Adhesion and proliferation of human vascular cells on UV-light-modified polymers

We studied the adhesion and proliferation of human umbilical-vein endothelial cells (HUVEC) and human aortic smooth-muscle cells (HASMC) on modified polymer samples. The polymers under investigation were either PTFE (polytetrafluoroethylene) or PET [poly(ethylene terephthalate)], which are among the most frequently employed biomaterials in reconstructive medicine. The polymer surfaces were modified by exposure to the UV light of an excited-xenon-dimer (Xe2*) Excimer lamp (Heraeus-Noblelight, Hanau, Germany) at a wavelength of 172 nm in an NH3 atmosphere. On modified PTFE, this resulted in a significant increase in the number of adhering HUVEC or HASMC 1 day after seeding and in the formation of a confluent cell layer after 3-4 days. On PET, HUVEC adhesion and proliferation rates were already high on untreated samples and could not be significantly increased by the UV-light treatment, but the cells were distributed more homogenously on the treated samples. Cell proliferation was in all cases comparable with, or even better than, that obtained on standard polystyrene (PS) Petri dishes used in cell cultivation. As on PS Petri dishes, the proliferation of HASMC on modified PTFE was faster than that of HUVEC under similar culture conditions.