Release of TNF-alpha from lipopolysaccharide (LPS)-stimulated Kupffer cells in serum- and nutrient-free medium.
In monocytes/macrophages LPS stimulation occurs by the binding of LPS and the serum component LPS-binding protein (LBP) to CD14. This study was conducted to investigate whether this mechanism also occurs in Kupffer cells. Rat Kupffer cells were stimulated for up to 8 h by LPS (0, 100 ng/ml, 10 microg/ml) in RPMI medium or in nutrient-free Krebs-Henseleit (KH) buffer. Some incubations were performed without serum, while in others serum was provided. TNF-alpha concentrations of the supernatants were measured by ELISA. LPS stimulation of Kupffer cells yielded the following results. In KH without any additives a considerable amount of TNF-alpha was released. Incubation in RPMI without serum caused twice as much TNF-alpha to be released as when KH was used. The addition of autologous serum to RPMI did not increase TNF-alpha response. These results provide evidence that a substantial part of TNF-alpha release by LPS-stimulated Kupffer cells occurs in a serum- and thus LBP-independent way.
Zipfel
A
A
University of Tübingen, Department of General Surgery, Germany.
Schenk
M
M
Metzdorf
B
B
Bode
C
C
Viebahn
R
R
D000818:Animals; D018929:Cell Culture Techniques; D016895:Culture Media, Serum-Free; D004305:Dose-Response Relationship, Drug; D007700:Kinetics; D007728:Kupffer Cells / Q000187:drug effects / Q000378:metabolism*; D008070:Lipopolysaccharides / Q000494:pharmacology; D008297:Male; D051381:Rats; D011917:Rats, Inbred Lew; D012709:Serum Albumin / Q000494:pharmacology; D012710:Serum Albumin, Bovine / Q000494:pharmacology; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism*
D016895:Culture Media, Serum-Free; D008070:Lipopolysaccharides; D012709:Serum Albumin; D014409:Tumor Necrosis Factor-alpha; D012710:Serum Albumin, Bovine