title: Activation of adenosine A2A receptors inhibits neutrophil transuroepithelial migration.
abstract: Adenosine has been identified as a significant inhibitor of inflammation by acting on adenosine A(2A) receptors. In this study, we examined the role of adenosine and A(2A) receptors in the transmigration of human neutrophils across an in vitro model of the transitional bladder urothelium. Human uroepithelial cells (UROtsa) were grown on transwell inserts; uropathogenic Escherichia coli (UPEC) and neutrophils were added to the transwell system; and the number of migrating neutrophils was evaluated. Reverse transcription-PCR (RT-PCR), immunohistochemistry, and flow cytometry were used to investigate the expression of adenosine receptors, the epithelial adhesion molecule ICAM-1, and the neutrophil integrin CD11b. Levels of proinflammatory interleukin-8 (IL-8) and phosphorylated IκBα were measured by enzyme-linked immunosorbent assays (ELISA) and Luminex assays, respectively. The neutrophils expressed all four adenosine receptor subtypes (A(1), A(2A), A(2B), and A(3) receptors), but A(3) receptors were not expressed by UROtsa cells. UPEC stimulated neutrophil transuroepithelial migration, which was significantly decreased in response to the specific A(2A) receptor agonist CGS 21680. The inhibitory effect of CGS 21680 on neutrophil migration was reversed by the A(2A) receptor antagonist SCH 58261. The production of chemotactic IL-8 and the expression of the adhesion molecule ICAM-1 or CD11b were not significantly affected by CGS 21680. However, a significant decrease in the level of phosporylated IκBα was revealed in response to CGS 21680. In conclusion, UPEC infection in vitro evoked neutrophil migration through a multilayered human uroepithelium. The UPEC-evoked neutrophil transmigration decreased in response to A(2A) receptor activation, possibly through inhibition of NF-κB signaling pathways.
authors.affiliation: School of Natural Sciences, Linnaeus University, Kalmar, Sweden.
authors.forename: Susanne
authors.initials: S
authors.lastname: Säve
authors.forename: Camilla
authors.initials: C
authors.lastname: Mohlin
authors.forename: Ravi
authors.initials: R
authors.lastname: Vumma
authors.forename: Katarina
authors.initials: K
authors.lastname: Persson
mesh_terms: D039481:CD11b Antigen / Q000032:analysis; D054441:Cell Migration Assays, Leukocyte; D002465:Cell Movement; D002478:Cells, Cultured; D004797:Enzyme-Linked Immunosorbent Assay; D004926:Escherichia coli / Q000472:pathogenicity; D005434:Flow Cytometry; D054884:Host-Pathogen Interactions; D006801:Humans; D020672:I-kappa B Proteins / Q000032:analysis; D007150:Immunohistochemistry; D018799:Intercellular Adhesion Molecule-1 / Q000032:analysis; D016209:Interleukin-8 / Q000032:analysis; D000072000:NF-KappaB Inhibitor alpha; D009504:Neutrophils / Q000276:immunology / Q000502:physiology*; D043705:Receptor, Adenosine A2A / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D019459:Urothelium / Q000276:immunology*
chemical_list: D039481:CD11b Antigen; D020672:I-kappa B Proteins; C509295:ITGAM protein, human; D016209:Interleukin-8; C000606204:NFKBIA protein, human; D043705:Receptor, Adenosine A2A; D018799:Intercellular Adhesion Molecule-1; D000072000:NF-KappaB Inhibitor alpha