What Is a Lymph Node
You’re probably aware of lymph nodes, and perhaps know that they get swollen when you feel ill. But I bet you didn’t know that lymph nodes are an essential part of your immune system.
In this article, I’ll cover:
- An overview of the lymphatic system, including how the lymph nodes within it fit in to your immune system
- The lymph node’s purpose
- An explanation of the immune cells that are contained within a lymph node
- What kinds of things can damage your lymph system and, thus, your immune system
I know it sounds technical, but bear with me. I’ll keep it basic, and you’ll be glad you discovered this information that’s vital to your health.
An Overview Of the Lymphatic System
Let’s start with the lymphatic system, which is an extension of your circulatory system. Blood flows through your body to your tissues, where some of it is converted into lymph, a colorless fluid containing white blood cells. Lymph then flows through your lymphatic system.
Unlike your circulatory system, your lymphatic system doesn’t have its own pump. Instead, muscular movement causes lymph to circulate through your body, and back into your circulatory system.
Part of the lymphatic system’s function is to serve as a backup drainage system to prevent fluid buildup in your body. This accumulation of fluid is called lymphedema.
But the lymphatic system’s major and most important function is the activation of your immune system, a complex network of cells and proteins that defends your body against infection. If your body is invaded by a pathogen - a microbe that can cause disease- there will be an entire war going on inside your lymph system.
The Purpose Of Lymph Nodes
One purpose of lymph nodes is to contain and hold off a pathogen, such as bacteria and viruses. Your lymph nodes try to prevent the pathogen’s spread throughout your body. For example, you have lymph nodes in your armpit to prevent pathogens from invading your entire arm.
As well, you have lymph nodes in your tonsils at the back of your throat, on the sides of your neck, and throughout your abdomen area into your groin. There are hundreds of lymph nodes in your body. In fact, the largest lymph node is your spleen, which is located on your left side under your ribcage.
With me so far?
Let’s take a look at what’s inside a lymph node.
The Inside Of A Lymph Node
Within a lymph node are immune system cells called lymphocytes. Lymphocytes are cells that carry out their immune function work inside the lymphatic system, although they can go outside the lymph system into other tissues if they’re needed to fight infection.
There are three primary types of lymphocytes:
#1 Natural killer cells
Natural killer (NK) cells are like your special forces. They specialize in killing cells that have become infected with a virus. NK cells kill both the cell and the virus. They’ll also attack tumor cells, such as when you have cancer. This is why sometimes, if you have cancer, your lymph glands swell.
I think people sometimes don’t understand that your immune system isn’t only to fight infection. It also plays a critical role in helping stop the spread of cancer through the body. Yet unfortunately, when someone gets chemotherapy, the chemo itself destroys their immune system, and they end up with secondary infections or a recurrence of the cancer.
The T in T-cells stands for thymus. T-cells have specialized functions aimed at killing specific microbes. They’re essentially trained in their proper function by the thymus. This training is so rigorous that only about thirty percent of cells survive.
T-cells are activated by another immune system called the innate immune system. The innate immune system is one that you’re born with. The cells within it know what to do to mount an immediate, first-line immune defense. But if they need help, they’ll recruit the T-cells, which will then direct additional immune defenses to attack the invading pathogens.
As you can imagine, immune response must be tightly coordinated. Too much, and your body will be damaged. Too little, and the infection will rage out of control.
An essential function of the immune response is to differentiate your body’s own cells from invading cells. There must be a certain tolerance by your immune system of your body’s own tissue; in other words, your immune system has to be trained not to attack your own tissue, including the friendly microbes in your body.
Yet sometimes your immune system goes awry and does end up attacking your body’s own tissues. The result is an autoimmune disease such as rheumatoid arthritis or lupus.
The B in B-cells stands for bone marrow. B-cells make antibodies, which don’t actually kill pathogens. Instead, they tag harmful microbes with an identification; like putting a target on the pathogens. This target helps your body identify and respond more quickly to a subsequent infection by a virus or hostile bacteria.
Antibodies And Lymph Nodes
Antibodies are specific to pathogens. You have an almost unlimited number - trillions - of antibodies. Within the lymph nodes, there are many antibody reactions. Your immune system also takes tiny parts of pathogens and presents them to the T-cells; in effect, the T-cells then can easily recognize and locate the pathogens.
As well, through the lymph node there is substantial lymph/blood exchange. Lymphocytes enter and exit through your tissues all the time. As part of this activity, lymph nodes filter certain cancer cells in an attempt to prevent their spread.
Remember I said the spleen is the largest lymph node? If you’ve had your spleen removed, you’re at a higher risk of infection. And if more of your lymph nodes are damaged or become dysfunctional, your risk increases.
Which begs the question, what causes lymph node dysfunction?
Causes Of Lymph Node Dysfunction
One common reason why people end up with damaged lymph nodes is chronic stress. Chronic stress activates cortisol, which over time shrinks your lymph nodes along with the entire lymphatic system, thus compromising your immune system.
Additionally, if you’re deficient in the trace mineral zinc, you can experience lymphatic system dysfunction. Symptoms of zinc deficiency include apathy, depression, and extensive hair loss.
Ensuring your immune system is robust will go a long way toward you being able to live a long and healthy life. If you’re unsure how to strengthen your immune system, check out my video to help make your immune system bulletproof.
Disclaimer: Our educational content is not meant or intended for medical advice or treatment.
Editor’s Note: This post has been updated for quality and relevancy.