Japanese scientists have developed a vaccine to target so-called zombie cells that pile up over time and damage healthy cells. These cells are thought to be responsible for a range of age-related ailments, such as heart disease.
The research, published on Friday in the online version of the Nature Aging journal, found a reduction in the number of zombie cells – clinically known as senescent cells – in mice that were administered the vaccine. The effect was also seen in areas of the bodies that were affected by stiffening of arteries.
Senescent cells are popularly known as zombie cells as they stop dividing like normal cells but do not die. They start out as normal cells, but after experiencing a stress event – such as sustaining damage to their DNA or becoming infected with a virus – they enter a state of suspended animation rather than dying.
As they accumulate in the body, these cells damage neighboring healthy cells by releasing chemicals that cause inflammation. Over time, they facilitate the aging process and set the stage for a variety of medical conditions, including diabetes, osteoporosis, Alzheimer’s disease, enlargement of the heart, kidney problems, clogged arteries, and age-related loss of muscle.
In recent years, a number of studies with mice have trialed drugs called senolytics that kill these zombie cells. But the Japanese team, which included researchers from universities across the country, identified a protein found in senescent cells in humans and mice and synthesized a vaccine based on an amino acid that helps make up the protein.
This peptide-based vaccine allows the body to create antibodies that can attach themselves to senescent cells, which can then be removed by white blood cells that adhere to the antibodies. According to study author Tohru Minamino, the vaccine can be “applied to the treatment of arterial stiffening, diabetes and other aging-related diseases.”
When the researchers administered the vaccine to mice with clogged arteries, they found a reduction in the buildup of senescent cells and shrinking of the areas affected by the disease. The team stated that when older mice were injected, it slowed down the age-related body weakening process favourably in comparison to unvaccinated mice.
There were also apparently fewer side-effects from the vaccine, which has a longer-lasting effectiveness period than existing senolytics, according to the study.
