Immune Response

You awake one morning with a stuffy nose at first and throughout the day you start to experience body aches, headaches, coughing and a sore throat. Later you know you will go to the store and get medicine but you’re not too worried because hopefully you will be feeling better in a couple of days. What action is your body taking to get rid of this virus, and how did you even get it in the first place? A virus is a small infectious agent that can replicate only inside the living cells of an organism, and you my friend, are an organism. You can pick up germs anywhere just the head of a pin has the capability to hold up to more than a million germs. Luckily though, we have an immune system which kills the virus.
The immune system has two levels of immunity. The first is called non-specific, also known as innate immunity. This protects the body against foreign material as small as microbes all the way to larger organisms like worms. These organisms are called pathogens when they cause a disease in the host. If a pathogen “breaks the barriers” so to say, white blood cells will surround it and neutralize it. The second level of immunity is specific. This helps the white blood cells if they are unable to stop the pathogen.
There are two types of white blood cells. These are called T and B cells and the human body has millions just for specific antigens. Antigens are a foreign material that triggers a response from the T and B cells. We usually think of antigens as part of microbes but you can receive them just by getting a blood transfusion that did not match your blood type.
B cells mature into plasma cells to produce a protein called an antibody. This protein is targeted to a particular antigen. However, B cells don’t work very well alone so it relies on T cells to provide a signal that they should begin the process of maturation. If the B cell is informed it recognizes the antigen it should respond to and divides to produce plasma cells. These plasma cells then secrete large number of antibodies which fight the antigens.
T cells are activated when the white blood cells display the antigen. T cells can also help release chemicals to help activate B cells, call in white cells for back up to destroy the microbes and even activate killer T cells. These killer T cells recognize the infected cells and destroy them. T cells then recognize that the threat has been removed, and then send out a signal for the rest of the cells to stop attacking.
Killer T cells can also produce memory cells, which remember a specific protein or antigen. The memory assures the body of familiar antigens or foreign agents that have been present in the body within the last few years. A response to an