| First Author | Gomez-Rodriguez J | Year | 2014 |
| Journal | J Exp Med | Volume | 211 |
| Issue | 3 | Pages | 529-43 |
| PubMed ID | 24534190 | Mgi Jnum | J:210475 |
| Mgi Id | MGI:5571235 | Doi | 10.1084/jem.20131459 |
| Citation | Gomez-Rodriguez J, et al. (2014) Itk-mediated integration of T cell receptor and cytokine signaling regulates the balance between Th17 and regulatory T cells. J Exp Med 211(3):529-43 |
| abstractText | A proper balance between Th17 and T regulatory cells (Treg cells) is critical for generating protective immune responses while minimizing autoimmunity. We show that the Tec family kinase Itk (IL2-inducible T cell kinase), a component of T cell receptor (TCR) signaling pathways, influences this balance by regulating cross talk between TCR and cytokine signaling. Under both Th17 and Treg cell differentiation conditions, Itk(-/-) CD4(+) T cells develop higher percentages of functional FoxP3(+) cells, associated with increased sensitivity to IL-2. Itk(-/-) CD4(+) T cells also preferentially develop into Treg cells in vivo. We find that Itk-deficient T cells exhibit reduced TCR-induced phosphorylation of mammalian target of rapamycin (mTOR) targets, accompanied by downstream metabolic alterations. Surprisingly, Itk(-/-) cells also exhibit reduced IL-2-induced mTOR activation, despite increased STAT5 phosphorylation. We demonstrate that in wild-type CD4(+) T cells, TCR stimulation leads to a dose-dependent repression of Pten. However, at low TCR stimulation or in the absence of Itk, Pten is not effectively repressed, thereby uncoupling STAT5 phosphorylation and phosphoinositide-3-kinase (PI3K) pathways. Moreover, Itk-deficient CD4(+) T cells show impaired TCR-mediated induction of Myc and miR-19b, known repressors of Pten. Our results demonstrate that Itk helps orchestrate positive feedback loops integrating multiple T cell signaling pathways, suggesting Itk as a potential target for altering the balance between Th17 and Treg cells. |
