCR7+
CD28+ / CD27+
IL-6R+ / IL-7R+
CD45RO+
CD62L- / CCR7CD28+ / CD27+
IL-6R- / IL-7R+
CD45RA+
CD62L- / CCR7CD28- / CD27IL-6R- / IL-7R-
Depletion of naïve and accumulation of
effector CD8+ T cells in old age
Peripheral
blood
Young
Bone
marrow
Lymph node tissue
17
71
22
73
1
11
1
4
100
80
60
%
40
34
13
33
18
5
48
12
37
20
0
young
CD28
Elderly
CD45RA
Lazuardi et al., Immunology (2005); Weinberger et al., Hum Immunol (2007)
old
The size of CD8+ T cell subsets
changes with age
Do certain conditions accelerate
age related changes in the T cell pool?
 Latent cytomegalovirus infection
 Thymectomy in early life
Latent CMV infection accelerates the depletion of
naïve and the accumulation of effector CD8+ T cells
CD45RA
Almanzar et al., J Virol (2005)
Human immunosenescence: Is it infectious?
Pawelec G. et al., Immunol Rev (2005)
The immunological burden of human cytomegalovirus infection
Khan N. , Arch Immunol Ther Exp (Warsz) (2007)
Ageing and life-long maintenance of T-cell subsets in the face of
latent persistent infections
Nikolich-Zugich J., Nat Rev Immunol (2008)
The immune system in extreme longevity
Sansoni P., Exp Gerontol (2008)
Cytomegalovirus and human immunosenescence
Pawelec G. et al., Rev Med Virol (2009)
CD8+ subset distribution in young adults
thymectomized during early childhood
Sauce et al, J. Clin. Invest. (2009, in press)
TRECs depend on chronological age
as well as on the time post thymectomy
in persons thymectomized during early childhood
Prelog et al, Clin. Immunol. (2009)
Latent infection with cytomegalovirus
and thymectomy in early life
accelerate age-related changes
in the CD8+ T cell pool
Do these changes represent a clinical
problem?
IL-2
75
% IL-2+ cells / CD8+ T cells
GZMB
CD45 RA+
CD28-
50
CD45RO+
CD28-
25
CD45RA+
CD28+
CD45RO+
CD28+
0
75
CD45RA+
CD28+
CD45RO+
CD28+
50
CD45RO+
CD28CD45 RA+
CD28-
25
0
IFN-
% IFN-+ cells / CD8+ T cells
% GZMB+ cells / CD8+ T cells
CD28- T cells are proinflammatory and cytotoxic
75
50
25
0
CD45RO+
CD28-
CD45RA+
CD28+
CD45RO+
CD28+
CD45 RA+
CD28-
Decreased expression of CD8chain and of CD5 during CD8+ T cell differentiation
CD45RA+
CD28+
CD45RO+
CD28+
CD45RO+
CD28–
CD45RA+
CD28–
TCR
5000
2.935
2.597
2.301
2.825
4000
3000
2000
1000
0
CD8
6000
4.347
4.028
3.314
2.813
-16%
4000
2000
0
CD8
10000
12.596
8.080
3.703
-59%
3.197
5000
0
20000
20.698
14.503
CD5
8.326
-55%
15000
10000
5000
–
+
FSC
CD
4
CD 5RA
28 +
0
CD
4
CD 5RA
28 +
25.246
miRNAs are potent post-transcriptional regulators
miRNA-expression during CD8+ T cell
differentiation: CD28+ vs. CD28- T cells
LNA miRNA array (Exigon)
miRNA qPCR
(intensity normalized)
(GAPDH normalized)
n=8
miR-17- 92 targets:
CDKN1A (p21)
CDKN1B (p27)
RB1, Rbl1, Rbl2
PTEN
Bim
miR-17- 92 downregulation during CD8+
T cell differentiation may be a mediator of
replicative exhaustion and/or apoptosis
CD8+CD28- T cells are proinflammatory,
can prevent the expansion of other
specificities and have a decreased
expression of important regulatory
molecules such as the CD8chain,
CD5 and the miR 17- 92 cluster.
Are they dispensable?
Is the clonotypic composition of
CD28+ and CD28- CD8+ T cells different ?
Experimental model
CMV-Pentamer
ex vivo
2.0%
day 14
purified
74.6%
99.4%
FSC
1) Isolation of CD8+ T cells
2) Isolation of CD28+ and
CD28- T cells
1) Expansion of CMV
NLV-specific T cells
(IL-2, peptide,
autologous feeder
cells)
1) Purification of CMV
NLV-specific
T cells with CMVpentamer and
MACS technology
1) spectratyping
2) CDR3 cloning and
sequencing
Weinberger, Immunol Letters 2009 (Epub ahead of print)
Identical TCR-clonotypes in CD28+
and CD28- T cells
Weinberger, Immunol Letters (2009, Epub ahead of print)
Identical clonotypes are present in
CD28+ and CD28- CD8+ T cells
CD8+ CD28- T cells are dispensable
Is there a way to assure the survival of
other more valuable T cell subsets?
Martina Prelog
Pediatric Department, Innsbruck University Medical School
Victor Appay, Delphine Sauce
INSERM U945, Avenir Group, Paris
Johannes Grillari
University of Natural Resources and Applied Life Sciences, Vienna
Frank Madeo
Institute of Molecular Biosciences, University Graz
National Research Network (S9308-B05), Austrian Science Fund
Network of Excellence LifeSpan (EU-FP6 036894)
Beatrix Grubeck-Loebenstein
Birgit Weinberger
Brigitte Jenewein
Dietmar
Herndler-Brandstetter
Katja Landgraf
Michael Keller
Daniela Weiskopf
Kathrin Welzl
Petra Schmid
Stefan Brunner
Barbara Luhan