Biol. Pharm. Bull., 27(9),1441-1443, September 2004

Notes

Exogenous Expression of Interferon-β in Cultured Brain Microvessel Endothelial Cells

Masaru NAKAMURA,^a Shinsuke YAMAGUCHI,^a Yoshihiko WATANABE,^b Fumiyoshi YAMASHITA,^a Yoshinobu TAKAKURA,^c and Mitsuru HASHIDA^*,a

^a Department of Drug Delivery Research, Graduate School of Pharmaceutical Sciences, Kyoto University; ^b Department of Molecular Microbiology, Graduate School of Pharmaceutical Sciences, Kyoto University; and ^c Department of Biopharmaceutics and Drug Metabolism, Graduate School of Pharmaceutical Sciences, Kyoto University; Sakyo-ku, Kyoto 606-8501, Japan. * To whom correspondence should be addressed. e-mail: hashidam@pharm.kyoto-u.ac.jp

Brain microvessel endothelial cells (BMECs) make up the blood-brain barrier (BBB) and regulate the passage of therapeutic proteins as well as drugs from the cerebrovasucular circulation to the brain. In the present study, we transferred mouse or human interferon-β (IFN-β) gene via cationic liposomes into primary cultures of bovine BMECs developed as an in vitro model of the BBB. The gene-transferred BMECs secreted transiently a substantial amount of IFN activity more efficiently during the growth phase than at confluence. This was suggested to be due to a difference in the potential for plasmid incorporation between growing and confluent BMECs in a series of cell association experiments with ³²P-labelled plasmid DNA. Furthermore, when BMEC monolayers in Transwell plates were transfected with the IFN-β-expression vectors from the upper side, IFN-β was predominantly detected in the upper compartments, suggesting polarized secretion of the transgene products in BMEC monolayers. These findings provide important basic information about therapeutic secretory protein gene delivery to BMECs.

Key words brain microvessel endothelial cell; interferon-β; polarized secretion; secretory protein; transfection