Mechanism of interferon-gamma down-regulation of the interleukin 4-induced CD23/Fc epsilon RII expression in human B cells: post-transcriptional modulation by interferon-gamma.
It has been reported that the interleukin 4 (IL-4) specific induction of cell surface CD23 (Fc epsilon RII) is down-regulated by interferon-gamma (IFN-gamma) in monocytes and B cells. However, the molecular level at which the inhibition occurs seems to vary depending on the cell types. In normal human B cells, IFN-gamma inhibits the IL-4 induced de novo synthesis of CD23 at the level of gene expression. Analysis of inhibition kinetics suggested a rapid signal transmission by IFN-gamma. Yet the inhibitory action of IFN-gamma on CD23 mRNA accumulation appeared as a secondary response requiring a new protein synthesis. Through nuclear run-on transcription and mRNA stability studies, we further demonstrate that the IL-4 induced CD23 gene expression is down-regulated by IFN-gamma mainly at post-transcriptional levels by decreasing mRNA stability.
Lee
C E
CE
Immunology Research Laboratory, Genetic Engineering Research Institute, KIST, Taedok Science Town, Taejon, Korea.
Yoon
S R
SR
Pyun
K H
KH
D001402:B-Lymphocytes / Q000276:immunology*; D015536:Down-Regulation; D005786:Gene Expression Regulation / Q000187:drug effects*; D006801:Humans; D007371:Interferon-gamma / Q000494:pharmacology*; D015847:Interleukin-4 / Q000494:pharmacology*; D012323:RNA Processing, Post-Transcriptional; D012333:RNA, Messenger / Q000032:analysis / Q000187:drug effects; D017455:Receptors, IgE / Q000096:biosynthesis* / Q000235:genetics
D012333:RNA, Messenger; D017455:Receptors, IgE; D015847:Interleukin-4; D007371:Interferon-gamma