Researchers at the University of Calgary have discovered a ground breaking new way to produce insulin from plants, a process they hope will make insulin more affordable for diabetics.
Dr. Maurice Moloney from the department of Biological Sciences has been leading the research. He has collaborated with Dr. Morley Hollenberg from the faculty of Medicine.
Currently insulin costs about $800 a gram in the western world. The cost of producing insulin with bacteria is about $65 to $75 a gram. The rest of the cost comes from production, bottling and safety standards. The plant-based insulin should bring the production cost down to $30 a gram, but the other costs will still be there, said Moloney.
"It's expensive to make because, first of all, insulin is not a very simple molecule, it does have some specialized folding and shapes associated with it which can only be achieved using specialized technology," said Moloney, who further noted that insulin is currently produced in large quantities using the bacteria E. coli.
"The bacteria E. coli, which has normally got a bad reputation for other types of illness, is used as the standard production organism for a lot of protein pharmaceuticals," said Moloney.
"Seeds are very good at storing proteins and so they actually store quite a lot of insulin," said Moloney. "The other side of it is, the technology we've developed . . . enables us to get the plants to do part of the purification work . . . so you can purify it a lot more inexpensively."
By changing the genes of the safflower plant Moloney and his team are able to make the oil-producing seeds produce insulin.
"The reason we've chosen it is that although it is a major oil seed in Asia, in North America there's only about 100,000 hectares of safflower grown and, as a result, we can biologically isolate insulin containing safflower from all of the food grade safflower that is produced," said Moloney.
"It's interesting because you might think you would be looking at millions of acres of this stuff. The fact is you could grow the current world supply of insulin on roughly 15,000 acres. Fifteen thousand acres is basically, in prairie terms, three farms."
Moloney said he found a way to attach the proteins to structures called oil bodies, which are where plants store vegetable-oil in all oil seeds.
By having the insulin protein in the oil body the extraction process is simplified. The oil body floats on water making it easy to simply skim the insulin off the top of the solution, said Dr. Hollenberg.
"What Dr. Moloney realized is that you can trick the plant's gene into extending the oil body protein so that the water soluble part could make the structure of insulin or any other protein that you want it to make," said Dr. Hollenberg.
Dr. Hollenberg helped test how the new insulin worked at the receptor level. According to Hollenberg, lab tests determined that it performed exactly like other insulin.
The first stage of official testing the insulin went through was chemical and biochemical based. The second stage was testing on animals to ensure that the insulin works and doesn't have any serious side effects said Moloney.
"They [the FDA] accepted our data as being indicative that we had the real product and so then we went into human clinical trials," said Moloney. "We were able to demonstrate that the plant-derived insulin is bioequivalent to the North American standard of care for treating diabetes right now."
Moloney stated that the technology resulted in the creation of a new company called SemBioSys, which has continued to test and research the insulin.