Selective induction of interleukin-6 in mouse microglia by granulocyte-macrophage colony-stimulating factor.
Astrocytes produce granulocyte/macrophage colony-stimulating factor (GM-CSF) and support the survival and proliferation of microglia. To study the functions of GM-CSF in the central nervous system (CNS), we examined the effects of GM-CSF on cytokine production by glial cells. GM-CSF induced interleukin-6 (IL-6) production by microglia, but not by astrocytes, in a dose-dependent manner as assessed by bioassay and the detection of IL-6 mRNA by reverse transcriptase-polymerase chain reaction (RT-PCR) analysis. GM-CSF did not induce tumor necrosis factor (TNF) alpha or IL-1 in microglia and astrocytes, whereas lipopolysaccharide induced all these cytokines. The induction of IL-6 by GM-CSF in microglia was completely inhibited by antibodies to GM-CSF. Neither IL-3 nor macrophage-CSF (M-CSF) induced IL-6 production in microglia. Given that IL-1 and TNF alpha, monokines derived from microglia, induce IL-6 production in astrocytes, but not in microglia, results indicate that astrocytes and microglia may mutually regulate IL-6 production by different cytokines.
Suzumura
A
A
Department of Neurology, School of Medicine Fujita Health University, Aichi, Japan.
Sawada
M
M
Marunouchi
T
T
D000818:Animals; D001253:Astrocytes / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000494:pharmacology*; D015850:Interleukin-6 / Q000096:biosynthesis*; D051379:Mice; D008815:Mice, Inbred Strains; D017628:Microglia / Q000187:drug effects*; D013997:Time Factors
D015850:Interleukin-6; D016178:Granulocyte-Macrophage Colony-Stimulating Factor