Immunology: What is it? Importance, Immune System, Complications and Vaccines

It is an essential branch of the medical and biological sciences because it studies the immune system.

The immune system protects us from infections through several lines of defense. If it is not working as it should, it can cause diseases such as autoimmunity, allergies, and cancer.

New research supports that immune responses contribute to developing many common disorders that were not previously considered immunological, including metabolic, cardiovascular, and neurodegenerative diseases, such as Alzheimer’s.

Importance of immunology

Immunology has changed the face of modern medicine. Immunological research extends horizons in our understanding of how to treat significant health problems, autoimmune diseases, and vaccines for emerging pathogens like Ebola.

It has also facilitated the discovery of new diagnoses and treatments to manage various diseases.

In addition to the advancement of technology, immunological research has provided critical research techniques and tools, such as flow cytometry and antibody technology.

What is the immune system?

It is a complex system of structures and processes that have evolved to protect us from diseases. The molecular and cellular components make up the immune system.


The function of these components is divided into non-specific mechanisms, innate to an organism, and receptive responses, which are adaptive to specific pathogens.

Fundamental or classical immunology involves studying the components that make up the innate and adaptive immune system.

The first line of defense is innate immunity. The answers are the same for all potential pathogens, regardless of their differences.

Innate immunity includes physical barriers (e.g., skin, saliva, etc.) and cells (e.g., macrophages, neutrophils, basophils, mast cells, etc.).

These components protect an organism during the first days of infection. In some cases, this is enough to clean the pathogen, but in other cases, the first defense is overwhelmed, and the second line of defense is activated.

Adaptive immunity is the second line of defense that involves accumulating the memory of the infections found to mount an improved response specific to the pathogen or foreign substance.

This immunity involves antibodies, which usually target foreign pathogens that roam freely in the bloodstream.

T cells are also involved, mainly targeted towards pathogens that have colonized cells and can directly kill the infected cells or help control the antibody response.

Immunological dysfunction and clinical immunology

The immune system is highly regulated and balanced, and the disease can result when the balance is disturbed.

Research in this area involves studying the disease caused by the dysfunction of the immune system.

Much of this work is essential in developing new therapies and treatments that can manage or cure the disease by altering how the immune system works or preparing it to attack specific pathogens in the case of vaccines.

Immunodeficiency disorders involve problems with the immune system that impair your ability to mount an adequate defense.

As a result, these are almost always associated with severe infections that persist, reappear and lead to complications, making these disorders severely debilitating and even fatal.

There are two types of immunodeficiency disorders:

  • The primaries: are usually present from birth, are generally hereditary, and are relatively rare. Such an example is common variable immunodeficiency (CVID).
  • Secondary: usually develops later in life and may result from an infection, as is the case of AIDS after HIV infection.

Autoimmune diseases occur when the immune system attacks the body it must protect.

People with autoimmune diseases have a defect that prevents them from distinguishing their “own” molecules from the “non-owned” or “strange” molecules.

The immunology principles have provided various laboratory tests to detect autoimmune diseases.

Are allergies autoimmune diseases?

Allergies are hypersensitivity disorders when the body’s immune system reacts against harmless foreign substances, damaging the body’s tissues.

Almost any substance can cause allergies, but the most common is that allergies arise after eating certain types of food, such as peanuts, or inhaling substances suspended in the air, such as pollen or dust.

The body believes allergens are dangerous in allergic reactions and immediately produces substances to attack them.

This causes the immune system cells to release potent chemicals such as histamine, which causes inflammation and many symptoms associated with allergies.

Immunology strives to understand what happens to the body during an allergic response and the factors responsible for causing them. This should lead to better methods of diagnosis, prevention, and control of allergic diseases.

Does asthma belong to autoimmune diseases?

Asthma is a debilitating and sometimes fatal disease of the airways. It generally occurs when the immune system responds to inhaled particles in the air and can thicken the airways in patients over time.

It is a significant cause of disease and is particularly common in children. In some cases, it has an allergic component; however, the origin is more complex and little known in many instances.

How does the immune system attack cancer cells?

Cancer is a disease of abnormal and uncontrollable cell growth and proliferation and is defined by a set of characteristics, one of which is the ability of cancer cells to prevent immune destruction.

With the knowledge that evasion of the immune system can contribute to cancer, researchers have resorted to its manipulation to overcome cancer (immunotherapy).

Immunotherapy against cancer seeks to stimulate the innate powers of the immune system to fight cancerous tissue and has shown extraordinary promise as a new weapon in our arsenal against this disease.

Other applications of immunological knowledge against cancer include the use of monoclonal antibodies.

An example is Herceptin, a monoclonal antibody used to treat breast and stomach cancer.

What are the complications that the immune system generates in organ transplants?

Transplants involve the transfer of cells, tissues, or organs from a donor to a recipient.

The most formidable barrier to transplants recognizes the immune system of transplanted organs as strangers.

Understanding rejection mechanisms and clinical characteristics are vital in determining a diagnosis.

Because rejection risks are not diminished, the immune system will attack the transplanted organ, which will mean future complications that can generate a new operation or even the patient’s death.

The drugs developed for the organism to accept the transplanted organs are fundamental in this delicate and invasive operation to avoid fatalistic results.

What effect do vaccines have on the immune system?

Vaccines are agents that teach the body to recognize and defend against infections caused by harmful pathogens, such as bacteria, viruses, and parasites.

The vaccines provide an advance of a specific pathogen, which stimulates the body’s immune system to prepare itself in the event of an infection.

The vaccines contain a harmless element of the infectious agent that stimulates the immune system to mount a response, beginning with the production of antibodies.

The cells that respond to the vaccine proliferate to make specific antibodies and the provoking agent and form “memory cells.”

By finding the infectious agent a second time, these memory cells can deal quickly with the threat by producing sufficient amounts of antibodies. The pathogens inside the body are finally destroyed, which frustrates the 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 application of vaccines.