Enhanced Cell Survival and Yield of Rat Small Hepatocytes by Honeycomb-Patterned Films

Abstract

Surface designing of substrate to regulate cell adhesion and function in nano and micro scale is a critical issue in biomaterial science. In this study, we describe the fabrication of highly regular patterned porous films (honeycomb-patterned film) formed by a simply casting technique, and the culture of mature hepatocytes and small hepatocytes on the films. The pore size of the honeycomb-patterned films used was 6, 12, and 16 mm. We evaluated the effect of the honeycomb-patterned films on the morphology, cell yield, survival and the differentiated hepatic function (albumin production) of the both hepatocytes. Both hepatocytes attached on the flat films appeared to spread well, showing a typical monolayer morphology. They peeled off from the films at 7 days in culture on the flat films. On the other hand, spreading of the each hepatocytes was restricted on the honeycomb-patterned films at 3 and 7 days in culture. The cell yield and survival of the each hepatocytes increased with increasing culture time. Small hepatocyte on the pore sizes of 16 mm showed the highest cell yield (approximately 3 times). Albumin production of mature hepatocyte on the pore sizes of 16 mm (224:1:3 AE 157 ng ml À1 well À1 at 1 day in culture, 369:5 AE 222 ng ml À1 well À1 at 3 days in culture) was higher than that of the hepatocytes on the flat films (119:3 AE 9:3 ng ml À1 well À1 at 1 day in culture, 262:8 AE 47:3 ng ml À1 well À1 at 3 days in culture), although that of small hepatocytes on the honeycomb-patterned films (pore size: 16 mm) was similar on the flat film. These results indicated that both the surface topography and the pore size of the honeycomb-patterned film affected the hepatic metabolic function.

Breath Figure: A Nature-Inspired Preparation Method for Ordered Porous Films

“…Thus, the growth time is decided by the evaporation time. Shimomura and Yan et al reported that the diameter of the pores in BFA was easy to regulate by the thickness of the cast polymer solution because the evaporation time varied with the thickness. − For the same reason, the pores in the center of the BFA films are larger than those near the edge of the film because the thickness of the solution at the center of the drop is larger. , …”

Honeycomb structured polymer films via breath figures

“…A similar value of albumin production in flat films and the honeycomb film was observed for small hepatocytes. 159 A commercially available block copolymer polystyrene-b-polybutadiene-b-polystyrene was used to obtain honeycomb membranes that were photochemically cross-linked by UV-light. The membranes did not show cytotoxicity and upon exposure to radiation, the surface hydrophobicity decreased, which allowed for cell attachment and proliferation of the lung cancer cell line A549.…”

Two-dimensional nanoarchitectonics based on self-assembly

“…This produces ordered patterns of hexagonally-packed holes in organic materials similar to the arrangement of cavities in the wax of a honeycomb, and has been extensively demonstrated by Shimomura and coworkers [78][79][80]. Formation of such patterns has been realized with many substances [81,82], some of which can be used as media for cell culture [83,84], as a superhydrohobic surface [85,86], or as a superadhesive surface [87].…”