Researchers have found another use for the gene-editing tool CRISPR, which can hold another significant application in the field of medicine.
The use of CRISPR may have gotten a bad rap following a controversial experiment in China that used the technology to create gene-edited babies. CRISPR, however, holds potentially beneficial uses. Earlier studies have already shown it can be used to fight drug-resistant bacteria and in eliminating HIV in lab animals.
James Collins, a bioengineer at the Massachusetts Institute of Technology in Cambridge, and colleagues used CRISPR to create smart materials that change their form on command. The researchers said that these shape-shifting materials could be used to deliver drugs and detect any biological signal.
For their study published in Science on Aug. 22, Collins and colleagues worked with DNA hydrogels — water-filled polymers held together by strands of DNA.
The researchers altered the properties of these materials using a form of CRISPR that uses the enzyme Cas12a.
The enzyme can be programmed to recognize a specific DNA sequence. Cas12a cuts its target DNA strands and then severs the single strands of nearby DNA.
This property made it possible for the researchers to build CRISPR-controlled hydrogels that contain a target DNA sequence and single strands of DNA that break after the Cas12a recognized the target sequence in a stimulus.
When the single DNA strands break up, they trigger the hydrogels to change shape or completely dissolve and release a payload.
Hydrogels Designed To Release Drugs In Response To Stimuli
Collins and his team created hydrogels designed to release enzymes, drugs, and human cells that can be used for therapy in response to stimuli. These gels could be used to make smart therapeutics that release drugs in response to a condition. They can deliver cancer drugs that will be released in the presence of a tumor or antibiotics for an infection.
"By incorporating DNA into materials, you can use this enzyme to control the properties of the materials in response to a specific biological cue in the environment," said study researcher MIT graduate student Max Atti English, who is part of the research team.