Cell culture techniques have become vital to the study of animal cell structure, function, and differentiation and for the production of many important biological materials such as vaccines, enzymes, hormones, antibodies, interferons, and nucleic acids. Microcarrier culture introduces new possibilities and, for the first time, allows practical high-yield culture of anchorage-dependent cells (
1 ). In microcarrier culture, cells grow as monolayers on the surface of small spheres or as multilayers in the pores of macroporous structures that are usually suspended in culture medium by gentle stirring. By using microcarriers in simple suspension culture, fluidized or packed bed systems, yields of up to 200 million cells per milliliter are possible.
The following microcarrier examples described in the procedures represent the major types: (1) Cytodex™ (GE Healthcare) represents spherical microcarriers for anchoragedependent cells, mainly for vaccine production; (2) Cytopore™ (GE Healthcare) represents macroporous microcarriers for anchorage and suspension cells in stirred tank reactors, mainly for r-protein production and monoclonal antobodies; (3) Cytoline™ (GE Healthcare) represents weighed macroporous microcarriers for fluidized bed applications.