The effect of interleukin-1beta (IL-1beta) and tumor necrosis factor-alpha (TNF-alpha) on granulocyte macrophage-colony stimulating factor (GM-CSF) production by neuronal precursor cells.
OBJECTIVE
To determine whether granulocyte macrophage-colony stimulating factor (GM-CSF) production by neuronal precursor (NT2) cells can be regulated by IL-1beta and TNF-alpha.


BACKGROUND
We have previously demonstrated GM-CSF expression by neurons of the developing human brain, as well as by NT2 cells. IL-1beta and TNF-alpha upregulate GM-CSF production in glial cells, but GM-CSF regulation in neurons is as yet undefined. We hypothesized that IL-1beta and TNF-alpha would increase GM-CSF mRNA and protein production in NT2 cells.


METHODS
The effect of IL-1beta and TNF-alpha on GM-CSF production was assessed by dose response (0 to 2,000 U/ml), and time course (0 to 48 hours incubation) experiments. GM-CSF mRNA and protein production were assessed by quantitative RT-PCR and by ELISA. The effect of these cytokines on cell turnover was determined by BrdU incorporation.


RESULTS
IL-1beta increased GM-CSF mRNA and protein expression by NT2 cells. This effect was time and dose dependent, and the effective dose ranging from (20-200 U/ml). TNF-alpha increased GM-CSF mRNA expression to a lesser extent than did IL-1beta (maximal stimulation at 200 U/ml), and a minimal increase in net protein accumulation was noted. Neither cytokine increased NT2 cell turnover.


CONCLUSIONS
IL-1beta and TNF-alpha both increase GM-CSF mRNA expression by NT2 cells, but only IL-1beta increases net GM-CSF protein accumulation.
Dame
J Benjamin
JB
Department of Pediatrics, University of Florida College of Medicine, Gainesville, FL 32610, USA. john.dame@hsc.utah.edu
Chegini
Nasser
N
Christensen
Robert D
RD
Juul
Sandra E
SE
D002460:Cell Line; D002478:Cells, Cultured; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000096:biosynthesis* / Q000235:genetics; D006801:Humans; D007375:Interleukin-1 / Q000494:pharmacology*; D009474:Neurons / Q000187:drug effects* / Q000378:metabolism; D012333:RNA, Messenger / Q000096:biosynthesis; D013234:Stem Cells / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology*
D007375:Interleukin-1; D012333:RNA, Messenger; D014409:Tumor Necrosis Factor-alpha; D016178:Granulocyte-Macrophage Colony-Stimulating Factor