Expression of CD73/ecto-5'-nucleotidase on human gingival fibroblasts and contribution to the inhibition of interleukin-1alpha-induced granulocyte-macrophage colony stimulating factor production.
OBJECTIVE
CD73/5'-nucleotidase (5'-NT) is an ectoenzyme that participates in immune/inflammatory reactions. We examined the possible expression of CD73/5'-NT on human gingival fibroblasts (hGF), which are important to the immune/inflammatory system in periodontal tissue.


RESULTS
We demonstrated that CD73/5'-NT was expressed on hGF by flow cytometry. We found that pre-treatment of hGF with 5'-AMP induced marked inhibition of granulocyte-macrophage colony-stimulating factor (GM-CSF) production from hGF upon stimulation with interleukin-1alpha (IL-1alpha) by enzyme-linked immunosorbent assay (ELISA). A specific inhibitor of 5'-NT, adenosine 5'-[alpha,beta-methylene] diphosphate blocked the inhibition of GM-CSF production, suggesting that adenosine converted from 5'-AMP acts on the inhibitory effects. The GM-CSF inhibition suggested that A3 receptor might be involved. The rank order of agonists was found to be (N6-benzyl-5'-N-ethylcarboxamidoadenosine) A3 receptor agonist > or = (2-chloroadenosine) non-selective agonist > (CGS-21680) A2A receptor agonist > adenosine > or = (N6-cyclohexyladenosine) A1 agonist. Further support for the main role of A3 receptor was the binding A3 antagonist [9-chloro-2-(2-furanyl)-5-([phenylacetyl]amino)[1,2,4]-triazolo[1,5-c]quinazdine] reversed the effect of adenosine, but no significant reverse was observed by A1 (1,3-dipropyl-8-cyclopentylxanthine), A2 [3,7-dimethyl-1-(2-propargyl)xanthine], A2A[8-(3-chlorostyryl)caffeine], and A2B (alloxazine) antagonists. The CD73/5'-NT expression was increased upon stimulation with gamma-interferon, but not other stimulants such as tumor necrosis factor-alpha, IL-4, lipopolysaccharide from Porphyromonas gingivalis and Escherichia coli, and fimbriae from P. gingivalis, and this increase was correlated with the enhanced GM-CSF inhibition by 5'-AMP but not adenosine.


CONCLUSIONS
These findings suggested that CD73/5'-NT on hGF exerts an anti-inflammatory effects in periodontal disease by conversion from 5'-AMP to adenosine.
Nemoto
Eiji
E
Division of Periodontology and Endodontology, Tohoku University Graduate School of Dentistry, 4-1 Seiryo-machi, Aoba-ku, Sendai 980-8575, Japan. eiji@mail.cc.tohoku.ac.jp
Kunii
Ryotaro
R
Tada
Hiroyuki
H
Tsubahara
Taisuke
T
Ishihata
Hiroshi
H
Shimauchi
Hidetoshi
H
D015720:5'-Nucleotidase / Q000032:analysis* / Q000037:antagonists & inhibitors / Q000494:pharmacology; D000241:Adenosine / Q000494:pharmacology; D058909:Adenosine A3 Receptor Agonists; D058918:Adenosine A3 Receptor Antagonists; D000249:Adenosine Monophosphate / Q000494:pharmacology; D000255:Adenosine Triphosphate / Q000031:analogs & derivatives* / Q000494:pharmacology; D000293:Adolescent; D000328:Adult; D002478:Cells, Cultured; D004791:Enzyme Inhibitors / Q000494:pharmacology; D004926:Escherichia coli; D005347:Fibroblasts / Q000201:enzymology*; D010861:Fimbriae, Bacterial / Q000502:physiology; D005881:Gingiva / Q000201:enzymology*; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000037:antagonists & inhibitors*; D006801:Humans; D007371:Interferon-gamma / Q000494:pharmacology; D007375:Interleukin-1 / Q000037:antagonists & inhibitors*; D015847:Interleukin-4 / Q000494:pharmacology; D008070:Lipopolysaccharides / Q000494:pharmacology; D016966:Porphyromonas gingivalis; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology
D058909:Adenosine A3 Receptor Agonists; D058918:Adenosine A3 Receptor Antagonists; D004791:Enzyme Inhibitors; D007375:Interleukin-1; D008070:Lipopolysaccharides; D014409:Tumor Necrosis Factor-alpha; D015847:Interleukin-4; D000249:Adenosine Monophosphate; D007371:Interferon-gamma; D016178:Granulocyte-Macrophage Colony-Stimulating Factor; D000255:Adenosine Triphosphate; D015720:5'-Nucleotidase; D000241:Adenosine; C002630:alpha,beta-methyleneadenosine 5'-triphosphate