Adhesion behavior of human adipo-stromal cells on self-assembled monolayers with different surface densities or gradients of RGD peptide.

The objective of this study is to investigate the adhesion of human adipo-stromal cells on self-assembled monolayers (SAM) with different surface densities and gradients of Arg-Gly-Asp (RGD) peptide. The different densities and gradients of carboxyl groups on the SAM surface were prepared by a SAM exchange technique, and then RGD was chemically immobilized to allow the RGD surface density on the SAM to change over the range of 2.3-8.9 ng/cm(2) (3.0-12 pmol/cm(2)). The spreading area and survival percent of cells increased as the density of RGD immobilized on the SAM became high, whereas no dependence of the RGD density on the number of cells adhered was observed. The survival percent of cells tended to increase with an increase in the RGD immobilization for the carboxyl group-gradient SAM. This finding suggests the possibility that the cell adhesion can be regulated by controlling the RGD density or gradient of cell substrate.