Business Potential for Agricultural Biotechnology - Asian Productivity ...

8. TRENDS IN KOREAN ANIMAL BIOTECHNOLOGY
AND PRODUCTION OF TRANSGENIC LIVESTOCK
HARBORING RECOMBINANT HUMAN PROTEINS
IN MILK AND URINE
Poongyeon Lee
Transgenic Research Lab, Animal Biotechnology Division
National Livestock Research Institute, RDA
Suwonn
INTRODUCTION
The Republic of Korea has a large number of government institutes which research genetically
modified organisms (GMOs). Although the issue of GM food safety has not been settled,
several GM crops are currently being imported as food ingredients as well as for industrial purposes
(Rural Development Administration, 2005). On the other hand, many researchers as well
as biocompanies are in favor of GMOs that produce useful materials, since the organisms are accepted
more easily by the general public when compared with GM food itself (Rural Development
Administration, 2005). This report will emphasize the field of animal biotechnology in
Korea, which has produced the most promising results.
Therapeutic proteins, especially glycoproteins, are manufactured primarily from cultured
animal cells. Production of pharmaceutical glycoproteins in cultured animal cells presents several
problems: varying glycosylation levels, high cost of culture media, difficulties in scaling-up,
etc. (Dimond, 1996). Fabrication of such proteins in transgenic animals is cost-effective and
relatively easy to scale up to match the increasing demand for therapeutic proteins, whose supply
is restricted due to bottlenecks in their production. Using established purification systems for the
glycoproteins from milk (or urine), production of therapeutic proteins from transgenic animals is
highly cost-effective (Van Berkel et al., 2002). Although manufacture of pharmaceutical human
proteins from transgenic animals is considered feasible using cost-effective bioreactor systems,
only a few existing businesses seem successful in producing such animals (PPL, GTC, Pharming).
Only a single product that has completed clinical trials and reached the market, after
decades of research, but researchers and the pharmaceutical industry have continued pursuing
the technology in the hope of achieving this goal within the next few years.
Transgenic farm animals have many uses in the fields of biotechnology and pharmaceutical
development. Researchers and biotechnology firms are attempting to construct a human-lke research
model explore how a disease develops and reacts to drugs and to test the purity of recombinant
human proteins produced by external sources. One of the primary goals in producing
transgenic farm animals is to create an animal bioreactor—a pharmaceutical production unit.
Using transgenic technology such as microinjection, genes that code for the production of a
human protein are inserted into the genome of an animal, which in turn produces the human
protein. Production of recombinant human protein is targeted to specific tissues, or organs that
produce body fluids, that can be relatively easily collected and purified. Examples of such body
fluids are blood, milk, urine, and seminal fluid (Houdebine, 2000).
The first breakthrough in producing a transgenic farm animal came in 1985, when the first
transgenic sheep was created (Hammer et al., 1985). The production of transgenic farm animals
recently garnered a new name, “pharming,” meaning “the production of pharmaceutical human
proteins in transgenic farm animals” (Krimpenfort et al., 1991). There are two major targets for
the production of foreign protein from the transgenic animal: milk and urine. Although controlling
quality and quantity of production of recombinant proteins in the transgenic animal is diffi-
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