We all know about the immune system. It fights off colds and flues and infections! It protects us from “foreign invaders”, and it runs on vitamin C and Echinacea! The immune system keeps us healthy.
But for millions of people the immune system is no white knight. According to current estimates of the National Institutes of Health, 23.5 million American citizens alone have what are called “autoimmune” diseases. These are chronic conditions caused by a glitch in the immune system (yes, the very same one that fends off colds and flues), which leads the system to attack specific cells in the body as if they were foreign.
Some of the conditions we owe to this dastardly biological misstep bear familiar names: psoriasis, diabetes, rheumatoid arthritis. Others less so: scleroderma, Grave’s disease, Hashimoto’s thyroiditis. They include problems with the digestive, endocrine and nervous systems, blood, skin, connective tissue, muscle, bone and more. All in all, roughly 100 serious diseases result from our very own immune systems, and because these systems stay with us through our lives, the diseases they cause do, too.
…Which brings us to the question I posed last Thursday: “why do autoimmune disorders pose a special challenge for stem cell researchers?” in my article entitled “UCSF Opens New Center for Regenerative Medicine”.
To recap: scientists are optimistic that stem cells can be used to treat a variety of autoimmune diseases by replacing the cells attacked in the autoimmune response with cells grown in a laboratory. Attentive readers are thinking: “but earlier we agreed that the immune system attacks foreign invaders, which lab-grown cells are, so we already know this won’t work.”
Good thinking, but of course stem cell researchers already thought of that, and a great deal of research has and does go into the quandry of “hiding” foreign cells from the immune system. For our purposes in Autoimmunity 101, however, that’s not the most interesting challenge.
The most interesting challenge, in my opinion, is this: if your immune system thought cells in your thyroid, for example, were foreign, and attacked them, then if you replace them with more thyroid cells the very same thing will happen again. Thank you, immune system, for fighting off that flu, healing that cut, and blowing up my (insert your system of organ of choice)!
Researchers are working on a variety of extremely complicated remedies for this pernicious situation, and some of the most high-powered research is happening right here in San Francisco, at UCSF.
Stay tuned for “how to trick a tricky immune system”.