So far, each protein gene inserted in the P-gel matrix has worked successfully, regardless of the protein’s size, type, or function. “This appears to be a universal and versatile production system,” says Dr. Biloski. “Moreover, the P-gel method makes it possible to make proteins that cannot be made in cell-based systems, including large, insoluble proteins and proteins that would kill E. coli or cells currently used to manufacture them.”
Because no living organisms are involved in the P-gel system and protein expression relies totally on enzymatic reactions, most proteins can be produced within the gel with stable production rates. Currently, 15–50 milligrams of protein per milliliter of reaction are made in the P-gel, and the company is scaling up to kilogram amounts.
The P-gel can be reused multiple times, making it suitable for automated multi-pass protein expression systems. Since the P-gel method lends itself to setting up highly consistent cGMP processes, it also may reduce regulatory hurdles for therapeutic proteins. Patients, too, may benefit, as cheaper generic drugs are manufactured in P-gels, Dr. Biloski says.
There are many benefits to the P-gel system, according to Dnano. It eliminates the need to build expensive cell-based manufacturing facilities; it reduces production costs to levels similar to that for small molecule drugs; it eliminates worries about contamination by prions and viruses, and it allows for continuous sampling during protein expression. “You can take out samples and analyze them to prove that the protein made at the beginning process is identical to the end process. You can’t do that with sealed cell-based systems,” explains Dr. Biloski.
It takes about a day to make a protein in the P-gel, compared to weeks and months for cell-based systems. After a protein is synthesized in the P-gel, separation and purification are easier as well. Cell membranes and other components of the cell-based systems such as carbohydrates and lipids do not have to be removed. Straightforward chromatography is often sufficient to purify proteins made in the P-gel.
Dnano is producing proteins for the R&D divisions of some large pharmaceutical and biotechnology companies in pilot studies. It plans to expand services to therapeutic protein manufacturing and/or provide nonexclusive licensing for the pharmaceutical and biotech industries. In the future, the company plans to produce investigational proteins as drug targets, biomarkers, or therapeutic agents. Eventually, it may retain the option to manufacture and market generic protein drugs. “Our method is simple and fast, and we have no doubts that we can transfer it to other people’s laboratories,” concludes Dr. Biloski.