Antibodies are proteins that can target and attack specific cells.
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An experimental treatment rejuvenates the immune systems of older mice and improves the animals’ ability to fight infections. If this treatment is effective in humans, it could reverse the age-related decline in immunity that makes older people more susceptible to illness.
These reductions may be due to changes in blood stem cells, which can develop into all types of blood cells, including important components of the immune system. As we age, a greater proportion of these stem cells tend to produce some immune cells than others. Jason Ross at Stanford University in California. This imbalance impairs the immune system’s ability to fight infection. It also promotes chronic inflammation, which accelerates aging and increases the risk of age-related diseases such as heart disease, cancer, and type 2 diabetes.
Ross and his colleagues have developed a treatment that uses antibodies, proteins that recognize and attack specific cells, to target these biased stem cells. Next, they tested the treatment on six mice aged 18 to 24 months. This is roughly equivalent to a human being between 56 and 70 years old.
One week after receiving the antibody injection, these abnormal stem cells in the mice had decreased by about 38 percent compared to six rodents of the same age who did not receive treatment. They also had significantly higher amounts of two types of white blood cells important for recognizing and fighting pathogens, and lower levels of inflammation.
“You can think of this as turning back the clock,” says Ross. “We are adjusting these percentages [immune] more similar cells [those of] A young adult mouse. ”
To test whether these changes result in a stronger immune system, the researchers vaccinated 17 older mice with a mouse virus. Nine of these mice had received antibody treatment eight weeks earlier. The researchers then infected rodents with the virus. After two weeks, the number of infected cells in the animals was measured and it was found that almost half of the treated mice (4 out of 9) had completely cleared the infection, compared to 1 out of 8 of the untreated mice. It turned out that there was only one.
Taken together, these findings demonstrate that antibody treatment rejuvenates the immune system of aged mice. Humans, like rodents, have more abnormal blood stem cells as they age, so a similar antibody treatment could also boost their immune systems, Ross said.
Such a possibility is still far away, robert signer at the University of California, San Diego. First, we need a better understanding of the potential side effects of treatments. In an accompanying article, Signer and his colleagues write: Yasar al-Fat KassResearchers, also at the University of California, San Diego, suggest that depletion of stem cells, even abnormal stem cells, may increase cancer risk. On the other hand, “if you have a better immune system, you’ll be better at investigating cancer, so we don’t know exactly what will happen yet,” Signer says.
Still, Ross says these findings are a promising advance in understanding age-related immune decline and how to reduce it.
Aging is the biggest risk factor for various diseases. “Rejuvenating or improving immune function in older adults could really help fight infectious diseases,” Signer says. “It may also have an impact on different types of chronic inflammatory diseases. That’s what’s so exciting here.”
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Source: www.newscientist.com
