The four major subsets of CD4 T cells

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The four major subsets of CD4 T cells
Tolerance Immunity
Defense against intracellular viruses and
bacteria Autoimmunity
STAT1/4
IL-2 IFN-?
Th1
(TNF-a)
T-bet
Defense against extracellular parasites Allergy
(IL-2) (IL-6) (IL-10) (IL-9)
(IL-25)
(TNF-a)
IL-4 IL-5 IL-13
STAT5
STAT5/6
Th2
nTreg
Foxp3
GATA3
Defense against extracellular pathogens (fungi,
bacteria) Autoimmunity
STAT3
IL-17 IL-22
Th17
(IL-21) (IL-26)
ROR?t
Master Regulators
Angelika Schmidt
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The growing family of CD4 T cell subsets
Tolerance
Immunity
Tfr
Th1
Th3
Th9
nTreg
Th2
Tfh
Th22
Tr1
Th17
Tr35
Angelika Schmidt
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T cells are activated by T cell receptor (TCR)
signaling
A simplified view of TCR signaling cascades
Adapted from Schmidt et al., Frontiers in
Immunology, 2012
Angelika Schmidt
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Regulatory T cells (Tregs) suppress other immune
cells
Prevention of autoimmunity, allergies,
excessive immune reactions
Prevention of anti-tumor immunity
Angelika Schmidt
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Tregs suppress T cell activation by different
mechanisms
Cytokine consumption and cell death induction
Inhibitory cytokines
Treg
Suppressive metabolites
CD4CD25 Foxp3
Indirect suppression through DC inhibition
cAMP
Ca2 NFAT NF-?B
Suppression of TCR signaling pathways
ICER Ikaros
Transcriptional repressors
Tcon
CD4CD25Foxp3
Adapted from Schmidt et al., Frontiers in
Immunology, 2012
Angelika Schmidt