Constitutive STAT3 Activation in Intestinal T Cells from Patients with Crohn's Disease*

Via cytoplasmic signal transduction pathways, cytokines induce a variety of biological responses and modulate the outcome of inflammatory diseases and malignancies. Crohn's disease is a chronic inflammatory bowel disease of unknown etiology. Perturbation of the intestinal cytokine homeostasis is believed to play a pivotal role, but the pathogenesis of Crohn's disease is not fully understood. Here, we study intestinal T cells from Crohn's disease and healthy volunteers. We show that STAT3 and STAT4 are constitutively activated in Crohn's patients but not in healthy volunteers. The activation is specific, because other STAT proteins are not constitutively activated. Furthermore, the STAT3 regulated protein, SOCS3, is also constitutively expressed in Crohn's patients but not in healthy volunteers. Taken together, these data provide evidence of abnormal STAT/SOCS signaling in Crohn's disease. This aberrant activation, so far noted only in malignant cells, establish a new critical approach for better understanding the immunopathogenesis of Crohn's disease.

[1]  Qian Zhang,et al.  Multilevel Dysregulation of STAT3 Activation in Anaplastic Lymphoma Kinase-Positive T/Null-Cell Lymphoma1 , 2002, The Journal of Immunology.

[2]  Hua Yu,et al.  Constitutive activation of Stat3 by the Src and JAK tyrosine kinases participates in growth regulation of human breast carcinoma cells , 2001, Oncogene.

[3]  S. Akira,et al.  Cis3/Socs3/Ssi3 Plays a Negative Regulatory Role in Stat3 Activation and Intestinal Inflammation , 2001, The Journal of experimental medicine.

[4]  M. Wasik,et al.  STAT3-mediated constitutive expression of SOCS-3 in cutaneous T-cell lymphoma. , 2001, Blood.

[5]  C. Horvath,et al.  STAT proteins and transcriptional responses to extracellular signals. , 2000, Trends in biochemical sciences.

[6]  T. Hirano,et al.  Roles of STAT3 in mediating the cell growth, differentiation and survival signals relayed through the IL-6 family of cytokine receptors , 2000, Oncogene.

[7]  J. Grandis,et al.  STAT signaling in head and neck cancer , 2000, Oncogene.

[8]  C. Schindler Cytokines and JAK-STAT signaling. , 1999, Experimental cell research.

[9]  M. Neurath,et al.  Cutting edge: chronic intestinal inflammation in STAT-4 transgenic mice: characterization of disease and adoptive transfer by TNF- plus IFN-gamma-producing CD4+ T cells that respond to bacterial antigens. , 1999, Journal of immunology.

[10]  D. Hilton,et al.  Negative regulation of the JAK/STAT pathway , 1999, BioEssays : news and reviews in molecular, cellular and developmental biology.

[11]  Y. Matsuzawa,et al.  STAT3 mediates the survival signal in oncogenic ras‐transfected intestinal epithelial cells , 1998, International journal of cancer.

[12]  C. Fiocchi Inflammatory bowel disease: etiology and pathogenesis. , 1998, Gastroenterology.

[13]  Samir A. Shah,et al.  T Cell–mediated Pathology in Two Models of Experimental Colitis Depends Predominantly on the Interleukin 12/Signal Transducer and Activator of Transcription (Stat)-4 Pathway, but Is Not Conditional on Interferon γ Expression by T Cells , 1998, The Journal of experimental medicine.

[14]  J. Darnell STATs and gene regulation. , 1997, Science.

[15]  Warren S. Alexander,et al.  A family of cytokine-inducible inhibitors of signalling , 1997, Nature.

[16]  S. Akira,et al.  Structure and function of a new STAT-induced STAT inhibitor , 1997, Nature.

[17]  T. Mustelin,et al.  Constitutive activation of a slowly migrating isoform of Stat3 in mycosis fungoides: tyrphostin AG490 inhibits Stat3 activation and growth of mycosis fungoides tumor cell lines. , 1997, Proceedings of the National Academy of Sciences of the United States of America.

[18]  G. Morrone,et al.  Interleukin 12 is expressed and actively released by Crohn's disease intestinal lamina propria mononuclear cells. , 1997, Gastroenterology.

[19]  Tom Maniatis,et al.  Regulation of Interferon-γ-Activated STAT1 by the Ubiquitin-Proteasome Pathway , 1996, Science.

[20]  M. Neurath,et al.  Disparate CD4+ lamina propria (LP) lymphokine secretion profiles in inflammatory bowel disease. Crohn's disease LP cells manifest increased secretion of IFN-gamma, whereas ulcerative colitis LP cells manifest increased secretion of IL-5. , 1996, Journal of immunology.

[21]  B. Groner,et al.  STAT-related transcription factors are constitutively activated in peripheral blood cells from acute leukemia patients , 1996 .

[22]  W. Leonard,et al.  Constitutively activated Jak-STAT pathway in T cells transformed with HTLV-I. , 1995, Science.

[23]  W. Paul,et al.  Cloning of murine Stat6 and human Stat6, Stat proteins that are tyrosine phosphorylated in responses to IL-4 and IL-3 but are not required for mitogenesis , 1995, Molecular and cellular biology.

[24]  W. Leonard,et al.  Jaks and STATs: biological implications. , 1998, Annual review of immunology.

[25]  K. Bendtzen,et al.  MHC class II molecules regulate growth in human T cells. , 1994, Experimental and clinical immunogenetics.