Studying the influence of electroporation on HT29 cell line interaction with fibronectin and collagen protein micro-patterned surface

Abstract

Micro-contact printing (MCP) is a scheme that allows a substrate or surface to be functionalized freely with extracellular matrix (ECM) protein such as fibronectin and collagen, in a well-defined manner. MCP can be used to regulate cell adhesion geometry on a substrate and in controlling wound healing process by facilitating directed cell migration. In this study, human colon cancer cell line, HT29 were grown on a micro-contact printed pattern of fibronectin and collagen protein with repeat gratings of 25μm, 50μm, and 100μm wide, for 48 hours. The cells alignments to the patterned substrates were then computed, where 0° means 100% alignment to the pattern. This was done with the purpose of finding those pattern that stimulated the best degree of cell alignment. Best alignment and elongation were obtained on 50μm of the two ECM proteins. The quantitative analysis of the results revealed that HT29 cells aligned most readily to the 50μm width pattern with a mean angle of alignment of 5.0-1.3 and 16.1-4.6, respectively, on fibronectin and collagen pattern surfaces. Contrarily, the cells aligned poorly on the 25μm width pattern of fibronectin, collagen and the control substrates with a mean angle of 33.4-8.4, 36.2-8.9 and 54.5-6.0, respectively. Furthermore, the 50μm stamp pattern was used to investigate the influence of pulse electric field (PEF) on the HT29 alignment to the patterned substrate. The result revealed that there was significant improvement (P < 0.05) in the cell alignment between the electrically treated and the untreated cells. The alignment angles of the electrically treated cells were 4.0-1.2 and 11.2-3.5, respectively, on the 50μm pattern surface of fibronectin and collagen. Therefore, the result of the study revealed that micro-contact printing technique together with pulse electric field could offer a potentially fast method of controlling directed cell migration for wound healing application.