Micropatterning Studies of antibodies on PLCL

Abstract

Tissue engineering would, more often than not, require cells to be instructed in their growth, so as to align to a specific direction or to differentiate into a specific type of cell. Micropatterning of biomacromolecules onto biocompatible polymers has been a suggested answer to this need. Since most polyesters are hydrophobic and therefore have low cell affinity, surface modification serves as a solution. In this study, spincoated compolymer poly(L-lactide-co ε-caprolactone) (PLCL) film was modified by aminosilane and crosslinked by glutaraldehye for the immobilization of FITC-conjugated gelatin dot and line micropatterns using PDMS. Water contact angle measurements showed increased surface wettability for gelatin-immobilized PLCL films. Immobilization of micropatterns was confirmed by fluorescence microscopy and samples were seeded with human umbilical vein endothelial cells (HUVECs) and cultured for 5 days. HUVECs imaged via inverted microscope showed that the cells were easily directed by line patterns while it took a longer period of time to see the influence of dot patterns. Alamar Blue (AB) assay was done for days 1, 3 and 5. AB fluorescence intensity showed good cell activity on day 1 but subsequent tests showed low cell activity. The HUVECs were fixated and stained for vinculin, F-actin and nucleus for the 3 time points but confocal laser imaging was unable to detect the dyes. These results suggest that PLCL may not be suitable for HUVEC growth.