Everything you need to know about immunology


1.What is immunology?

The term "immunity" is derived from the Latin word "immunis". Immunology is a biomedical science that studies organisms' immune responses to antigenic substances as well as the methods used to study them. Immune response is the body's reaction to antigenic stimulation, as well as a biological process that identifies and eliminates antigenic substances.

Recognizing "self" and "non-self" antigens, forming natural immune tolerance to self-antigens, and rejecting "non-self" antigens are all physiological functions of the body. Under normal conditions, this physiological function is beneficial to the body and can produce immune protection effects such as anti-infection and anti-tumor to keep the body's physiological balance and stability. When the immune system malfunctions under certain conditions, it can cause harmful reactions and outcomes in the body, such as hypersensitivity, autoimmune diseases, and tumors.



2.The history of immunology

Immunology is both an old and new science. It is widely assumed that the evolution of immunology has occurred in four stages:

Period of experience

Chinese medical scientists creatively invented human vaccinia in practice as early as the 11th century AD, that is, to prevent smallpox by artificial mild infection.


Classic Period

Classical immunology existed from the 18th century to the middle of the twentieth century. People's understanding of immune function entered the period of scientific experiments based on observations of human body phenomena during this period.


Modern times

The period of modern immunology lasted from the middle of the twentieth century to the 1960s. During this time, people broke free from the anti-infection immune template theory and gained a more comprehensive understanding of organisms' immune reactivity, allowing immunology to begin studying biological issues and a new immunology theory to emerge.


Modern period

The term "modern immunology" refers to the period between the 1960s and the present. During this time, the role of lymphocytes in the immune response was confirmed, the molecular structure and function of immunoglobulins were clarified, and numerous studies on the immune system, particularly cytokines and adhesion molecules, were conducted at the molecular level. The diversity and class conversion of immunoglobulins have been discussed in depth, and significant advances have been made in a variety of areas.



3.What exactly is immune disease?

Immunological diseases are caused by an imbalance in immune regulation, which affects the body's immune response. Immunological diseases, in a broad sense, also include immune system structural or functional abnormalities caused by congenital or acquired causes. Among these are autoimmune diseases, which are diseases caused by the immune system's immune response to its own body's components, causing damage. Some abnormalities appear in the tissue components of the body or the immune system itself as a result of certain factors, causing the immune system to mistake its own components for foreign objects to attack.At this point, the immune system will produce antibodies against some of the body's own components as well as active lymphocytes, causing damage and destruction to its own tissues and organs, leading to diseases such as rheumatoid arthritis, systemic lupus erythematosus, Sjogren's syndrome, ankylosing spondylitis, and others.According to data, the prevalence of rheumatoid arthritis in my country is 0.24-0.3%, with women outnumbering men by about 2-3:1. It can occur at any age, with 40-60 years old being the most common. Rheumatoid arthritis is a chronic autoimmune disease characterized primarily by joint lesions and recurrent attacks. It begins with joint swelling and pain, then progresses to cartilage destruction and joint space narrowing. It can cause joint stiffness, deformity, dysfunction, and a high disability rate in the later stages.


The emergence of monoclonal antibody technology in recent years has been a major breakthrough in the field of immunology. Monoclonal antibodies can detect various immune cells and other tissue cell surface molecules, which is important for immune cell separation, identification, and classification, as well as the study of the structure and function of various membrane surface molecules.

After recombinant protein, monoclonal antibodies are an important part of biomedicine. It has broad application prospects in disease treatment and has been successfully used in the treatment of various diseases such as autoimmune diseases and tumors, becoming the most important biopharmaceutical product category, such as fully human monoclonal antibodies for rheumatoid arthritis.



4.How Does the Immune System Function?

When the body detects foreign substances (called antigens), the immune system works to recognize and eliminate the antigens.


B lymphocytes are stimulated to produce antibodies (also called immunoglobulins). These proteins bind to particular antigens. Antibodies typically remain in our bodies after they are produced in case we need to fight the same germ again. That is why, once a person becomes ill with a disease, such as chickenpox, he or she is unlikely to become ill again.


Immunizations (vaccines) work in the same way to prevent some diseases. An immunization exposes the body to an antigen in a way that does not cause illness. However, it allows the body to produce antibodies that will protect the person from future germ attacks.


Although antibodies can recognize and bind to antigens, they cannot destroy them on their own. That is the function of T cells. They destroy antigens that have been tagged by antibodies, as well as infected or altered cells. (Some T cells are referred to as "killer cells.") T cells also assist in signaling other cells (such as phagocytes) to do their jobs.




Antibodies can also:


Toxins (poisonous or harmful substances) produced by various organisms activate a group of proteins known as complement, which are part of the immune system. Complement aids in the killing of bacteria, viruses, and infected cells.

These specialized cells and immune system components protect the body from disease. This is referred to as immunity.


There are three types of immunity in humans: innate, adaptive, and passive.


Innate immunity: Everyone is born with innate (or natural) immunity, which serves as a type of general defense. For example, the skin acts as a barrier to keep germs out of the body. Furthermore, the immune system recognizes when certain invaders are foreign and potentially dangerous.

Adaptive immunity: We develop adaptive (or active) immunity throughout our lives. When we are exposed to diseases or are immunized against them with vaccines, we develop adaptive immunity.

Passive immunity is "borrowed" from another source and only lasts for a short time. Antibodies in a mother's breast milk, for example, provide a baby with temporary immunity to diseases to which the mother has been exposed.

Vaccines aid in the development of the immune system, which takes time. By ensuring that your child receives all of the recommended vaccines on time, you can help keep your child as healthy as possible.





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