Why Should I Care About My Immune System? — Immunology #1
Have you ever wondered how the body protects itself against viruses and bacteria? Or maybe you’ve seen many articles telling you how to take care of your immune system. But what even is the immune system and how does it work?
If you search ‘the immune system’ on Google or even here on Medium, your screen is filled with articles titled ‘Do This To Improve Your Immune System’ or ‘How To Care for Your Immune System.’
This is all well and good; you should look after your immune system. But, what strikes me is that few people have much of an understanding of what the immune system actually does. If I asked how your immune system keeps you healthy, most people would not know how to answer.
This is a shame because there is not much else that has such a crucial role in your well-being and quality of life as your immune system does. The immune system is an amazing but very complex system that works all day, every day, to keep us alive.
By knowing how the immune system functions you will be able to understand how medications and vaccines work, as well as appreciate the healing process (which can sometimes be a pain, literally).
Over the next few weeks, I’ll be posting a series of articles explaining the basics of the immune system, how it keeps you healthy, and why it is so important to look after it.
In this first article Immunology #1, we’ll go over why the immune system is so important as well as a brief overview of the immune system.
Why is the Immune System Important?
The immune system works all day, every day, to keep you alive and healthy. It protects you from viruses and bacteria that may intrude on your body through cuts, scrapes, or by breathing them in. It also helps to destroy cells gone rogue (such as cancer cells).
If you didn’t have an immune system, you would be susceptible to all kinds of diseases. You would not live very long without major intervention. A famous example of someone who did not have a functioning immune system is David Vetter, also known as The Bubble Boy.
David was born in 1971 and had severe combined immunodeficiency (SCID). This is a genetic disorder in which even pathogens that are essentially harmless to most people can be deadly as the immune system is dramatically weakened. David spent most of his life in a sterile bubble and died of Burkitt lymphoma at the age of 12.
Unfortunately, some people have slightly dysfunctional immune systems. Autoimmune diseases (such as type 1 diabetes or psoriasis), allergies and asthma are examples of this. We’ll get into how this works in future articles.
Important Terminology
Here is a list of some terms that will come up in this article.
What is the Function of the Immune System?
The immune system protects against invading pathogens as well as host-derived damage.
Invading pathogens: Invading pathogens are things such as viruses or bacteria that enter the body when they should not. Common examples of invading pathogens are the SARS-CoV-2 virus that causes COVID-19 or salmonella, the bacteria that cause food poisoning from consuming raw chicken.
There are some bacteria (such as those that live on your skin or in your gut) that have an arrangement with your body in which both you and the bacteria benefit. Yet, even these can become pathogenic if they venture past where they are welcome.
Host-derived damage: Host-derived damage typically refers to your body cells that are no longer healthy, functioning cells. A common example of host-derived damage that your immune system aims to destroy is cancerous or tumor-forming cells.
There are three key points to know about the immune system before we move forward:
The immune system has to be able to distinguish self from non-self. This means that the immune system has to have a method of distinguishing between your body cells (self) and invading pathogens (non-self).
The immune system must be specific and sensitive. The immune system has to be able to recognize unique pathogens. For example, it needs to recognize a specific strain of E. coli rather than recognizing it simply as a pathogen. It also has to be able to detect very low levels of the pathogen.
The immune system has to have redundancy. This means that there has to be multiple pathways within the immune system to achieve the same result. This is important as sometimes a particular pathway can be disrupted.
If a pathway is disrupted, but there is no other route to the destination (the destination being defeating the invading pathogen) then you won’t be able to get there. Redundancy creates a bit of a safety net.
Conclusion
The immune system is vital for keeping you alive and healthy. Without it, you would constantly be unwell and unlikely to live very long.
Here are the key takeaways from this article:
- The immune system is vital for keeping you alive and healthy
- The immune system protects you from pathogens like bacteria and viruses as well as damaged cells such as cancer cells
- For the immune system to work properly it needs to:
- Distinguish self from non-self
- Be specific and sensitive
- Have redundancy
In the next article, we’ll take a look at the four lines of defense that make up the immune system.
