In this series, we explore the true power of the body’s immunity and the organs that work tirelessly to achieve it.

Previously: The spleen protects the body in remarkable ways, so it’s essential to learn how to keep it healthy. 

The thymus is an organ that has puzzled scientists and scholars for centuries. It’s an essential lymphatic organ and an endocrine gland that plays a significant role. Its dysfunction can drastically affect quality of life.

By adulthood, the thymus has significantly decreased in size, so many people think of it as a “shrunken” and “useless” organ. Yet is this really true?

More and more research has discovered that the thymus continues, even into adulthood, to have essential functions across many systems of the body.

The origin of its name is shrouded in mystery. It may come from the plant Thymus vulgaris, better known as thyme, while some research attributes it to the Greek word “thumos,” which can mean “soul,” “courage,” or “will.”

In fact, the ancient Greeks believed that the thymus housed the soul because it was located in the upper part of the chest, just behind the sternum and between the lungs, adjacent to the heart.

The Miraculous Immune System. (The Epoch Times)

The pinkish-gray thymus is well known for its responsibility of directing the development of T cells, which get their name from the thymus, since that’s where they mature—B cells mature in the bone marrow.

The thymus is essential to the immune system, which provides surveillance and protection against pathogens, antigens, and tumors.

T cells are the most powerful adaptive immune cells in the human body and are essential for survival. To destroy T cells is to destroy adaptive immunity, just like the cunning human immunodeficiency virus (HIV) does by hijacking an important subset of T cells first.

Before T cells mature and become full-on specialists capable of fighting the most grueling battles of immunity, they must pass through a life-or-death trial by the thymus.

The thymus is specially designed to train T cells in different “chambers,” where 98 percent of developing T cells will fail and be eliminated. Nevertheless, the thymus still produces enough T cells to protect against every pathogen known to man.

The 2 percent of T cells that successfully pass thymus boot camp are highly trained with specialized roles related to peripheral lymph nodes or other assignments. Careful killers, T cells can effectively distinguish harmful external invaders from healthy human cells.

Dysfunction of the thymus, however, increases vulnerability to infection. Poorly trained T cells also increase the risk of autoimmunity, when the immune system attacks the body.

The thymus is the life-or-death boot camp to combat train T cells. In this diagram, colored cells are alive, and gray cells are dead. Virgin T cells are trained but have not yet come in contact with a live virus or germ. (The Epoch Times)

At birth, the thymus is at its most active, but its workload starts to fall as early as the second year of life. This is because every time the body encounters a pathogen, the thymus trains T cells to deal with it. Once that T cell is matured, it won’t need to be trained again; it simply needs to clone itself.

After the thymus works its way through all the pathogens, it has little left to do. After puberty, it appears to shrink—a process coined “age-related involution or atrophy,” describing how it turns into “useless” fatty tissue.

Despite being shrunken, the thymus is far from useless and plays an important role throughout adulthood.

The thymus is also an endocrine gland that makes active “messenger-like” substances called hormones, which help regulate the immune system and play other functions.

These hormones include thymosin and thymulin, which help make specialized types of T cells; thymopoietin, which fuels T cell production and instructs the pituitary gland to release hormones; and thymic humoral factor, which keeps the immune system functioning well. These systemic functions reflect the varied and vital roles of the thymus.

Beyond stimulating the production of T cells, the different types of thymosin have many other roles.

So far, only two forms of thymosin have been synthesized: thymosin alpha-1 and thymosin beta-4.

Thymosin alpha-1 acts as a multitasking protein and can restore immune system homeostasis in a tailored way based on different health conditions.

The body naturally produces alpha-1, and the synthetic version has been used to modulate the immune system and treat a number of specific conditions, including acute and chronic viral infections such as hepatitis B and C and HIV.

It’s also used to enhance immune function and has been tested against diseases that weaken or dysregulate the immune system, such as cancer and autoimmune diseases.

A distinctive feature of thymosin treatment is that it repairs defective immunity in a balanced way (pdf) without overstimulating cytokine production, resulting in fewer adverse events.

Clinical applications of thymosin alpha-1.(The Epoch Times)

Thymosin beta-4 is an incredible peptide with the ability to develop new blood vessels and help with tissue repair and regeneration.

It also has anti-inflammatory properties, making it an ideal treatment for skin injuries such as burns or cuts.

It can also stimulate the migration and differentiation of cells involved in tissue repair and has even been studied for its potential to promote muscle growth and repair, including in the treatment of cardiac disease.

Recent research suggests that thymosin beta-4 makes some bone marrow cells more sensitive to a growth hormone, which enhances their growth and development into blood cells.

The more we learn about this amazing thymus-originated peptide and related hormones, the more potential benefits are uncovered. As we learn more of the short- and long-term effects of the thymus, we discover how profoundly connected the human body is, hinting at a complicated interplay of hormones, nervous impulses, and immune health.

Clinical applications of thymosin beta-4. (The Epoch Times)

Exciting research has revealed that the thymus produces various hormones that affect growth, metabolism, and brain chemicals. These hormones include insulin, cortisol, and melatonin.

The thymus can also secrete hormones such as T3 under the influence of thyroid-stimulating hormones. Interestingly, studies show that different hormones can regulate each other within the immune system, forming a hormonal network.

Some of its hormones even have anti-inflammatory properties and may help protect against certain cancers.

The thymus can affect the immune, endocrine, nervous, and digestive systems, as well as emotional control. It acts as a vital communication hub, connecting the immune, endocrine, and neurological systems to regulate the body’s functions.

The thymus gland is a remarkable organ that produces hormones that can slow down the aging process. The process is influenced by the pineal gland, which is a tiny endocrinological gland in the brain that secretes melatonin to control the sleep and wake cycles, among other things.

Scientists have discovered a close connection between the thymus gland and the pineal gland, with the potential to unlock more secrets.

The thymus hormones fight aging and help preserve the ability to learn and remember with age.

A recent study published in the journal Nature showed that in pregnant mice, the thymus produces immune cells that are essential for preventing gestational diabetes and miscarriages.

Studies have also shown that defects in the thymus can lead to Type 1 diabetes in animal models.

The thymus is essential for so much in youth, but it still protects the body as it ages, even as it’s shrinking. It still produces T cells important for pregnancy health and immunity and secretes hormones that help to regulate the function of the whole body, including aging and growth. Many of these other roles are only partially understood, and there are certainly other functions that science hasn’t even begun to unravel.

Next: Understanding how to keep the thymus healthy can be a game changer for long-term health.

Read Part 1: The Silent Gatekeepers of Your Immunity Many People Don’t Know Of

Read Part 2: Tonsillectomy: A ‘Minor’ Procedure With Major Long-Term Risks

Read Part 3: Many People Have Removed an Important Body Part, Which May Increase 4 Cancer Risks

Read Part 4: Beyond Detox: Unlocking the Secret Healing Power of the Lymphatic System

Read Part 5: Building a Strong Defense: Boost the Lymphatic System and Detoxify After COVID-19 Vaccines

Read Part 6: Your Miraculous Spleen Works Tirelessly: Cleans Your Blood and Protects Against Viral Assaults

Read Part 7: Beyond the Knife: Warning Signs of an Unhealthy Spleen and 6 Practical Ways to Protect It

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