What is Immune System?
The immune system is the network of cells, tissues and organs that work together to defend the body against attacks by foreign invaders. These invaders are microbes (germs) – tiny infection causing bacteria, viruses, parasites and fungi, cancer cells.
It is the job of immune system to keep them out. In case these invaders find entry in the body, the immune system must destroy them. Complex diseases such as arthritis, cancer or AIDS can occur when the immune system is crippled.
Some of the most important facts about the immune system are:
- It is an extremely complex system.
- It can recognize and remember millions of different enemies.
- To destroy them, the immune system produces secretions (chemicals) that kill and wipe out each one of the enemies.
- The efficient immune system is able to do so because it has an elaborate and dynamic communication network comprising of millions and millions of cells organized into sets, subsets.
- These cells gather like cluster of red ants crowding around an unprotected food article and transporting it to their homes during which they pass information back and forth.
- Once the immune cells receive the alarm, they begin to produce very powerful chemicals. It is most important that these cells receive right alarm at right time.
- Additionally, these chemicals allow cells to regulate their own growth so that they do not grow abnormally to become cancer cells.
What if Immune System Attacks Itself?
For certain reasons, the things can go wrong and the immune system can get significantly crippled. The healthy system has a remarkable ability to distinguish between body’s own cells, self and foreign cells – non self. Body’s immune defenses which include various cells normally co-exist peacefully with other cells that carry distinctive “self” marker molecules. Thus when immune defenders encounter cells or organisms carrying markers that say “foreign”, they immediately launch attack on them so that they can be destroyed. This process is called the immune system response.
Anything that triggers such a response is called the antigen. The antigen can be a microbe or virus or anything such as a cancer cell which immune defenders fail to recognize as own self. However, at times, there are abnormal situations in which the immune defenders fail to recognize body’s own cells. In such a situation, the immune system destroys body’s own cells. In other words the immune system may mistake itself as non self and launch an attack against body’s own cells or tissues. The result is called auto immune disorder. Some forms of arthritis and diabetes are auto immune disorders.
In some cases, the immune system responds to seemingly harmless foreign substance such as ragweed pollens. The result is allergy and this kind of antigen is called allergen. In today’s world we suffer from all kinds of these problems
Components of Immune System
The immune system comprises of
- Lymphocytes in blood: these comprise of T-cells and NK cells – surveillance cells of immune system. They are capable of destroying tumor cells and infected cells.They are the key players in the immune system
- Lymph system which carries these soldiers.
- Lymphoid organs are the battle grounds for lymphocytes. This is extremely important to ensure that the blood circulation system is not required to participate in the battle between the lymphocytes and the invaders. They are strategically positioned throughout the body.
Important Lymph Nodes
The distribution system of the lymph nodes is very complex. The most important lymph nodes are:
- Spleen is a flattened organ located at the upper left of the abdomen. The spleen contains specialized compartments where immune cells gather and work. The spleen serves as meeting ground where immune defenses confront antigens. There are some serious medical conditions that require full or partial spleenoctomy. The persons undergoing full or partial spleenoctomy are required to be extremely careful against various infections
- Tonsils. The tonsils are the first security posts where streptococcus and staphylococcus infections are fought. It is therefore very important to avoid their surgical removal as far as possible.
- Adenoid. Like tonsils, sometimes they are removed surgically. But the price paid is the weakened immune system.
- Appendix. Many people think that appendix has no important function to deliver. This is quite untrue.
- M.A.L.T. (Mucosal Associated Lymphoid Tissue).
Immune cells (lymphocytes) and foreign particles or invaders enter lymph nodes via incoming lymphatic vessels or the tiny blood vessels on the nodes.
All the lymphocytes exit lymph nodes through outgoing lymphatic vessels – once they are in blood stream, they are transported to tissues throughout the body. These are very complex systems.
A few important points which should be noted are:
- One can see the overall spread of the lymphatic system and also the most important nodes. We can see several lymph nodes in abdominal region including diaphragm. The diaphragm plays a major role in enabling the immune system to work efficiently.
- Major vessel is the thoracic duct which begins near lower part of the spine and collects lymph from pelvis, abdomen and lower chest.
- Thoracic duct runs up through the chest and empties into blood through a larger vein near left side of the neck.
- Right lymphatic duct is other major lymphatic vessel and collects lymph from right side of the neck and empties into a large vein near right side.
- Note that while for blood circulation we have heart as a pump, lymphatic system has no pump. The propulsion of lymph has a great influence on the working of body’s immune system.
In the above article, we saw the brief working of the Human Immune System. From the above we can conclude the efficacy of Pranayama Technique in better lymph movement and drainage.