Cell Immunol 2001,
PMID: 11277615
Barna, B P; Mattera, R; Jacobs, B S; Drazba, J; Estes, M E; Prayson, R A; Barnett, G H
Human astrocytes express the interleukin (IL)-4 receptor alpha chain (IL-4R alpha) in vitro and in vivo but mechanisms governing astrocyte IL-4R alpha expression have not been established. We hypothesized that epidermal growth factor (EGF) and IL-4, agents that profoundly affect astrocyte proliferation, might also alter IL-4R alpha expression. Exposure to EGF for 24 h enhanced IL-4R alpha mRNA levels; in contrast, IL-4 yielded no increase. Immunoblotting demonstrated that EGF but not IL-4 increased astrocyte IL-4R alpha protein after 2--4 days of exposure. Similarly, EGF but not IL-4 strongly activated phosphorylation of p42/p44 extracellular regulated kinase isoforms, a reaction blocked by the mitogen-activated protein kinase (MAPK) inhibitor, PD98059. PD98059 also blocked EGF-stimulated DNA synthesis but not IL-4R alpha mRNA levels, while antibody to the EGF receptor (erbB1) blocked both EGF effects. Data suggest that astrocyte IL-4R alpha expression is upregulated by EGF but not by IL-4 in an EGF-receptor-dependent manner and that mechanisms are independent of MAPK activation.
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Text Mining Data
IL-4R alpha → EGF: "
Immunoblotting demonstrated that
EGF but not IL-4
increased astrocyte
IL-4R alpha protein after 2 -- 4 days of exposure
"
IL-4R alpha → IL-4: "
Immunoblotting demonstrated that EGF but not IL-4 increased astrocyte IL-4R alpha protein after 2 -- 4 days of exposure
"
IL-4R alpha → EGF: "
PD98059 also blocked EGF stimulated DNA synthesis but not IL-4R alpha mRNA levels, while antibody to the EGF receptor ( erbB1 ) blocked both EGF effects
"
EGF — MAPK: "
Data suggest that astrocyte IL-4R alpha expression is upregulated by EGF but not by IL-4 in an EGF-receptor dependent manner and that mechanisms are independent of MAPK activation
"
IL-4 — MAPK: "
Data suggest that astrocyte IL-4R alpha expression is upregulated by EGF but not by IL-4 in an EGF-receptor dependent manner and that mechanisms are independent of MAPK activation
"
IL-4R alpha — EGF-receptor: "
Data suggest that astrocyte IL-4R alpha expression is upregulated by EGF but not by IL-4 in an EGF-receptor dependent manner and that mechanisms are independent of MAPK activation
"
Manually curated Databases
No curated data.