How does the immune system work?

A human body is the best creation of Mother Nature. It is able to reproduce, think, imagine, envision, dream, multi-task, and outperform any other creature on the planet. One of the amazing features it possesses is the immune system. As it is evident from the term itself, the immune system is responsible for protecting the human body against viruses and infections. It is a complex system that makes use of cells and different techniques to tackle the virus and germs of different types. Even though the immune system is working round the clock to ensure that the human body is free of potentially harmful bacteria and viruses, it shows its efficiency and extreme power when it comes to face to face with a virus it does not recognize.

The immune system becomes activated and starts to perform as soon as it detects something that is not familiar to itself. There are a lot of things that could trigger an immune system. Antigens are one such example. Viruses, bacteria, and fungi have protein on their surface and are a good example of antigens. The immune system in the entire body gets triggered when these antigens attach themselves to the immune cells. Upon initially coming up with the germ that will cause the diseases, the body stores information about it and how to fight it. In this way, if the germ comes in contact with the body again, the body will fight back more aggressively this time.

The body’s cells have proteins on their surface as well. However, they do not trigger the immune system every time. Sometimes the immune system may mistakenly think of its own cells as foreign cells and start eating and fighting healthy cells.

Contrary to the belief that there is only one immune system; in reality, there are two sub-systems within an immune system. These are known as the innate and adaptive immune systems. Both of these systems come together to fight and tackle the harmful germ that will potentially cause disease. The innate immune system is the body’s primary source of general defense as it uses immune natural cells and phagocytes. The main responsibility of the innate immune system is to fight the germs that make their way into the body through sources such as the skin and digestive system etc.

The adaptive immune system, on the other hand, creates antibodies and uses them to fight the germs and viruses that have come in contact with the body earlier as well. Furthermore, there is another type of immunity, which is known as Passive immunity. Passive immunity takes place due to antibodies that are produced in a body other than your own. For instance, infants have antibodies that are transferred through the mother via breastfeeding or placenta. As the child reaches a 6 to 12-year mark, these antibodies disappear. The purpose of these antibodies is to protect the child when his/her body, particularly the immune system, is not mature enough to defend the body against germs. Over time as the child grows, the immune system grows, which as well allows it to produce its own antibodies to fight against harmful substances.