Use of recombinant DNA technology for engineering mammalian cells to produce proteins.

The recent advances in molecular biology have merged with somatic cell genetics and cell biology to allow mammalian cells to be extremely useful for the expression of foreign genes. This chapter has focused primarily on the approaches and potential limitations to high-level expression of proteins in mammalian cells. Future developments will involve the modification of mammalian cells in order to increase the efficiency of the various steps in protein processing and secretion. The ability to genetically engineer mammalian cells to produce high levels of desired proteins is presently complemented by advances in biochemical engineering which involve the ability to grow mammalian cells in very large volumes or at very high densities with reduced serum requirements. As a result, the cost for production of gram quantities of a protein from a mammalian host cell are approaching the cost of proteins from a mammalian host cell are approaching the cost of proteins similarly derived from microbial systems with all the advantages that mammalian systems afford.