Biomedical Engineering Reference
In-Depth Information
Chapter 8
M
AMMALIAN
C
ELL
E
NCLOSING
C
APSULES
AND
F
IBER
P
RODUCTION IN A
C
O
-
FLOWING
A
MBIENT
L
IQUID
S
TREAM
Shinji Sakai
*
and Koei Kawakami
Department of Chemical Engineering, Kyushu University, Japan
Abstract
Mammalian cell-enclosing microcapsules have been investigated as devices for bioproduction,
cell therapy and stem cell research. Reduction in the diameter of the vehicles is an important
issue as it induces beneficial effects such as higher molecular exchangeability between the
enclosed cells and the ambient environment, as well as higher mechanical stability and
biocompatibility. In this chapter we describe the effectiveness of using a jetting process
involving the formation of a stretched thin jet of aqueous polymer solution and its subsequent
breakup into droplets in a co-flowing water-immiscible liquid for obtaining droplets of about
100 μm in diameter. The droplet production process and the processes for obtaining gelated
microcapsules through a thermal and peroxidase-catalyzed gelation process are also described.
In addition, we introduce the production of cell-enclosing hydrogel fibers using the same
device developed for the production of cell-enclosing microcapsules.
Introduction
Mammalian cell-enclosing microcapsules have been studied for more than 40 years as
research tools, as a device for the production of useful biomolecules such as antibodies and
enzymes, and as therapeutic devices for use in cell therapy to treat a variety of diseases such
as diabetes, liver failure, hemophilia and cancer [1-3]. More recently, this technology has
attracted attention as a feasible tool for investigating a niche of the differentiation pathway of
embryonic stem cells between the microenvironment
in vitro
and
in vivo
[4,5]. The injection
*
E-mail address: sakai@chem-eng.kyushu-u.ac.jp. Corresponding Author. Department of Chemical Engineering,
Faculty of Engineering, Kyushu University. 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan. Tel&Fax:
+81-92-802-2768.
