Engineered seeds contain Hepatitis A fighting
The prospect of drug-producing plants just got a step closer thanks to new
research in which scientists successfully produced plants whose seeds contain high levels of complex proteins
which closely resemble antibodies.
The study, which was lead by Belgium's Flemish Interuniversity Institute for Biotechnology (VIB)
and was funded through the EU-funded Pharma-Planta project, has been published online by the Proceedings of the National
Academy of Sciences.
Currently, many medicines are produced using bacteria, yeasts or animal cells that have been genetically
modified to produce human proteins such as antibodies. These can be used for both therapeutic and diagnostic purposes.
While these methods of drug production are effective, the production costs are high due to the need for well-equipped
laboratories and the high labor costs associated with maintaining the animal cell cultures.
For many years scientists have sought to genetically engineer plants which could produce these proteins.
Growing plants can be carried out on a large scale and does not require hi-tech equipment, meaning that production costs could
be dramatically lowered. However, for a long time scientists were only able to replace 1% of the plant's proteins with the desired protein.
Plant seeds to produce antibodies
A few years ago a group of researchers from the VIB modified a plant in such a way that the desired antibody was
produced in the seeds of the plant. The technique was a success, with the plants producing seeds in which the desired protein made up over
one third of the total protein amount. In addition to the higher yield, the seeds offer other advantages over other plant parts. Unlike the leaves
for example, seeds can be stored for a long time without losing the protein's effectiveness. This means a reserve can be kept on hand until the protein
is actually needed.
Now a team of VIB researchers has taken the research a step further creating Arabidopsis plants whose seeds contain high levels of a more complex antibody.
The antibody bears a close resemblance to its human equivalent, which protects cells against Hepatitis A infection. Furthermore, tests revealed that the plant-produced
antibody was as effective as ordinary human antibodies. According to lead author Bart Van Droogenbroeck, there is a lot of interest in the ability of
plants to produce high levels of more complex antibodies.
Now we know it can be viable, we will be carrying on investing in this research,' he told CORDIS News.
In particular, the researchers are interested in creating plants which can produce proteins that are too complex for microbes or fungi to produce.
Within the Pharma-Planta consortium, there are researchers working on plants which could produce HIV or rabies antibodies. The aim of the partners is to produce enough material to start a clinical trial.
As the plants are genetically modified, the project partners are also working closely with the regulatory authorities to ensure that biosafety concerns are addressed.
Source: CORDIS sources
planta FP6 program
of the National Academy of Sciences