Immunology is the study of your body’s defenses against disease-causing microorganisms and how these defences may break down. This discipline encompasses your immune system (thymus, spleen, lymph nodes and special deposits of lymphoid tissue in bone marrow) as well as lymphocytes such as B and T cells that make up this defense mechanism.
The Immune System
The immune system is an intricate network of organs, tissues and cells designed to protect our bodies against pathogenic germs and infections. Immunology is the scientific study of this system; immunotherapy — using components or antigens from your immune system as therapy — has become a central element of modern medical practice.
Immunology derives its name from two Greek words for immunity and life (immunos), meaning “protection against disease.” Immunology examines both levels of defense: innate and adaptive immunity.
Innate immunity is your body’s initial line of defense. It encapsulates all the body’s built-in mechanisms for recognizing and combatting invaders such as bacteria, viruses, and parasites. Leukocytes make up this first line of defense; neutrophils and basophils comprise this system and patrol both blood circulation and tissue tissue areas to detect signs of trouble; when detected they release substances to kill or at least debilitate microorganisms before signalling other immune system cells to come to rescue!
More tailored responses occur when the immune system detects foreign germs or substances not meant to exist within its borders, such as pollen or food allergies. When this happens, your body sends signals which cause white blood cells to produce antibodies against that substance – attaching themselves to it in order to mark it for destruction by other immune system cells.
Once an immune system recognizes a particular germ or substance, its memory of it is enhanced so it can react more quickly when another threat emerges. This is how vaccination works — using harmless, dead or weakened versions of disease-causing pathogens as “primers” so when real pathogens enter the body and provoke stronger secondary responses they can be more easily managed by the secondary response mechanisms in place.
Sometimes our immune systems become confused and mistakenly target healthy cells within the body – known as autoimmunity. Immunology studies this phenomenon, leading to diseases like Crohn’s disease, Hashimoto’s thyroiditis, rheumatoid arthritis, etc. Treatment of such conditions with immunotherapy remains key focus area.
Allergies
Immunology is the study of immunity, the complex network of cells and organs which protects our bodies against infection. Immunology also includes diseases caused by dysfunctions within this network such as allergies and autoimmunity; more recently it has also become evident that immune reactions play a part in many conditions that were once thought non-immune related such as metabolic disorders and cardiovascular disease.
The immune system has two primary lines of defense. Innate immunity provides general resistance against pathogens like bacteria, viruses, protozoa and fungi as well as parasitic organisms like helminth worms; its effectiveness does not improve with repeated exposure but simply serves as generalized defense against them. This type of defense does not build memory against specific organisms either.
Conversely, adaptive immunity provides more targeted responses against pathogens through antibody production against them. Once antibodies bind with pathogen surfaces they produce antibodies designed to recognize and destroy it before initiating a process called phagocytosis, in which macrophage cells of immune system engulf and destroy it.
Allergies arise when our immune systems mistakenly perceive something harmless as harmful and mount an attack against it, producing antibodies of the IgE class against allergens causing cells to release powerful chemicals like histamine which cause itchy, runny noses and watery eyes; an allergic response.
Some clinical immunologists work in hospitals treating patients with autoimmune diseases and allergies. They are trained to use various immunological laboratory tests to assess each individual patient, diagnose, treat, and ultimately prevent further complications. Furthermore, clinical immunologists are skilled at administering immunotherapy treatment by gradually exposing them to allergens over time to build immunity gradually – this method is beneficial in the treatment of conditions like rheumatoid arthritis, Hashimoto’s thyroiditis, as well as some cancers.
Autoimmune Diseases
Immunology encompasses not only the study of natural defence mechanisms in the body, but also an increasing focus on understanding how our immune systems can malfunction. When this happens, autoimmune diseases arise whereby parts of the immune system mistakenly attack parts of the body it mistakes for invaders, leading to serious complications like type 1 diabetes, multiple sclerosis and rheumatoid arthritis – among many others.
As part of an effective immune response, lymphocytes (cells that produce antibodies) detect disease-causing microorganisms through lymph node lymphocytes which recognize antigens; upon recognition they produce proteins called antibodies which target and neutralise pathogens which are then cleared away by phagocytes (cells that engulf and destroy invading pathogens).
Researchers theorize that some lymphocytes possess the ability to recognize “self” molecules. Under normal circumstances, when this happens, the immune system usually responds by suppressing that cell’s proliferation; but in autoimmune diseases this does not happen and lymphocytes instead attack tissues of patients causing severe symptoms, including type 1 diabetes, rheumatoid arthritis and lupus.
Immunology has made significant advances in our battle against disease. Edward Jenner’s revolutionary experiments during the 18th Century resulted in vaccination, which is probably responsible for saving more lives than any other medical breakthrough. Immunology also allows scientists to transplant organs between people without fear of rejection by their immune systems. Furthermore, immunologists are developing medications which enhance or suppress specific immune systems for greater effectiveness against specific conditions.
Untiringly, recent evidence points towards the immune system being involved in many disorders not traditionally considered immunological – including metabolic and cardiovascular conditions as well as neurodegenerative diseases like Alzheimer’s. Understanding how our immune systems operate is vital to maintaining our health and combatting infectious diseases – Immunology being one of the fastest expanding fields in both science and medicine.
Immunotherapy
Immunology has made major strides forward in treating cancer and other diseases. Our immune system serves as our natural defence against infection, but overreactive immunity may cause allergies or autoimmune disorders. Clinical immunology applies our understanding of how immune systems operate to treating disease through vaccinations, cytokine inhibitors, G-CSF (granulocyte colony-stimulating factor) or interferons.
Once the innate system has been overwhelmed by an infection, adaptive immunity (or acquired immunity) kicks into effect to provide specific and enhanced responses against future challenges. Key components of adaptive immunity include lymphocytes such as B and T cells that recognize antigens and produce antibodies to bind with and neutralise them.
Immunology has played a pivotal role in medical innovation, including vaccines and monoclonal antibodies. Furthermore, immunology research has had an impactful influence on other areas of health care; immunosuppressive techniques are commonly used to protect transplanted organs and bone marrow from rejection by immune systems. Furthermore, this field has led us closer towards understanding how our immune systems operate to maintain homeostasis and the homeostatic balance they strive for.
Now it is recognized that immune responses play a key role in various common conditions, including allergy and autoimmune diseases. This has lead to new immunotherapies which use this system as a weapon against cancer and other illnesses.
Cancer immunotherapy is an exciting area of research, with several effective therapies already in use – checkpoint blockade, vaccines, oncolytic viruses and monoclonal antibodies being among them. Our experts at Penn Medicine offer patients assistance in taking full advantage of their treatment; helping them understand side effects and how best to manage them as well as providing support throughout the journey from diagnosis through recovery. It is vitally important that any time side effects arise they report them immediately so that the appropriate healthcare team can monitor your condition quickly.