A white blood cell, also known as a T cell, carries special structures on its surface with which to recognise specific pathogens. (Grapics: Blausen.com, CC BY 3.0 via Wikimedia Commons)
A balanced, non-GMO organic diet, exercise, meditation while identifying and removing stress enablers are key components for a healthy life. Courtesy of Peter Rüegg @ ETH Zurich:
You’re up in the mountains, the snow is blindingly white, and the sun is blazing down from the sky: ideal skiing conditions – but any skiers carrying the herpes virus might also have to reckon with the onset of cold sores after their day out. Increased exposure to UV radiation releases free radicals in the body. These put the body under oxidative stress, which weakens the immune system. And that in turn allows the herpes virus to prosper.
Oxidative stress has become a major topic; not only is it implicated in many diseases, it may even be one of their causes. Other environmental influences besides UV radiation can also increase oxidative stress on the body, including air pollution, smoking and the consumption of alcohol, and not least infections. Again and again, the talk is of fighting these free (oxygen) radicals by supplementing our diet with the appropriate vitamins.
T cells divide after contact with the enemy
Researchers working with Manfred Kopf, a professor at ETH Zurich’s Institute of Molecular Health Sciences, took these questions as their starting point and have now identified a phenomenon that explains the effects of oxidative stress on immune cells.
Whenever a foreign body such as a virus or other pathogen enters our bodies, a certain class of immune cells – the T cells – jump into action, proliferating rapidly. One sub-class of these cells, the CD8+ T cells, eliminate the virus by killing cells it has infected. Other T cells, known as CD4+ T cells, coordinate the immune response to all kinds of pathogens. These are the generals in the immune system’s army.
But a week can pass before these T cells start to take their toll on a virus, because in the early stages of an infection too few T cells are able to recognise the specific pathogen. Only once they have had “enemy contact” do these few “scout” cells begin to divide, forming “clones” of themselves. With cells dividing every eight to twelve hours, it takes a few days to gather a strike force of cells in the hundreds of thousands: enough to overwhelm the infection. Continue reading