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  5. Immune System Explained: Cells, Tissues and How It Works?

Concerns regarding immunity have become all the more important owing to the COVID-19 outbreak. Many of you have been ingesting immunity boosters like never before to stay healthy and fit amid the pandemic.

But have you thought how a large number of people are surviving the novel coronavirus? And why is it not attacking them again? On the whole, it is the immune system that is doing a remarkable job of combating disease-causing microorganisms.

In this article, we shed light on the natural defense mechanism of your immune system.

What Is Immune System?

The immune system in a human body is an intricate, co-dependent structure of organs, tissues, cells, networks and protein molecules. It is a defense mechanism to fight disease-causing organisms in your body. It acts as a firewall to protect the body from the entry of potentially harmful elements. [1]

When your body senses foreign substances/antigens, the immune system works to recognize the antigens and get rid of them.

Ayurveda defines immunity as your body’s capacity to fight against the manifested diseases and to resist the pathogenic process of forming diseases. The modern concept of immunity is quite closer to the principles of Ayurveda.

Dr.Zeel Gandhi, Chief Ayurvedic Doctor at Vedix, says, “In Ayurvedic perspective, Bala (strength) and Vyadhi Kshamathwa (resistance to disease) are the two important components of your immune system. Factors contributing to immunity are balance of doshas, health of the seven tissues (plasma, blood, muscle, fat, bone, nerve, and reproductive tissue), normal levels of agni. Patency of the channels in the inner transport system of your body such as circulatory and respiratory systems or factors supporting the equilibrium state of all the physiological parameters also play a big role.”

Types Of Immune System

Everyone has a different immune system; however, it is said to become stronger during adulthood. This is the time when your body gets exposed to more pathogens and develops immunity.

Read on to know the different types of the immune system.

1. Innate Immunity

Natural immunity or innate immunity is the first defense line in your immune system. It can recognize general threats and readily attacks foreign elements with an inborn primary defense mechanism. Innate immunity is correlated to the Sahaja Bala described in Ayurveda. It is your body’s constitutional strength that exists in your mind and body right from your birth.

2. Adaptive Immunity

Acquired immunity or adaptive immunity is the second defense line. If the innate immunity is about to lose the war with the pathogen, the immune system activates adaptive immunity.

Kalaja and Yuktikrita Bala are related to acquired immunity. It is acquired by the combination of diet and physical activities. It is of two types:

3. Active Immunity

Active immunity involves the process of exposing the body to an antigen to generate an adaptive immune response. It learns the threat and designs a strategic response to kill the pathogen by manufacturing antibodies.

It consists of immunological memory cells to remember the structure of the pathogen and the type of risk. Whenever the pathogen re-enters your body, adaptive immunity recognizes it immediately and attacks it quickly.

Active immunity is also acquired through vaccination. A vaccine is prepared using mild synthetic substances of a pathogen, which your body never encountered. When infused into your body, it triggers the production of antibodies against it.

If the natural form of the same pathogen or its related organisms enter your body anytime later, the antibodies are ready to fight it.

4. Passive Immunity

This type of immunity is borrowed from another source typically when a person is unable to produce antibodies through his or her own immune system.

Passive immunity happens naturally when newborns receive mother’s antibodies through the placenta or breastmilk and artificially when a person receives antibodies in the form of an injection.

A healthy person can donate antibodies to a diseased person depending on the cause and suitability. It is purposeful in an emergency and diminishes in a short period.

The plasma or the plasma-B cells are white blood cells that produce large quantities of antibodies when exposed to a pathogen. Antibodies not only kill the pathogen but also builds resilience to its re-entry.

The survivor's plasma contains antibodies to treat the disease. It is why a survivor's plasma is donated to a victim whose immune system is weak to produce antibodies. [2]

Word Of Caution: Avoid taking excess immune boosters without a doctor's advice. It may have a detrimental impact on your immune system in the long run.

illustration of acquired immunity

How Does The Immune System Work?

The immune system is an elaborated dynamic communication network. It organizes millions of cells into sets and divides them into subsets to recruit them in different places of your body. It remembers millions of foreign elements that invaded your body right from your birth. As soon as it recognizes a threat, it builds a fighting force to sweep off the enemies out of your body.

The groups of cells communicate like an army of soldiers to pass information back and forth. Once they receive an alert, they undergo tactical changes and start secreting potent chemicals. These substances allow the cells to regulate their line of defense, targeting the trouble spots. [3]

1. Self & Non-Self

An antigen is a protein molecule on the surface of an organism and is a part of it. It can spark an immune response. The convention antigens in your body are self-antigens and the ones that do not originate from your body are the non-self-ones.

The immune system needs to be able to distinguish between self and non-self. It does this by detecting proteins on the surface of all cells. It learns to ignore its own or self-proteins at an early stage.

If a pathogen enters your body, the antigen attached to it makes a call-to-action that triggers your immune system to release antibodies against it.

The immune system's ability is its great consciousness of 'self' and 'non-self' elements in your body. It can identify and distinguish between right and wrong visitors into your body. If the army of cells gets a notification of any organisms that have non-self marked antigens, they immediately launch a battle. [4]

2. The Lines Of Defense

When a pathogen tries to infect your body, the immune system releases chemicals to increase body temperature. It helps to stop the growth of pathogens and speed up immune response.

A. Skin is the outermost barrier to secrete immune cells and prevents harmful substances into your body.

B. Tonsils and adenoids are present at the very back of the nasal passage and your throat. They catch hold of the pathogen in this route and release antibodies to kill it before it infects your throat and lungs.

C. Mucous membranes are attached to the outlines of digestive and respiratory tracts, and urogenital passageways. They secrete mucus. The mucus traps the germs and leads them to death.

D. Stomach acids and antibacterial actions in your intestines kill the pathogen as soon as it enters the digestive tract.

E. If the pathogen still penetrates deeper into your body, B cells and T cells are triggered to understand the threat and manufacture antibodies to kill the pathogen.

Vedix Tip: Prepare a decoction by boiling tulsi, pepper, and ginger. Replace your tea with this herbal tea to improve your immunity.

human anatomy of immune system

What Are The Parts Of The Immune System?

The immune system is found throughout the body and is made up of many different cells, organs, and tissues. The organs and tissues of the system can be classified as lymphoid organs. Each organ is a home of lymphocytes (white blood cells). White blood cells or WBC play a key role in preventing our body from the attack of foreign invaders.

The important parts of the immune system are:

1. The Lymphatic System

Lymphocytes travel in your body through blood vessels and lymphatic vessels. Lymphatic vessels are located parallel to the blood vessels- the veins and the arteries. Blood vessels and lymphatic vessels exchange information with cells and fluids, making the lymphatic system aware of the foreign invaders.

Lymphatic vessels or tubes carry a clear fluid called lymph to clean the tissues. Lymph nodes are small in size of 1mm to 25 mm, laced along the lymphatic vessels with clusters in specific parts of your body. They have special compartments to filter foreign particles with the help of immune cells.

2. Bone Marrow

The hollow space in the bones contain a soft tissue. It is the source of all blood cells, including the two categories of WBC- B cells and T cells. It makes millions of blood cells every day and releases them into your bloodstream. B cells are produced and matured in the bone marrow ( B refers to the bone marrow).

3. Spleen

The spleen is a broad and flattened lymphoid organ located behind the stomach, storing white blood cells and other blood cells. Its primary function is to filter red blood cells and platelets by destroying the old and damaged cells. It serves as a compartment where immune cells confront antigens.

4. Thymus

Thymus is located right behind the chest bone where the white blood cells mature. They are called T-cells, where T refers to Thymus. T cells directly kill infected cells, activate other immune cells, and regulate an immune response. [5]

Vedix Tip: Add turmeric, black pepper, jeera, methi, curry leaves, garlic, and ginger to the food you eat daily. It supports your immune system.

What Are The Functions Of The Immune System?

There are three main functions of the immune system. They are:

1. Mounting immune response to fight disease-causing pathogens that enter your body.

2. Store information in the immunological memory to recognize and neutralize harmful elements from the environment.

3. To combat the changes in your body caused by an infection or a disease such as cancer cells.

Wholehearted laughter for at least twenty minutes a day releases dopamine and uplifts the strength of your immune system.

The Last Word

The immune system has a vital role to play to protect our body from various disease-causing viruses and bacteria. Without a healthy immune system, we would be frequently falling sick. With regular exercise, good diet and healthy lifestyle, we can help our immune system work in good order.

Know Your Dosha Now