Researchers at Karolinska Institutet and the Feinstein Institute for Medical Research have discovered that the human immune system has a hitherto unknown role – blood pressure regulation. Collaborating with colleagues from Canada, they have found that a special kind of immune cell called acetylcholine-producing lymphocytes can regulate blood pressure in laboratory mice. The study, which is published in Nature Biotechnology, could open the way for new forms of treatment for hypertension.
High blood pressure, or hypertension, is a crucial risk factor for premature death around the world. Despite this, hypertension often has indeterminable causes, although it has long been known that the neurotransmitter acetylcholine plays an important part in that it causes blood vessels to relax and regulates blood pressure by influencing the production of nitric oxide. By studying laboratory mice lacking a certain kind of immune cell called acetylcholine-producing lymphocytes, a research group at Karolinska Institutet and their colleagues at the Feinstein Institute for Medical Research in New York and the University Health Network in Toronto have discovered that these immune cells have a previously unknown function: to reduce the blood pressure.
“These lymphocytes produce acetylcholine that can be delivered to target cells lacking direct contact with nerves,” says lead author Peder Olofsson, researcher at KI’s Department of Medicine in Solna. “It therefore seems that they can transmit signals for regulating the immune system and blood pressure. This is a new piece of the puzzle in our understanding of blood circulation.”, he said.