Viruses have been in the news a lot lately, almost always in a negative light. The COVID-19 pandemic has irrevocably changed our society in ways we are still discovering. While viruses can cause much pain and suffering, they have also been used to produce life-saving medications, and scientists have been using them for decades. Many people do not realize how viruses actually revolutionized the way that some diseases are treated.
But first, how does DNA work?
Before we get into how viruses can change our DNA, we should first talk about how DNA works and why it is important for some illnesses. DNA is transcribed into RNA, which is then translated into proteins. You can think of proteins as the building-blocks of cells. They are responsible for many of the processes that make cells work the way they are supposed to. When the DNA is not working properly, cells may start to slack on their responsibilities. You can think of DNA as an instruction manual for the cell, carrying information to build proteins. Because cells are the building blocks of our bodies, this can lead to serious diseases. So how do viruses help with this situation?
Viruses infect with new information
At their most basic level, viruses carry information. They are essentially DNA or RNA enveloped by an outer shell. Once viruses attach to a host cell, they inject their genetic material into the cell. The cell then unwittingly uses this viral DNA or RNA to make new virus particles, and the cycle continues. While this seems inherently bad, it is actually extremely useful for biochemists because it is an easy way to give cells new instructions. If biochemists can hijack a virus and alter the DNA or RNA inside, they could deliver this new DNA to someone whose DNA is not working properly. In this situation, changing DNA can treat illness.
How is gene therapy used now?
So far, there are only 2 FDA approved gene therapies, both of which utilize viruses. Luxturna is one such drug, used to treat Leber congenital amaurosis type 2 (LCA2). LCA2 is a rare congenital eye disease that affects the retina (the part of the eye that detects light) and progressively causes blindness. Luxturna is a virus that significantly increases vision in people with this disease, though it does not cure LCA2. Luxturna works by delivering healthy genes to cells in the retina via a virus.
The second FDA approved gene therapy is Novartis’ Kymriah. This drug uses a virus to treat a type of leukemia called B-cell acute lymphoblastic leukemia (ALL). This drug utilizes T-cells, an aggressive immune cell that can help attack cancer. T-cells are harvested from the patient, and re-wired using Kymriah to attack ALL
Viruses have been used to alter the molecular machinery of cells to treat patients with serious illnesses. How do you feel about gene therapies? Leave a comment below!
No content on this site should ever be used as a substitute for direct medical advice from your doctor or other qualified clinician, please see the disclaimer page