Blood substitutes and antibodies to combat caries, harvested from plants – molecular farming provides a solution. Fraunhofer researchers are producing a number of valuable substances from tobacco. They were awarded Joseph-von-Fraunhofer special-merit prize.
Today, more than one in four pharmaceutical products are manufactured by means of biotechnology and genetic engineering. Until now, drugs such as insulin, interferon and vaccines against jaundice were mostly derived from bacteria or animal cell cultures. Yet these methods have several disadvantages: The proteins produced in bacterial or mammalian cell cultures can trigger immune responses or transmit pathogens such as HIV or viral strains of hepatitis. "Plants, on the other hand, do not produce any bacterial toxins, virus particles or pathogens that might represent a health risk for humans," points out Dr. Stefan Schillberg from the Fraunhofer Institute for Molecular Biotechnology and Applied Ecology IME. In future, Fraunhofer researchers therefore intend to harvest lots of pharmaceutical products from plants.
The scientists use plants as a type of "organic-factory" to produce drugs economically and safely. In the case of molecular farming, they incorporate an extra gene, such as the antibody that combats caries, in the genetic makeup of a plant. The genetically modified organism then automatically produces the new "recombinant" protein as it grows. Scientists then only need to isolate the active agent. "Another plus is the high quality of protein produced in plants, with its correct three-dimensional folding," says Schillberg. Moreover, it costs between 10 and 50 times less to manufacture high-quality active agents in plant cells by comparison with processes using bacteria or animal cell cultures. So far, Fraunhofer researchers have produced 150 different types of recombinant protein in tobacco, wheat and rice, e. g. a protein in human blood: serum albumin. "The tobacco plant is most suited to large-scale production of active agents. It can easily be genetically modified and cultivated at low cost. Tobacco generates a great volume of biomass per hectare and year, and thus produces the very high yield of the final product," says the biologist, summarizing the results.
Dr. Schillberg was awarded the 2001 Joseph-von-Fraunhofer special-merit prize for his work, in view of the pressing need for large quantities of novel therapeutic agents to diagnose and treat certain types of cancer and infectious diseases. Molecular farming is a cost-effective and reliable means of manufacturing pharmaceutical products on a large scale.
Fraunhofer-Gesellschaft. November 12, 2001.