TY - JOUR
T1 - Early immune response and regulation of IL-2 receptor subunits
AU - Hughes-Fulford, Millie
AU - Sugano, Eiko
AU - Schopper, Thomas
AU - Li, Chai-Fei
AU - Boonyaratanakornkit, J. B.
AU - Cogoli, Augusto
PY - 2005/9/1
Y1 - 2005/9/1
N2 - Affymetrix oligonucleotide arrays were used to monitor expression of 8796 genes and probe sets in activated T-cells; analysis revealed that 217 genes were significantly upregulated within 4 h. Induced genes included transcription factors, cytokines and their receptor genes. Analysis by semi-quantitative RT-PCR confirmed the significant induction of IL-2, IL-2Rγ and IL-2Rα. Forty-eight of the 217 induced genes are known to or predicted to be regulated by a CRE promoter/enhancer. We found that T-cell activation caused a significant increase in CREB phosphorylation furthermore, inhibition of the PKC pathway by GF109203 reduced CREB activation by 50% and inhibition of the PKA pathway caused a total block of CREB phosphorylation and significantly reduced IFNγ, IL-2 and IL-2Rα gene expression by approximately 40% (p<0.001). PKCθ plays a major role in T-cell activation: inhibition of PKC significantly reduced the expression of IFNγ, IL-2 and IL-2Rα. Since PKC blocked activation of CREB, we studied potential cross-talk between the PKC and the PKA/MAPK pathways, PMA-stimulated Jurkat cells were studied with specific signal pathway inhibitors. Extracellular signal-regulated kinase-2 (ERK2) pathway was found to be significantly activated greater than seven-fold within 30 min; however, there was little activation of ERK-1 and no activation of JNK or p38 MAPK. Inhibition of the PKA pathway, but not the PKC pathway, resulted in inhibition of ERK1/2 activation at all time points, inhibition of MEK1 and 2 significantly blocked expression of IL-2 and IL-2Rα. Gene expression of IL-2Rα and IFNγ was dependent on PKA in S49 wt cells but not in kin- mutants. Using gel shift analysis, we found that forskolin activation of T-cells resulted in activation of AP1 sites; this increase in nuclear extract AP1 was significantly blocked by MEK1 inhibitor U0126. Taken together, these results suggest that the PKA in addition to PKC and MAPK pathways plays a role in early T-cell activation and induction of IL-2, IL-2Rα and IFNγ gene expression.
AB - Affymetrix oligonucleotide arrays were used to monitor expression of 8796 genes and probe sets in activated T-cells; analysis revealed that 217 genes were significantly upregulated within 4 h. Induced genes included transcription factors, cytokines and their receptor genes. Analysis by semi-quantitative RT-PCR confirmed the significant induction of IL-2, IL-2Rγ and IL-2Rα. Forty-eight of the 217 induced genes are known to or predicted to be regulated by a CRE promoter/enhancer. We found that T-cell activation caused a significant increase in CREB phosphorylation furthermore, inhibition of the PKC pathway by GF109203 reduced CREB activation by 50% and inhibition of the PKA pathway caused a total block of CREB phosphorylation and significantly reduced IFNγ, IL-2 and IL-2Rα gene expression by approximately 40% (p<0.001). PKCθ plays a major role in T-cell activation: inhibition of PKC significantly reduced the expression of IFNγ, IL-2 and IL-2Rα. Since PKC blocked activation of CREB, we studied potential cross-talk between the PKC and the PKA/MAPK pathways, PMA-stimulated Jurkat cells were studied with specific signal pathway inhibitors. Extracellular signal-regulated kinase-2 (ERK2) pathway was found to be significantly activated greater than seven-fold within 30 min; however, there was little activation of ERK-1 and no activation of JNK or p38 MAPK. Inhibition of the PKA pathway, but not the PKC pathway, resulted in inhibition of ERK1/2 activation at all time points, inhibition of MEK1 and 2 significantly blocked expression of IL-2 and IL-2Rα. Gene expression of IL-2Rα and IFNγ was dependent on PKA in S49 wt cells but not in kin- mutants. Using gel shift analysis, we found that forskolin activation of T-cells resulted in activation of AP1 sites; this increase in nuclear extract AP1 was significantly blocked by MEK1 inhibitor U0126. Taken together, these results suggest that the PKA in addition to PKC and MAPK pathways plays a role in early T-cell activation and induction of IL-2, IL-2Rα and IFNγ gene expression.
KW - IL-2 receptor
KW - IL-2 receptor subunits
KW - Immune response
KW - Interleukin-2
KW - Protein kinase A
KW - T-cell activation
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U2 - 10.1016/j.cellsig.2004.12.016
DO - 10.1016/j.cellsig.2004.12.016
M3 - Article
C2 - 15993752
AN - SCOPUS:21644459971
VL - 17
SP - 1111
EP - 1124
JO - Cellular Signalling
JF - Cellular Signalling
SN - 0898-6568
IS - 9
ER -