What is Immunology? | British Society of Immunology (2023)

Why is immunity important?

From Edward Jenner's ground-breaking work at 18^mcentury that would eventually lead to vaccination in its modern form (an innovation that probably saved more lives than any other medical advance), to the many scientific discoveries of the 19th century^mat 20^mcenturies that would lead to, among other things, safe organ transplantation, the identification of blood groups, and the ubiquitous use of monoclonal antibodies in science and health care, immunology changed the face of modern medicine. Research in immunology continues to expand our understanding of the treatment of major health problems, with ongoing research efforts in immunotherapy, autoimmune diseases, and vaccines for emerging pathogens such as Ebola. Increasing understanding of basic immunology is essential for clinical and commercial application and has facilitated the discovery of new diagnostics and therapies to treat a wide variety of diseases. In addition to the above, immunological research coupled with advanced technology has yielded critical research techniques and tools such as flow cytometry and antibody technology.

What is an Immunologist?

An immunologist is a scientist and/or clinician who specializes in immunology. Many immunologists work in a research-focused laboratory, either in academia or in the private sector (for example, the pharmaceutical industry). Other immunologists -- "clinical immunologists" -- are clinicians who focus on diagnosing and treating diseases of the immune system, such as autoimmune diseases and allergies.

For more detailed information on careers in immunology, see our pagecareer department.

The immune system

The immune system is a complex system of structures and processes that evolved to protect us from disease. Molecular and cellular components make up the immune system. The operation of these elements is broken down into non-specific mechanisms, which areCongenitalin an organism, and responsive responses, which arecustomto specific pathogens. Basic or classical immunology involves the study of the components that make up the innate and adaptive immune systems.

Innate immunityit is the first line of defense and is not specific. That is, the responses are the same for all possible pathogens, however different they may be. Innate immunity includes physical barriers (eg skin, saliva, etc.) and cells (eg macrophages, neutrophils, basophils, mast cells, etc.). These components are "ready to use" and protect an organism during the first days of infection. In some cases this is enough to destroy the pathogen, but in other cases the first defense is overwhelmed and a second line of defense is initiated.

Adaptive Immunityit is the second line of defense that consists of building up memories of infections that have been dealt with so that an enhanced response specific to the pathogen or foreign substance can be generated. Adaptive immunity involves antibodies, which generally target foreign pathogens that circulate freely in the bloodstream. Also involved are T cells, which specifically target pathogens that have colonized cells and can kill the infected cells directly or help control the antibody response.

Immune dysfunction and clinical immunology

The immune system is a highly regulated and balanced system and when the balance is disturbed disease can result. Research in this area involves the study of diseases caused by malfunctioning of the immune system. Much of this work is important to the development of new treatments and therapies that can control or cure the condition by changing the way the immune system works or, in the case of vaccines, activating the immune system and modifying the immune response to specific pathogens. stimulation. .

ImmunodeficiencyDisorders refer to problems with the immune system that impair the ability to mount adequate defenses. As a result, they are almost always accompanied by severe infections that persist, recur, and/or lead to complications, making these conditions severely disabling and even fatal. There are two types of immunodeficiency disorders: primary immunodeficiencies are typically present from birth, are generally inherited, and are relatively rare. One such example is common variable immunodeficiency (CVID). Secondary immunodeficiencies generally develop later in life and can result from infection, such as AIDS after HIV infection.

Autoimmuneillnessesthey occur when the immune system attacks the body it is supposed to protect. People with autoimmune diseases have an abnormality that prevents them from distinguishing "self" from "non-self" or "foreign" molecules. The principles of immunology have led to a wide variety of laboratory tests for the detection of autoimmune diseases. Autoimmune diseases can be described as "primary" autoimmune diseases, such as type 1 diabetes, which can manifest from birth or early in life. or as "secondary" autoimmune diseases, which manifest themselves later in life due to various factors. Rheumatoid arthritis and multiple sclerosis are thought to belong to this type of autoimmunity. Autoimmune diseases can also be localized, such as Crohn's disease affecting the gastrointestinal tract, or systemic, such as systemic lupus erythematosus (SLE).

allergiesare hypersensitivity disorders that occur when the body's immune system reacts to harmless foreign substances, causing the body's own tissues to be damaged. Almost any substance can cause allergies (an allergen), but allergies usually develop after eating certain foods, such as peanuts, or by inhaling airborne substances such as pollen or dust. In allergic reactions, the body thinks the allergens are dangerous and immediately produces substances to attack them. This causes immune system cells to release powerful chemicals, such as histamine, that cause inflammation and many of the symptoms associated with allergies. Immunology tries to understand what happens in the body during an allergic reaction and the factors responsible for causing it. This will lead to better methods for diagnosing, preventing and managing allergic diseases.

Asthmais a debilitating and sometimes fatal respiratory disease. It usually occurs when the immune system reacts to inhaled particles from the air and can lead to thickening of the airways in patients over time. It is a major cause of illness and is particularly common in children. In some cases it has an allergic component, but in some cases its origin is more complex and poorly understood.

Canceris a disease of abnormal and uncontrolled cell growth and proliferation and is defined by a number of characteristics, including the ability of cancer cells to evade immune destruction. Knowing that evading the immune system can contribute to cancer, researchers have turned to manipulating the immune system to defeat cancer (immunotherapy). Cancer immunotherapy seeks to stimulate the immune system's innate powers to fight cancerous tissue and has shown great promise as a new weapon in our arsenal against disease. Other applications of immunological knowledge in cancer include the use of monoclonal antibodies (proteins that seek out and bind directly to a specific target protein, called an antigen. One example is Herceptin, a monoclonal antibody used to treat breast and stomach cancer ). In addition, a number of successful cancer vaccines have been developed, most notably the HPV vaccine.

Transplantsthe transfer of cells, tissues or organs from a donor to a recipient. The most formidable obstacle to transplants is the immune system's recognition of transplanted organs as foreign. Understanding the mechanisms and clinical features of rejection is important for diagnosis, treatment advice, and is critical for the development of new strategies and drugs to treat grafts and reduce the risk of rejection.

Vaccinesare factors that teach the body to recognize and defend against infection by harmful pathogens, such as bacteria, viruses, and parasites. Vaccines provide a "taste" of a particular pathogen, which stimulates the body's immune system to prepare in case an infection occurs. Vaccines contain a harmless element of the infectious agent that stimulates the immune system to react, starting with the production of antibodies. Cells that respond to the vaccine proliferate both to produce antibodies specific to the causative agent and to form 'memory cells'. On a second encounter with the infectious agent, these memory cells are quickly able to deal with the threat by producing sufficient amounts of antibodies. Pathogens in the body are eventually destroyed, preventing further infection. Several infectious diseases such as smallpox, measles, mumps, rubella, diphtheria, tetanus, whooping cough, tuberculosis and polio are no longer a threat in Europe due to the successful implementation of vaccines.

For more information, see our report on "Protecting the world: Celebrating 200 years of vaccine research".

Veterinary Immunology

Veterinary immunology is a branch of immunology dedicated to improving the health of animals. Like humans, animals also suffer from diseases caused by organisms that try to invade their bodies or when their immune systems don't work properly. Wild, domestic and farmed animals are often exposed to a range of dangerous bacteria, viruses and parasites that threaten their well-being. Animal infections can have far-reaching effects on sectors of human work such as food and agriculture. In addition, many animal infections can be naturally transmitted across the species barrier to infect humans and vice versa, a process called zoonoses. For example, well-studied infections, including swine and bird flu, as well as malaria and Lyme disease, result from animal and insect transmission to humans. Therefore, it is very important to fight this kind of diseases effectively. These measures not only prevent further transmission to other animals and humans, but also mitigate any devastating social and economic impacts.

For more information, see our report on "Securing the future: the value of veterinary vaccines"