Enhanced cell survival and yield of rat small hepatocytes by honeycomb-patterned films

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 μm. 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 μm showed the highest cell yield (approximately 3 times). Albumin production of mature hepatocyte on the pore sizes of 16u.m (224.1.3 ± 157ng ml^-1 well ^-1 at 1 day in culture, 369.5 ± 222 ng ml^-1 well^-1 at 3 days in culture) was higher than that of the hepatocytes on the flat films (119.3 ± 9.3 ng ml^-1 well^-1 at 1 day in culture, 262.8 ± 47.3 ng ml^-1 well^-1 at 3 days in culture), although that of small hepatocytes on the honeycomb-patterned films (pore size: 16 μm) 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.