title: HTLV-1 cell lines differ in constitutively activated signaling pathways that can be altered by cytokine exposure.
abstract: Examination of signaling pathways used by HTLV-1-infected rabbit cell lines revealed differences between one, RH/K30, that mediates asymptomatic infection and another, RH/K34, that causes lethal experimental leukemia. Both lines are IL-2 independent; RH/K30 produces IL-4 while RH/K34 produces IL-10. Examination of the Jak/STAT (Janus kinase/signal transducer and activator of transcription) activation of the lines revealed constitutive phosphorylation of Jak1 in both STAT6 phosphorylation, not previously reported for HTLV-1 cells, was observed in RH/K30; STAT1 and STAT3 were phosphorylated in RH/K34. Treatment with cytokines altered the activation of the STAT proteins: IL-2 induced STAT5 phosphorylation in both lines. Supernatant from RH/K34 or IL-10 induced STAT3 phosphorylation in RH/K30 cells. Supernatant from RH/K30 or IL-4 induced STAT6 phosphorylation in RH/K34 cells, which could be reversed with a Jak kinase inhibitor--AG-490.
authors.affiliation: Molecular and Cellular Immunogenetics Section, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA. wliang@niaid.nih.gov
authors.forename: W
authors.initials: W
authors.lastname: Liang
authors.forename: B
authors.initials: B
authors.lastname: Hague
authors.forename: T
authors.initials: T
authors.lastname: Zhao
authors.forename: T J
authors.initials: TJ
authors.lastname: Kindt
mesh_terms: D000818:Animals; D002460:Cell Line; D004268:DNA-Binding Proteins / Q000276:immunology*; D004195:Disease Models, Animal; D004791:Enzyme Inhibitors / Q000494:pharmacology; D015870:Gene Expression; D015490:HTLV-I Infections / Q000276:immunology*; D015368:Human T-lymphotropic virus 1 / Q000276:immunology*; D006801:Humans; D016753:Interleukin-10 / Q000235:genetics / Q000276:immunology*; D007376:Interleukin-2 / Q000494:pharmacology; D015847:Interleukin-4 / Q000235:genetics / Q000276:immunology*; D053613:Janus Kinase 1; D008894:Milk Proteins; D010766:Phosphorylation; D011505:Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors / Q000276:immunology*; D011817:Rabbits; D050794:STAT1 Transcription Factor; D050796:STAT3 Transcription Factor; D050799:STAT5 Transcription Factor; D050800:STAT6 Transcription Factor; D015398:Signal Transduction / Q000276:immunology*; D015534:Trans-Activators / Q000276:immunology*; D014407:Tumor Cells, Cultured; D020032:Tyrphostins / Q000494:pharmacology
chemical_list: D004268:DNA-Binding Proteins; D004791:Enzyme Inhibitors; D007376:Interleukin-2; D008894:Milk Proteins; D050794:STAT1 Transcription Factor; C494079:STAT1 protein, human; D050796:STAT3 Transcription Factor; C494086:STAT3 protein, human; D050799:STAT5 Transcription Factor; D050800:STAT6 Transcription Factor; C494101:STAT6 protein, human; D015534:Trans-Activators; D020032:Tyrphostins; C095512:alpha-cyano-(3,4-dihydroxy)-N-benzylcinnamide; D016753:Interleukin-10; D015847:Interleukin-4; D011505:Protein-Tyrosine Kinases; C507904:JAK1 protein, human; D053613:Janus Kinase 1