The gut as a source of inflammatory cytokines after stimulation with endotoxin.
OBJECTIVE
To find out if endotoxin (LPS) can mediate the production of inflammatory cytokines by enterocytes.


METHODS
Laboratory experiment.


METHODS
Teaching hospital and burns unit, USA.


METHODS
Caco-2 cells (HTB38, human adenocarcinoma, and colon).


METHODS
Concentrations of tumour necrosis factor alpha (TNF-alpha), interleukin 6 (IL-6) and prostaglandin E2 (PGE2) in cell culture supernatants.


RESULTS
LPS significantly increased the production of TNF from 8.9 to 26.4 units/ml in 24 h and this increase persisted at a lower level for 4 days with an increase from 2.3 to 9 units/ml at a cell concentration of 2 x 10(5) cells/ml. There was no increase in TNF production when the cells were cultured at 5 x 10(5) cells ml with LPS. At a concentration of 2 x 10(5) cells/ml, the cells produced small amounts of IL-6 in 24 h or 4 day cultures with or without LPS. At a concentration of 5 x 10(5) cells/ml, LPS significantly increased IL-6 production in 24 h from 142 to 433 units/ml and from 106 to 250 units/ml in 4 days. The amount of IL-6 produced by LPS-stimulated cells was greater at 1 day than at 4 days. There was no significant difference in PGE2 production by the cells under any of the incubation conditions.


CONCLUSIONS
Enterocytes can produce TNF and IL-6, and endotoxin can increase the production of these cytokines by enterocytes. The gut therefore has the potential to become an important source of inflammatory cytokines.
Ogle
C K
CK
Department of Surgery, College of Medicine, University of Cincinnati, Ohio, USA.
Guo
X
X
Hasselgren
P O
PO
Ogle
J D
JD
Alexander
J W
JW
D018938:Caco-2 Cells; D016207:Cytokines / Q000096:biosynthesis*; D015232:Dinoprostone / Q000096:biosynthesis*; D006801:Humans; D007249:Inflammation / Q000378:metabolism*; D015850:Interleukin-6 / Q000096:biosynthesis; D008070:Lipopolysaccharides / Q000378:metabolism*; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis
D016207:Cytokines; D015850:Interleukin-6; D008070:Lipopolysaccharides; D014409:Tumor Necrosis Factor-alpha; D015232:Dinoprostone