Tour of Your Immune System Part 1
Over the next few blogs, I am going to give you a tour of the immune system quoted out my book, “The Immune System Handbook”. My hope is that when you get acquainted with how powerful your immune system is, you will support it and allow it to do its magnificent job.
Imagine shrinking yourself down to the size of a tiny cell in order to travel inside your body. Each cell in your body bears a marker that is unique to you. It identifies your cells as “self”. This marker is like a fingerprint that is made up of several molecules in a distinct pattern. No one else’s cells have the same marker, except identical twins. So, as you travel through your body, your immune system recognizes you and you are able to travel as you please. If it doesn’t recognize you, you’ll be attacked.
Our tour will be quick, and you will meet many, but not all characters of the immune system. Because you have had so little concrete experience with your immune system parts, the system may seem a little abstract. Don’t worry. Think of meeting a large contingent of a friend’s family at a family reunion. Unless your memory is exceptional, you will be glad if you can just remember a few faces and names at the end of the day. This tour is designed to “get you into the ballpark”, not to make you a baseball expert.
The body’s first level of defense is the covering: the skin, mucous membranes, and linings of the digestive tract and airways. We have to go past the skin, so we will enter through the mouth or the nose. All the entrances to the body nostrils, mouth, eyes, ears, genitals and anus have their own protective devices.
Before our tour begins, let’s note that the immune system has no single central location in the body, and no chief organ. Instead, it is a cooperative system of biochemicals and white blood cells (leukocytes), tissues and organs which are distributed throughout the body in various locations.
All blood cells, both red and the immune system’s white, are produced in the bone marrow. All blood cells start as a stem cell (a basic building block cell) and develop into groups of more specific secondary stem cells. The secondary cells produce different families of cells, some red and some white. Our tour will focus on the white cells alone, as they make up the immune system.
All white blood cells can be divided into two groups. One of these groups is the “generalists” which respond to general kinds of threats, such as cuts. These are the phagocytes. The other group is the “specialists”. Each respond to a very specific invader; this group is the lymphocytes. These specialist lymphocytes are stored in the spleen, lymph nodes, tonsils, adenoids, appendix, and clusters of lymphoid tissue in the wall of the intestine called Peyer’s patches.
Phago means “eater” or that “which devours”. Phagocytes are particle devouring white cells. Like ravenous Cookie Monsters, they roam the body looking for “invader cookies” to munch on. There are two kinds of phagocytes. One is the macrophage. The others include what I call the “Phil Brothers” neutrophils, basophils, and eosinophils.
As the lymphocytes develop, they divide into B cells and T cells. As they separate, B cells and T cells follow different pathways to populate your body with the various kinds of blood cells it needs. There are two kinds of B cells, and three kinds of T cells. There is some evidence for additional kinds of lymphocytes, such as natural killer cells. (There may be additional cells, but they are yet to be clearly identified and named.)
We will continue this tour in the next blog. If you have any questions or need any immune support, please reach out.
To your good health.