Permeability characteristics of human endothelial monolayers seeded on different extracellular matrix proteins

Objective: To investigate whether endothelial monolayer permeability change s induced by inflammatory mediators are affected by the extracellular matri x protein used for cell seeding. Methods: Human umbilical venular endothelial cells (HUVEC) were grown to co nfluent monolayers on membranes coated with either collagen, fibronectin or gelatin. The permeability to albumin and dextran was then assessed, both u nder normal conditions and after treatment with tumor necrosis factor-alpha (TNF-alpha) and bacterial lipopolysaccharide (LPS). Results: With any of the three protein coatings, tight junctions were forme d all over the monolayers. The permeability of the coated membranes to albu min and dextran was reduced strongly by confluent monolayers; the relative reduction was similar for the three matrix proteins used. Pre-incubation of the monolayers with either TNF-alpha or LPS increased permeability dose de pendently. However, the relative increase due to either treatment was indep endent of the protein used for membrane coating. Conclusion: The extracellular matrix protein used for initial seeding of en dothelial cultures plays a minor role in determining the permeability chang es induced in HUVEC monolayers by inflammatory mediators.