Activation of the interleukin-10 gene in the human T lymphoma line HuT 78: identification and characterization of NF-kappa B binding sites in the regulatory region of the interleukin-10 gene.
Interleukin-10 (IL-10) is a pleiotropic cytokine which has potent inhibitory effects on macrophages and T cells, and contributes to the regulation of proliferation and differentiation of B cells. Resting HuT 78, a T-cell line derived from a Sezary lymphoma, produced significant amounts of IL-10 compared with another T-cell line, Jurkat. To elucidate the mechanisms by which the IL-10 is expressed, we have analyzed their activity in human T-cell lines. We report here evidence that members of the family of transcription factors nuclear factor-kappa B (NF-kappa B)/Rel can specifically recognize 3 identical sequences located in the 5'-regulatory region of IL-10 gene in resting HuT 78 cells, whereas Jurkat cells expressed high levels of NF-kappa B consisting of p65 and p50 only upon activation with tumor necrosis factor-alpha (TNF-alpha). In HuT 78 cells, p50 was the major component in the NF-kappa B complexes. Exogenous TNF-alpha and the monoclonal antibody to TNF-alpha did not affect IL-10 production and constitutive NF-kappa B binding levels in HuT 78 cells. This study is the first demonstration of a role for NF-kappa B in the IL-10 gene expression, and suggests that its expression does not require TNF-alpha. These novel findings may account for the specific IL-10 gene expression in T cells.
Mori
N
N
Division of Hematology/Oncology, UCLA School of Medicine, USA. n-mori@net.nagasaki-u.ac.jp
Prager
D
D
D000911:Antibodies, Monoclonal / Q000494:pharmacology; D001483:Base Sequence; D004247:DNA / Q000378:metabolism; D004797:Enzyme-Linked Immunosorbent Assay; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D016753:Interleukin-10 / Q000235:genetics* / Q000378:metabolism; D019169:Jurkat Cells; D016399:Lymphoma, T-Cell / Q000235:genetics* / Q000378:metabolism; D016328:NF-kappa B / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000032:analysis; D012045:Regulatory Sequences, Nucleic Acid; D012751:Sezary Syndrome / Q000378:metabolism; D014407:Tumor Cells, Cultured; D014409:Tumor Necrosis Factor-alpha / Q000276:immunology / Q000494:pharmacology
D000911:Antibodies, Monoclonal; D016328:NF-kappa B; D012333:RNA, Messenger; D014409:Tumor Necrosis Factor-alpha; D016753:Interleukin-10; D004247:DNA