A model of human cytokine regulation based on transfection of gamma interferon gene fragments directly into isolated peripheral blood T lymphocytes.
An approach has been optimized permitting measurement of human cytokine reporter gene expression after transient transfection directly into purified human peripheral blood T lymphocytes. Comparing the expression of interleukin 2 (IL-2) CAT with a series of specially engineered gamma interferon (IFN-gamma) constructs, a fundamental difference in the molecular mechanisms regulating these two cytokines has been suggested. A potent, tissue-specific, constitutive-acting positive regulatory element was located between sequences -215 and -53 in the human IFN-gamma gene. Deletion analyses suggested that sequences slightly upstream, between positions -251 to -215, exerted a powerful dominant suppressive influence over that positive element. Negative elements appear to play a major role in controlling the regulation of human IFN-gamma gene expression. We thus propose a model of cytokine gene regulation in which selective derepression may be an important fundamental mechanism of induction and/or positive modulation.
Chrivia
J C
JC
Howard Hughes Medical Institute, Baylor College of Medicine, Houston, Texas 77030.
Wedrychowicz
T
T
Young
H A
HA
Hardy
K J
KJ
D001483:Base Sequence; D002478:Cells, Cultured; D003001:Cloning, Molecular; D003850:Deoxyribonuclease I; D005796:Genes; D006801:Humans; D007371:Interferon-gamma / Q000235:genetics*; D008969:Molecular Sequence Data; D009710:Nucleotide Mapping; D010957:Plasmids; D015183:Restriction Mapping; D013601:T-Lymphocytes / Q000276:immunology*; D014162:Transfection
D007371:Interferon-gamma; D003850:Deoxyribonuclease I