title: Immunoregulatory effects of adenosine 5'-triphosphate on cytokine release from stimulated whole blood.
abstract: In vitro studies suggest that extracellular nucleotides and nucleosides may be important regulators of inflammatory and immune responses. Most studies with adenosine 5'-triphosphate (ATP) have been performed in cell lines, which are remote from the human situation. The purpose of the present study was to determine the effects of ATP on TNF-alpha, IL-6 and IL-10 release in stimulated whole blood. Blood samples were drawn from healthy volunteers and incubated with ATP and lipopolysaccharide (LPS) + phytohemagglutinin (PHA) for 24 h. Contrary to expectations, ATP at 100 microM and 300 microM induced a reduction in TNF-alpha secretion by 32+/-8% (mean +/- SEM) and 65+/-4%, respectively. Furthermore, these ATP concentrations induced an increase in IL-10 secretion by 48+/-5% and 62+/-7% in whole blood. The ATP analogue adenosine 5'-O-(3-thiotriphosphate) (ATP-gamma-S) and adenosine 5'-diphosphate (ADP) also inhibited TNF-alpha release, but only ADP showed a stimulatory effect on IL-10. Co-treatment with adenosine deaminase did not reverse the ATP effect on TNF-alpha and IL-10. These results show, for the first time, that ATP inhibits the inflammatory response in stimulated whole blood as indicated by inhibition of TNF-alpha and stimulation of IL-10 release and that this effect is predominantly mediated by ATP and not by adenosine.
authors.affiliation: Department of Epidemiology, NUTRIM, Maastricht University, Maastricht, The Netherlands. e.swennen@farmaco.unimaas.nl
authors.forename: Els L R
authors.initials: EL
authors.lastname: Swennen
authors.forename: Aalt
authors.initials: A
authors.lastname: Bast
authors.forename: Pieter C
authors.initials: PC
authors.lastname: Dagnelie
mesh_terms: D000255:Adenosine Triphosphate / Q000494:pharmacology*; D000328:Adult; D001769:Blood / Q000187:drug effects* / Q000276:immunology*; D001773:Blood Cells / Q000187:drug effects* / Q000276:immunology / Q000378:metabolism; D002478:Cells, Cultured; D016207:Cytokines / Q000096:biosynthesis / Q000187:drug effects*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D007249:Inflammation / Q000276:immunology; D008070:Lipopolysaccharides / Q000494:pharmacology; D008297:Male; D008875:Middle Aged; D010835:Phytohemagglutinins / Q000494:pharmacology
chemical_list: D016207:Cytokines; D008070:Lipopolysaccharides; D010835:Phytohemagglutinins; D000255:Adenosine Triphosphate