title: Coculture conditions alter endothelial modulation of TGF-beta 1 activation and smooth muscle growth morphology.
abstract: We examined whether endothelial cells (ECs) inhibit smooth muscle cell (SMC) transforming growth factor-beta 1 (TGF-beta 1) activation in bilayer coculture. Western analysis showed that SMCs cocultured with ECs as a bilayer had lower amounts of active TGF-beta 1 protein compared with SMCs cultured alone and SMCs cocultured with ECs as a monolayer. EC inhibition of TGF-beta 1 activation could be blocked with plasminogen activator inhibitor-1 (PAI-1) antibody. Similarly, SMC hill-and-valley growth, a marker for TGF-beta 1 activity, was present in SMCs cultured alone and SMCs cocultured with ECs as a monolayer but was absent in SMCs cocultured as a bilayer. SMCs cocultured with ECs as a bilayer migrated at a greater rate than SMCs cultured either alone or cocultured as a monolayer. The EC effect on SMC migration was inhibited by the addition of 5 ng/ml TGF-beta 1. ECs had no effect on SMC RNA levels of TGF-beta 1. PAI-1 levels were increased in ECs and ECs cocultured with SMCs compared with SMCs cultured alone. ECs inhibit TGF-beta 1 activation in bilayer coculture. This appears to be mediated through an increase in EC PAI-1 release. Alterations in coculture conditions, in particular the degree of EC-SMC cell contact, have profound effects on this process.
authors.affiliation: Section of Vascular Surgery, Yale University School of Medicine, New Haven, Connecticut 06520, USA.
authors.forename: R J
authors.initials: RJ
authors.lastname: Powell
authors.forename: J
authors.initials: J
authors.lastname: Bhargava
authors.forename: M D
authors.initials: MD
authors.lastname: Basson
authors.forename: B E
authors.initials: BE
authors.lastname: Sumpio
mesh_terms: D000818:Animals; D000906:Antibodies / Q000494:pharmacology; D002417:Cattle; D002455:Cell Division; D002465:Cell Movement; D018920:Coculture Techniques; D017077:Culture Media, Conditioned; D004730:Endothelium, Vascular / Q000166:cytology / Q000502:physiology*; D009131:Muscle, Smooth, Vascular / Q000166:cytology*; D017395:Plasminogen Activator Inhibitor 1 / Q000502:physiology; D016212:Transforming Growth Factor beta / Q000378:metabolism* / Q000494:pharmacology
chemical_list: D000906:Antibodies; D017077:Culture Media, Conditioned; D017395:Plasminogen Activator Inhibitor 1; D016212:Transforming Growth Factor beta