title: Hepatocyte spheroid culture on a polydimethylsiloxane chip having microcavities.
abstract: A two-dimensional microarray technique of spherical multicellular aggregates (spheroids) using a microfabricated polydimethylsiloxane (PDMS) chip and the expression of liver-specific functions of primary rat hepatocytes on the chip were investigated. The PDMS chip, which was fabricated by a photolithography-based technique, consisted of approximately 2500 cylindrical microcavities (approximately 1100 cavities/cm2) in a triangular arrangement of 330 microm pitch on a PDMS plate (20 x 20 mm); each cavity measured 300 microm in diameter and 100 microm in depth. Most hepatocytes on the PDMS chip gradually gathered and subsequently formed a single spheroid in each cavity until 3 days of culture. A part of the spheroid was attached to the bottom or wall surface of the microcavity, and the spheroid configuration was maintained for at least 14 days of culture. Albumin secretion, ammonia removal and ethoxyresorufin O-dealkylase (EROD) activity, which is a cytochrome P-450-dependent reaction, of hepatocytes on the PDMS chip were higher than those of a monolayer dish or a flat PDMS dish without microcavities, and were maintained for at least 10 days of culture. The spheroid microarray technique appears to be promising in the development of cell chips and microbioreactors.
authors.affiliation: Department of Chemical Processes and Environments, Faculty of Environmental Engineering, The University of Kitakyushu, 1-1 Hibikino, Wakamatsu-ku, Kitakyushu, Fukuoka 808-0135, Japan. nakazawa@env.kitakyu-u.ac.jp
authors.forename: Kohji
authors.initials: K
authors.lastname: Nakazawa
authors.forename: Yumiko
authors.initials: Y
authors.lastname: Izumi
authors.forename: Junji
authors.initials: J
authors.lastname: Fukuda
authors.forename: Takashi
authors.initials: T
authors.lastname: Yasuda
mesh_terms: D000818:Animals; D001672:Biocompatible Materials; D015815:Cell Adhesion Molecules / Q000235:genetics; D002452:Cell Count; D017630:Connexins / Q000235:genetics; D018076:DNA, Complementary / Q000235:genetics; D004129:Dimethylpolysiloxanes; D022781:Hepatocytes / Q000166:cytology* / Q000378:metabolism; D039423:Integrin alpha1 / Q000235:genetics; D008422:Materials Testing; D046228:Microarray Analysis / Q000295:instrumentation*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D051381:Rats; D012828:Silicones; D018874:Spheroids, Cellular / Q000166:cytology* / Q000378:metabolism; D013499:Surface Properties; D000097002:Gap Junction beta-1 Protein
chemical_list: D001672:Biocompatible Materials; D015815:Cell Adhesion Molecules; D017630:Connexins; D018076:DNA, Complementary; D004129:Dimethylpolysiloxanes; D039423:Integrin alpha1; D012333:RNA, Messenger; D012828:Silicones; D000097002:Gap Junction beta-1 Protein; C013830:baysilon