title: Regulation of U-937 monocyte adhesion to cultured human mesangial cells by cytokines and vasoactive agents.
abstract: Leukocyte adhesion to kidney cells is an early event in renal inflammation, such as glomerulonephritis. We developed an experimental model of monocyte adhesion to cultured human mesangial cells. U-937 myelomonocytic leukaemia cells, similar to peripheral blood human monocytes, irreversibly bound to mesangial cell monolayers upon 30-180 min coincubations (to a max. of 13,600 +/- 1100/cm2 monolayer), as assessed by cell counting, U-937 labelling with 3H-thymidine, and colorimetry of nuclear staining with crystal violet. Adhesion was enhanced in mesangial cells proliferating in response to 17% fetal bovine serum, indicating expression of a proinflammatory phenotype. E. coli lipopolysaccharide (LPS), tumour necrosis factor-alpha (TNF-alpha) and protein kinase C activation with phorbol myristate acetate (PMA) potentiated monocyte binding during either coincubation or 24-h pretreatment (0.1 microM PMA, +200 +/- 21%). Binding was also promoted by pretreatment with vasoconstrictors, such as the thromboxane A2 mimetic, U-46619 (10 nM-1 microM, max. +35 +/- 3%), or 1 microM angiotensin II (+64 +/- 4%). To elucidate the mechanisms of monocyte adhesion, we analysed the adhesion molecules expressed by human mesangial cells, employing reverse transcription/polymerase chain reaction to detect ICAM-1, VCAM-1 and E-selectin gene expression. Proliferating cells express VCAM-1 and ICAM-1, confirmed by immunocytochemical staining and 79 +/- 3% inhibition of stimulated adhesion by pretreatment of mesangial cells with an anti-ICAM-1 monoclonal Ab. E-selectin transcription was not detectable.(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Division of Nephrology, University La Sapienza of Rome, Italy.
authors.forename: P
authors.initials: P
authors.lastname: Menè
authors.forename: S
authors.initials: S
authors.lastname: Fais
authors.forename: G A
authors.initials: GA
authors.lastname: Cinotti
authors.forename: F
authors.initials: F
authors.lastname: Pugliese
authors.forename: W
authors.initials: W
authors.lastname: Luttmann
authors.forename: K H
authors.initials: KH
authors.lastname: Thierauch
mesh_terms: D000704:Analysis of Variance; D001483:Base Sequence; D002151:Calorimetry; D002448:Cell Adhesion / Q000187:drug effects; D015815:Cell Adhesion Molecules / Q000378:metabolism; D002455:Cell Division; D016207:Cytokines / Q000494:pharmacology*; D019040:E-Selectin; D005920:Glomerular Mesangium / Q000187:drug effects / Q000473:pathology*; D005921:Glomerulonephritis / Q000235:genetics / Q000473:pathology*; D006801:Humans; D018799:Intercellular Adhesion Molecule-1 / Q000378:metabolism; D008969:Molecular Sequence Data; D009000:Monocytes / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D014407:Tumor Cells, Cultured; D019010:Vascular Cell Adhesion Molecule-1; D014662:Vasoconstrictor Agents / Q000494:pharmacology*
chemical_list: D015815:Cell Adhesion Molecules; D016207:Cytokines; D019040:E-Selectin; D019010:Vascular Cell Adhesion Molecule-1; D014662:Vasoconstrictor Agents; D018799:Intercellular Adhesion Molecule-1