The thymus gland plays a key role in the maturation of T-cells during childhood and adolescence. When a program is active, it can be found on top of the endocrine glands, but will eventually migrate to the thoracic cavity or chest cavity afterwards.
Allergic diseases or congenital immunodeficiency may lead to atrophy, whereas cancer will lead to enlargement. Thus, the thymus is an important indicator to reflect our immunity.
Do you know which lymphoid organ is primarily active during the early years of life? If not, Check out here!
The thymus gland, one of our immune organs, is situated on both sides of the heart and anterior to the sternum. It is important in the maturation of T-cells and its activity balances the overall immune system.
The thymus will gradually shrink during childhood and adolescence due to poor nutrition or other factors such as frequent infections, etc. In Chinese medicine, it has been called “the emperor of two Yuan” for a long time. The “two Yuan” refers to mind and spirit (shen) as well as the immunity system (Yuan Qi).
Here some points are discussed-
1. Early life is the formative period for the thymus gland.
A well-developed thymus will be a good protector in later years, whereas an under-developed one may lead to vulnerability towards any serious infection. Immunity is influenced by both genetic and environmental factors.
In today’s fast changing society, childhood nutrition is less than ideal and infections are more common, thus causing shrinking of the thymus gland at an early age. Additionally, allergic reactions and frequent infections could also lead to certain immunological changes even before the child suffers from any diseases such as asthma or eczema.
2. Thymic size is an important indicator for the immune system.
It can be used to reflect our immunity and serves as an excellent index for assessing the overall health status. Children with thymus gland hypertrophy are more likely to have a better immunity and less likely to suffer from any allergies.
On the other hand, those with smaller thymus will be vulnerable to immune deficiencies and allergies later in life. A pilot study showed that when children were given herbal treatment, their thymic size improved significantly after 1-5 months of treatment, suggesting that herbs would help them improve their overall immunity as well as allergy conditions.
3. The thymus gland plays a role in the maturation of T-cells.
Since childhood years, it has been considered as a key regulator of our immune system. According to studies on mice, the thymus is involved in ontogenetic development and maturation of T-cell immune response against virus infection.
It develops and differentiates into two distinct cell populations with different functions: cellular ones (CD4+ and CD8+) for generating CD4+ helper T-cells and non-cellular ones (CD4− CD8−) for generating CD8+ cytotoxic T-cells which are critical for antiviral immunity.
The cellular component of the thymus is critical for regulating T-cell proliferation, maturation and effector functions. In other words, proper development of T-cells requires the thymus. The functions of non-cellular components remain unclear.
4. The thymus gland shrinks during childhood and adolescence.
In some cases, allergies may lead to atrophy of the thymus. A study on infants in Macao showed that children with atopic dermatitis tend to suffer from atrophy of the thymus, whereas those with non-atopic dermatitis do not show such changes.
The size of the thymus is associated with atopy outcome (atopy is a form of allergic rhinitis) and susceptibility of developing major infections later in life. Those who do not suffer from allergies or infections early in life may have better immune systems and a normal sized thymus gland. However, children who are frequently infected with bacterial or viral infections may lead to shrinking of the thymus.
5. A smaller thymus is associated with a variety of diseases.
Allergic rhinitis is one of the most common conditions in childhood. Children with smaller thymus are more likely to suffer from allergies as well as develop coronary heart disease or certain types of cancer.
Those with smaller and atrophic thymi tend to have more severe symptoms when infected with a virus and have a poorer prognosis following respiratory viral infections than those with normal size glands. It has been suggested that an under-developed thymus may be due to premature aging process or failure to sustain normal levels of growth hormone during early years of life.
6. The thymus shrinks because nutrition is poor.
Thymic atrophy is closely related to malnutrition in childhood. A study into the relationship between malnutrition (underweight) and immune system in childhood showed that many children suffered from malnutrition because of fertility and medical conditions such as cancer.
Thymic size was much smaller in underweight children than those with normal weight, implying that normal weight may be the ideal condition for proper growth of the thymus gland during early years of life.
