title: Monocyte intracellular cytokine production during human endotoxaemia with or without a second in vitro LPS challenge: effect of RWJ-67657, a p38 MAP-kinase inhibitor, on LPS-hyporesponsiveness.
abstract: In the present study, we investigated the effect of RWJ-67657, a p38 MAP kinase inhibitor, upon in vivo LPS-induced monocyte cytokine production and upon monocyte LPS-hyporesponsiveness. Thirty minutes before a single injection of LPS (4 ng/kg BW), healthy male volunteers received a single oral dose of RWJ-67657 at increasing dosages (0-1400 mg). Blood samples (pre-medication, 3, 6 and 24 h after LPS) were immediately incubated with LPS (reflecting LPS-hyporesponsiveness) or without LPS (reflecting in vivo monocyte stimulation) for 4 h at 37 degrees C. Following red blood cells lysis and white blood cell permeabilization, cells were labelled with alpha-CD14-FITC and alpha-IL-1beta, alpha-IL-12 or alpha-TNFalpha (PE-labelled), fixed, and analysed using flow cytometry. In vivo LPS injection resulted in an increased percentage of circulating monocytes producing IL-1beta, TNFalpha and IL-12 only at 3 h after the LPS injection. This was dose-dependently inhibited by RWJ-67657 treatment. LPS-hyporesponsiveness to in vitro LPS treatment was most prominent at 3 and 6 h after the in vivo LPS injection; compared with pre-medication monocytes, at these intervals a reduced percentage of monocytes produced IL-1beta, TNFalpha or IL-12 after the in vitro LPS stimulus. At t = 6 h, this LPS-hyporesponsiveness could dose-dependently be inhibited by RWJ-67657 treatment of the volunteers. We therefore conclude that p38 MAP kinase inhibition with RWJ-67657 inhibited monocyte production of cytokines following in vivo LPS injection. Treatment with RWJ-67657 also reversed the LPS-hyporesponsiveness. Whether this result can be extended to the clinical situation remains to be elucidated. Patients with sepsis or an otherwise high risk for multi-organ failure are potential study groups.
authors.affiliation: Reproductive Immunology, Medical Biology Branch, Department of Pathology, University of Groningen, The Netherlands. m.m.faas@med.rug.nl
authors.forename: M M
authors.initials: MM
authors.lastname: Faas
authors.forename: H
authors.initials: H
authors.lastname: Moes
authors.forename: J W
authors.initials: JW
authors.lastname: Fijen
authors.forename: A C
authors.initials: AC
authors.lastname: Muller Kobold
authors.forename: J E
authors.initials: JE
authors.lastname: Tulleken
authors.forename: J G
authors.initials: JG
authors.lastname: Zijlstra
mesh_terms: D019446:Endotoxemia / Q000097:blood*; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D005786:Gene Expression Regulation / Q000187:drug effects*; D006801:Humans; D007093:Imidazoles / Q000494:pharmacology*; D007375:Interleukin-1 / Q000096:biosynthesis* / Q000097:blood / Q000235:genetics; D018664:Interleukin-12 / Q000096:biosynthesis* / Q000097:blood / Q000235:genetics; D008070:Lipopolysaccharides / Q000008:administration & dosage / Q000494:pharmacology*; D008297:Male; D020928:Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors* / Q000502:physiology; D009000:Monocytes / Q000378:metabolism*; D011725:Pyridines / Q000494:pharmacology*; D012772:Shock, Septic / Q000097:blood; D014409:Tumor Necrosis Factor-alpha / Q000032:analysis / Q000096:biosynthesis* / Q000235:genetics; D048051:p38 Mitogen-Activated Protein Kinases
chemical_list: D004791:Enzyme Inhibitors; D007093:Imidazoles; D007375:Interleukin-1; D008070:Lipopolysaccharides; D011725:Pyridines; C400277:RWJ 67657; D014409:Tumor Necrosis Factor-alpha; D018664:Interleukin-12; D020928:Mitogen-Activated Protein Kinases; D048051:p38 Mitogen-Activated Protein Kinases