The topic of this week’s blog is on the two-faced, backstabbing diseases of the microbiology world. What are these treacherous diseases you ask? Well, they are none other than autoimmune diseases. As the name suggests, these diseases occur when immune cells begin to attack host tissues they are supposed to be protecting. Rude. This is where the backstabbing reputation comes from. You expect your immune cells to protect be there for you through thick and thin, but instead they attack you. You wonder who will be there for you; who can you trust?
Have no fear, therapy is here! Therapy is our knight in shining armor when it comes to saving us from the evil autoimmune diseases. Earlier I gave a very generalized description of an autoimmune disease. I think it’s important to give a little more background on what kinds of diseases can arise before diving into how therapy can be used. According to the American Autoimmune Related Disease Association, there are more than 100 autoimmune diseases, so I will not be discussing all of them. Among the numerous autoimmune diseases are Lupus, Narcolepsy, Psoriasis, and cancers. It is reported that about 75 percent of autoimmune disease cases occur in women. What’s so scary about these types of diseases is that the cause is sometimes not fully understood. However, it is thought that some cases are triggered by exposure to microorganisms in people who have a genetic predisposition to the disorder. Now that you have a better idea on what an autoimmune disease is, we can look at what we can do to treat them.
This article discusses both current practices and future prospects for treating autoimmune diseases. Most traditional therapies rely on immunosuppressive medications that aim to dampen immune responses. These have shown great promise in helping patients and are the current chosen option of care when it comes to treating autoimmune diseases. Unfortunately, when these medications are used for long periods of time, high doses are needed to maintain disease control. This can cause the patient to become vulnerable to other deadly opportunistic infections. Since this type of therapy can have serious consequences there has been a push for development of new therapies to treat autoimmune diseases with lower risk of other infections.
One of the new wave treatments is a costimulatory blockade. This type of therapy deals with the activation of T cells. T cells require two main signals in order to become activated. The first signal is antigen recognition through a T cell receptor by major histocompatibilty complex (MHC) molecules on antigen presenting cells (APC). The second signal is a costimulatory signal where ligand B7 on APC interacts with the CD28 receptor on T cells. Both of these signals are needed to achieve full activation, so if one of these signals is not present then the cell will become anergic. This means there will be a lack of immunity to that specific antigen. By blocking this costimulatory pathway we can inhibit the activation of auto-reactive T cells in patients with autoimmunity and voilà! We have a new therapy to treat autoimmune diseases.
The Fascination with Vaccination 