Today researchers at the Wyss Institute at Harvard Medical School unveiled a DNA nanorobot that can seek out and destroy leukemia cells, by administering a therapeutic payload that causes malignancies to self-destruct, all while leaving healthy cells untouched.
A technique for building structures from genetic material, called DNA Origami, was incorporated to fabricate what the researchers have deemed to be nanorobots, as they perform some robotic tasks. These clamshell-like bots, composed of DNA, were loaded with a single molecule known to halt cells from growing, eventually killing them. The nanorobot was programmed to "open," only when in contact with a diseased leukemia cell, in a manner similar to how combination lock works. If the correct combination between the leukemia and the nanobot is achieved, the clamshell unlocks, releasing the molecule. The team at Harvard fabricated millions of copies of the nanobots, and released them upon cancer cells, half of which were destroyed after three days.
Shawn Douglas, head of the team at Harvard, says that by adding additional payloads to shut down more of the cells' normal functioning, his team could target all of the leukemia cells. And also, by altering their "locks", the nanobots could be designed to target any type of cell. Douglas theorizes that a double-lock system on the bots will help them to differentiate between cancer and healthy, rapidly-dividing cells, like those in hair follicles, which are damaged during traditional chemotherapy.
This functionality achieves a whole new level of specificity that traditional drugs and delivery methods lack. Jørgen Kjems, head of the team in Denmark that created the first 3D DNA origami in 2009 says, "the group provides proof of principle that DNA origami has the capacity to create highly intelligent drugs that activate only on encountering diseased cells. This will inevitably lower the toxicity and side effects of the drugs carried within the device." He goes on to say, "the next step will be to ensure the DNA nanorobot can withstand the destructive environment of living organisms."