Researchers at the Technion-Israel Institute of Technology in Haifa have discovered a way to reverse the aging process by removing old B lymphocytes – a kind of white blood cell in vertebrate immune systems – from old mice and forcing the production of young, potent cells to replace them. The findings were reported in the January 2011 issue of the scientific journal Blood.
“As with every aging process in the body, it is generally thought that immune system aging, including that of the B cell population, is a progressive process that cannot be stopped or reversed,” says lead researcher Prof. Doron Melamed of the Technion’s Rappaport Faculty of Medicine.
“But we have succeeded in showing that it is possible to turn back the aging process.”
The immune system gets weaker with age – a fact reflected by a significant increase in illness among the elderly, and a dramatic decrease in their ability to respond to vaccination. The B lymphocytes are major cellular components in the function of the immune system, and responsible for antibody production.
According to Melamed, many studies have shown the B cell population undergoes dramatic reductions with age as a result of a decline in the body’s ability to produce new B cells, and a selection process that leads to an accumulation of old B cells with a limited response capability.
Using old mice, the Technion researchers showed that active removal of the B cells changes the body’s cellular homeostasis and generates conditions of chronic deficiency in these cells. To overcome this, the body reactivates the bone marrow, forcing it to produce B cells again at a rate not different than that which exists in young mice. The researchers found that the newly generated B cells replaced the old cells that were removed and led to up to 400% improvement in the ability of the treated mice to respond to vaccinations.
“This paper shows – for the first time – that physiological aging is a regulated process that can be reversed,” Melamed concludes. “It also presents a novel approach for rejuvenating the immune system and for enhancing the efficacy of vaccination among the elderly population.”