Researchers at the Fred Hutchinson Cancer Research Center in Seattle, USA, used gene editing to remove latent herpes simplex virus 1 (HSV-1), also known as oral herpes.
In mice, the technique showed a 92% decrease in latent virus, enough to prevent the infection from returning, according to the scientists. Effectively a cure for herpes. Even if it served to prevent the causes of contagion it would be a fantastic discovery.
Shred the virus
The study used two sets of "genetic scissors" to damage the virus's DNA, develop a delivery vehicle to infected cells and target the nerve pathways that connect the neck to the face, reaching the tissue where the virus lies dormant.
The results of this treatment method for herpes are published in Nature Communications.
“This is the first time that scientists have been able to go in and actually eliminate the majority of herpes in a human body,” says the study's author, the Dr Keith Jerome.
We are targeting the root cause of the infection: the infected cells where the virus lies dormant and are the “seeds” that give rise to repeat infections
Keith Jerome
Most research aimed at finding a cure for herpes has focused on suppressing the recurrence of painful symptoms. Jerome said his team is taking a completely different approach by focusing on how to cure the disease.
Next steps towards a cure for herpes
“The big leap now is to go from the test tube to an animal,” Jerome said. “I hope this study changes the dialogue about herpes research and opens up the idea that we can start thinking about the cure for herpes rather than just controlling the virus.”
According to the World Health Organization (WHO), two-thirds of the world's population under the age of 50 has HSV-1. The infection mainly causes cold sores and is permanent.
How the anti herpes method works
For this study, the researchers used two types of “genetic scissors” to cut the DNA of the herpes virus. They found that when using just one pair of “scissors,” the virus' DNA can be repaired in the infected cell.
However, by combining two “scissors” (two sets of gene-cutting proteins called meganucleases that focus on and cut a segment of herpes DNA) the virus falls apart.
“We use a double meganuclease that targets two sites on the DNA of the virus,” explained the first author Martine Aubert, senior scientist. “When there are two cuts, the cells seem to say that the virus's DNA is too damaged to be repaired, and other molecular players come in to remove it from the cell body.”
Researchers found a 92% reduction in viral DNA present in the upper cervical ganglia, the nerve tissue in which the virus lies dormant.
The reductions remained for at least a month after treatment, enough to prevent the virus from reactivating.
After fine-tuning their approach to a herpes cure, the team found that the method of using meganuclease cuts is also more efficient than CRISPR, the most current gene editing technique.
