ABSTRACT
Prior to the development of recombinant DNA technology, most human protein pharmaceuticals were available in a limited quantity. Such products were expensive to produce and their mode of action was not fully understood. Today, with the recombinant DNA technology, nearly 400 different proteins having potential human therapeutic agents have been cloned from bacteria. Most of these sequences have been expressed in host cells and are currently being examined for the cure of human diseases such as diabetes, cancer and hemophilia. Some of the human proteins that have been produced by recombinant DNA Technology are summarized in Table 8.1
A number of different methods are used to isolate either the genes or cDNAs for human proteins. In some cases, the target protein is isolated and a portion of the amino acid sequence is determined. From this information, a DNA coding sequence is deduced (Glick and Pasternak, 1998). The appropriate oligonucleotide is synthesized and used as a DNA hybridization probe to isolate the gene or cDNA from either a genomic or cDNA library. In some cases, antibiotics are raised against the purified protein and then used to screen a gene expression library (Glick and Pasternak, 1998).
