[Effect of lipopolysacharide on the biological features and growth factor secretion power of U937 cell line].
OBJECTIVE
To investigate the effect of lipopolysacharide (LPS) in different concentrations on the biological features and growth factor secretion power of U937 cell line.


METHODS
In vitro cultured U937 cells were stimulated by 0 (as control), 0.1, 1.0, 10.0, 50.0 and 100 micro g/ml LPS respectively for 24 hours. Thereafter, the cell proliferation ability was determined by MTT method. The cell apoptosis rate was determined by flow cytometry. The changes in the contents of transforming growth factor beta(1) (TGFbeta(1)) and vascular endothelial growth factor (VEGF) of the supernatant of the cell culture were assessed by ELISA.


RESULTS
Apoptosis and TGFbeta(1) secretion could be induced by LPS in dose of 0.1 to 100 micro g/ml when compared with that without LPS challenge (P < 0.05 - 0.01). In detail, LPS in lower dose (0.1, 1.0 and 10.0 micro g/ml) could promote the proliferation of U937 (P < 0.05 - 0.01) but exerted no effect on VEGF secretion. In contrary, LPS in high dose (50 and 100 micro g/ml) could promote VEGF secretion (P < 0.01) but exerted no effects on the proliferation of U937 cells.


CONCLUSIONS
U937 cells could be activated to increase the secretion of TGFbeta(1) by LPS in optimal dose of 0.1 - 10.0 micro g/ml, but the secretion of VEGF could only be promoted by LPS in higher concentration.
Institute of Burn Research, Southwestern Hospital, State Key Laboratory of Trauma, Burns and Combined Injury, The Third Military Medical University, Chongqing 400038, P. R. China.
Jia
J
Ming
Xu-Sheng
XS
Liu
Liang
L
Liu
Hui
H
Xu
Xin-Ze
XZ
Ran
Tian-Min
TM
Cheng
D017209:Apoptosis / Q000187:drug effects; D002455:Cell Division / Q000187:drug effects; D006801:Humans; D008070:Lipopolysaccharides / Q000494:pharmacology*; D016212:Transforming Growth Factor beta / Q000032:analysis / Q000378:metabolism*; D053773:Transforming Growth Factor beta1; D020298:U937 Cells / Q000187:drug effects* / Q000378:metabolism; D042461:Vascular Endothelial Growth Factor A / Q000032:analysis / Q000378:metabolism*
D008070:Lipopolysaccharides; C508960:TGFB1 protein, human; D016212:Transforming Growth Factor beta; D053773:Transforming Growth Factor beta1; D042461:Vascular Endothelial Growth Factor A