Differential responses of endothelial cells on three-dimensional scaffolds to lipopolysaccharides from periodontopathogens.

Studies have been conducted on the pathogenicity of periodontopathogens in cultures of endothelial cells on two-dimensional (2D) polystyrene surfaces, where the monolayer formed is not exposed to proteins of the subendothelial matrix. In this work, we developed a culture system by seeding human coronary artery endothelial cells (HCAECs) onto three-dimensional (3D) scaffolds of collagen type I, a subendothelial protein. The inflammatory responses of the HCAEC monolayers, formed either on 3D scaffolds or directly on a 2D polystyrene plate, to lipopolysaccharide (LPS) from Aggregatibacter actinomycetemcomitans (Aa) and Porphyromonas gingivalis (Pg) were evaluated. The transcription of 3 genes, the secretion of 40 cytokines and 2 prostanoids, and the adhesion of monocytes to 2D and 3D cultures with or without exposure to lipopolysaccharides (control) were assessed. HCAECs exhibited differences in transcriptional and secretory profiles between the 3D and 2D models. In addition, the inflammatory responses of HCAEC to Aa-LPS and Pg-LPS differed between the two models. In 3D cultures treated with Aa-LPS, the levels of IL-8, RANTES, G-CSF, ICAM-1, IL-6, and TXA2 were significantly higher than those in the controls. In 2D cultures treated with Aa-LPS, IL-8, RANTES, G-CSF, ICAM-1, TNF-RI, PGI2, and TXA2 levels were significantly higher than those in their controls. In the presence of Aa-LPS, monocyte adhesion did not differ between treated and control 3D cultures but was significantly higher in treated 2D cultures than in the controls. In response to Pg-LPS, cytokine-prostaglandin secretion and monocyte adhesion did not differ between 3D and 2D cultures. These data indicate that HCAECs respond differently to these two types of LPS.