Every cell in your body contains the same set of DNA, the entire set of instructions that makes you, you.
Think of each DNA molecule as a cookbook with every recipe a cell needs to live. Collectively, all the DNA in a cell comprises a bookshelf of cookbooks.
RNA molecules are copies of parts of your DNA that relay the instructions to make a specific protein throughout the cell.
Cells don’t like to waste energy; you wouldn’t want to grab an entire cookbook off the shelf every time if you didn’t have to. So think of RNA as making a copy of a single recipe to bring to the cook.
RNA molecules are copies of parts of your DNA that relay the instructions to make a specific protein throughout the cell. Besides being the finished product (or food in our analogy), proteins are needed to do almost everything in a cell.
The process shown above is known as the Central Dogma of Biology and describes how information is used in a cell.
So why is this useful? If we have a desired end product (protein, or biologic in our case) and we know we get to that end product using the Central Dogma, we can work backwards to get the instructions for making that end product.
Proteins describe many different molecules such as lipase (used in laundry detergent to break down fats), gluten (the non-water-soluble parts of wheat flour), and lactase (gut enzyme necessary to break down lactose). In the biopharmaceutical industry, proteins are most commonly manufactured in the form of monoclonal antibodies.
The gold standard in biotechnology is Chinese Hamster Ovary (CHO) cells. CHO cells are particularly useful because they are easy to grow in large quantities and are conducive to producing human-compatible proteins. Instead of a traditional factory, each CHO cell acts like a tiny bio-factory, producing the protein we want as long as we feed it the right food or materials. The most common type of protein produced in the biopharmaceutical industry is the monoclonal antibody (mAB).
We developed our master cell bank (the cells from which all future cells will be cloned) by modifying the DNA of CHO cells (called recombinant DNA technology) to tell the CHO cells to produce our mAB of interest, Risankizumab.
The CHO carry out the instructions in its DNA by creating RNA copies of these instructions. The process of creating protein from RNA is called translation. CHO cells are handy because they allow for post-translational modifications.
Post-translational modification is important because it allows us to modify the mAB to create a humanized antibody. These modifications allows humans to accept the antibody, which originally came from a different species (hamster in the case of CHO).
