Recently, I had the opportunity to experience the remarkable actions of my immune system. Having been “gifted” by one of my patients with a rousing upper respiratory infection, I was reminded of the many mechanisms of the body that work to keep me healthy. I saw this patient again after we had both recovered, and we laughed together and shared that it was wonderful that neither of us would likely be affected by this virus in the future. That is because of the marvelous mechanisms of our immune systems.
Our immune system is designed to protect us from harmful bacteria, microbes, viruses, toxic substances, parasites, and helminths (worms). Without our immune system, we would be invaded by numerous organisms that would break us down cell by cell and leave us as a skeleton. Eventually the bones themselves would be broken down, too.
Our immune systems never sleep and are mind-boggling in their complexity. Two full-semester courses are dedicated to the immune system during medical school. During the first semester, medical students learn about the normal workings of the immune system mechanisms (fever, hives, inflammation, infections, antibodies, vaccinations, etc.) and the second semester, they learn about how it goes awry. Despite this intensive study, there are many aspects about the immune system that we have yet to understand and, hopefully, eventually harness for our greatest good.
The skin is your first defense. It consists of multiple layers that protect against the invasion of bacteria and other pathogens. Its job is to recognize invaders and close off wounds. Inflammation (such as a red bump around a mosquito bite) and the formation of pus (immobilizing the pathogen) are visible effects of your immune system in action.
Your next layer of defense is the linings of your body cavities and pathways, and the components that live there. Some examples: your ears and nose use wax and secretions and small hairs to catch particles, your sinus cavities trap unwanted particles or pathogens giving your body a chance to tackle them before they cause illness or infection, your saliva is hostile to several pathogens, your stomach acid is a potent agent for killing undesirable pathogens in your food or water, and your stool is an excellent eliminator. Some pathogens are so potent, that the body immobilizes them rapidly via vomiting or explosive diarrhea—have you ever thought to say “thank you” for those mechanisms!
Once an organism gets past your initial defenses, other mechanisms become activated. The most common organisms are bacteria and viruses. Bacteria are living organisms that feed on nutrients in your body and then reproduce. Viruses are not living organisms. They place a fragment of their DNA into your healthy cells. Your cells then act as factories that do the “dirty work” for the viruses by replicating them.
Some of you may think that your immune system isn’t working well because you get sick often, or you have a lot of allergies. In actuality, this is NOT because your immune system isn’t working, but it is working too much and perhaps has become too reactive. Autoimmune system disorders are the result of the immune system working improperly, almost like a short-circuit in a light fixture. When the switches should be off, they continue to send signals. Some examples of this are type 1 diabetes, wherein the body attacks its own pancreatic beta cells, rheumatoid arthritis, wherein the body attacks its own joints, and thyroiditis, wherein the body attacks its own thyroid cells. These are immune system errors. While we understand how these conditions affect the body, and often have treatments that slow the processes, we do not have a clear understanding of exactly why these conditions initially occur or how to reverse the underlying mechanisms that initially triggered the immune system malfunction. We do know that many factors are involved: nutrients, genetics, environmental factors, damaged or unhealthy organs, and others.
Your major immune system players are (take a deep breath): your thymus (located very near the heart), your spleen (located under the left ribs), your lymphatic system, your bone marrow, your white blood cells (lymphocytes, monocytes, granulocytes, B-cells, plasma cells, T‑cells; helper T-cells, killer T-cells, suppressor T-cells, natural killer cells, neutrophils, eosinophils, basophils, phagocytes, and macrophages—whew), your antibodies, your complement system (made in the liver and “complement” your antibodies), your hormones (many!), tumor necrosis factor (able to kill tumor-like cells), interferon (“interferes” with viruses), and your Major Histocompatibility Complex (MHC, also called Human Leukocyte Antigen or HLA) that identifies the cells in your body as being “you.”
Vaccinations are designed to “prime” our immune system. For several diseases, once the body has been exposed to and handles the disease, it does not recur, for example, mumps or measles. The B-cells are able to recognize the pathogen and eradicate it before it can multiply and cause disease. Vaccinations contain a very small amount of a disease-causing pathogen in either a live or inactivated form. They trigger the same response as the disease, but because the vaccine is so much weaker than the actual disease, minimal symptoms occur. If there is exposure to the actual disease in the future, the body handles it very quickly.
When a bacterial infection appears to be overwhelming the immune system, antibiotics will often be prescribed. These medications are either bacteriocidal—able to kill the bacteria, or bacteriostatic—able to slow the reproduction of the bacteria to give the body a chance to catch up and contain the infection. Antibiotics are NOT effective against viral infections.
Over time, antibiotics can lose their effectiveness, especially if they are used too often. Because of this, a major issue we are facing today is antibiotic “resistance.” Because bacteria are living organisms, they change over time and can become able to resist the effects of certain antibiotics.
Supporting your immune system is challenging. It is a complicated system with many components. This list from Harvard Medical School is a good start (with my embellishments added):
- Don’t smoke.
- Eat a diet high in fruits and vegetables.
- Exercise regularly.
- Maintain a healthy weight.
- If you drink alcohol, drink only in moderation.
- Get adequate sleep.
- Take steps to avoid infection, such as washing your hands frequently and cooking meats thoroughly.
- Work to minimize stress. Finds ways to laugh and enjoy life.
- Have regular check-ups with your doctor.
- Clear your ‘stuck’ emotional energies.
- Be grateful for your immune system!
© Trinity Integrative Family Medicine, glkocourek, Nov-2018, latest revision 09-May-2021