Entrapment of animal cells for production of monoclonal antibodies and other biomolecules

Abstract

Animal cell technology is attracting considerable interest because of the capacity of animal cell cultures to synthesize or transform complex compounds such as virus vaccines, immunochemicals, hormones or enzymes. For the growth of surface-dependent cells, microcarrier technology is gaining importance. Here, we have attempted to immobilize surface-independent cells, normally grown in suspension, by entrapping them in polymer microbeads. Such entrapment should give increased stability to the normally fragile animal cells, allow for high cell densities to be achieved within the beads and make such preparations suitable for continuous operation. At the same time, the need for separation of the desired product from the cells is obviated. With the model systems studied, we showed that hybridoma, as well as other cell lines entrapped in agarose microbeads, remained viable. Both immunoglobulins and lymphokines were exported through the microbeads into the medium for 1-3 weeks, at levels corresponding well to those produced with free cells.

State-of-the-art of the production of retroviral vectors

“…In principle, animal cells can be cultivated in immobilization systems, where the cells are encapsulated [113][114][115][116][117] or entrapped in a polymer matrix, such as agarose [118] or alginate [119]. These capsules or beads are then cultivated in the form of suspensions in stirred tank reactors.…”

“Inverted Microcarriers” for Cell Cultures Made by Polymerization of Shells around Agarose Microspheres in a Non-Cytotoxic Procedure

“…6 Two different methods have been used for biocompatible embedding of cells in beads: the emulsion procedure, or extrusion facilitated by a coaxial air stream. Our approach attempted to combine the advantages 936 of both processes, and spherical microcapsules were formed instantaneously with a relatively homogeneous size.…”

“…We used a type (Sigma type IX) that gels around l5°C in a 1% solution in order to be able to mix with living cells before solidification of the gel. The micro beads were produced from an arrangement of two coaxial tubes: the living cells (5.10+ 6 ) in suspension in the agarose solution (0.5 ml) were extruded from the needle of a syringe (1 ml insulin syringe, 26G x 1/2" needle. Pharma plast.…”

Spatial distribution of sex chromosomes and ribosomal genes: A study on human lymphocytes and testicular cells

“…For three-dimensional evaluations of the arrangement of the sex chromo somes and the ribosomal genes in the nucleus we applied the agarose embed ding protocol of Nilsson et al (1983) with slight modifications. Stimulated and unstimulatcd lymphocytes were washed in PBS, fixed with 4% para formaldehyde and enclosed in 0.5% agarose (Sigma, type VII) without pre vious hypotonic treatment.…”