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Types of Immune System
There are two main types of immune system- innate and adaptive. Innate immune system is the first line of defense against the infection and it is present at birth. It is composed of physical barriers such as skin and mucous membranes, and non-specific immune cells such as neutrophils and macrophages. These cells are present in the blood and tissues and they recognize and destroy any foreign invaders immediately.
Adaptive immune system is the second line of defense and it develops over time in response to specific infections. It is composed of white blood cells called lymphocytes, which are produced in the bone marrow. Lymphocytes recognize and destroy specific antigens (molecules that trigger an immune response) on the surface of the invading cells.
Types OF Immunity System
There are five types of immunity system in humans: innate, adaptive, mucosal, passive, and natural killer cells.
Innate immunity is the first line of defense and is present at birth. It is nonspecific, meaning that it attacks all invading organisms equally. Innate immunity includes physical barriers such as the skin and mucous membranes, as well as chemical substances such as tears and saliva that destroy invading organisms.
Adaptive immunity develops in response to a specific invader. It is specific to that invader, and therefore can mount a more effective attack. Adaptive immunity is mediated by lymphocytes, a type of white blood cell. There are two types of lymphocytes: T cells and B cells. T cells are responsible for destroying invading organisms, while B cells produce antibodies that coat invading organisms and make them easier to destroy.
Mucosal immunity is found in the lining of the nose, mouth, and gastrointestinal tract. It is specific to the organisms that come in contact with these surfaces, and is responsible for preventing them from entering the body.
Passive immunity is temporary and is acquired from another source, such as antibodies in breast milk or in a serum given to a person who has been exposed to a disease.
Natural killer cells are a type of lymphocyte that does not specifically target invading organisms, but instead destroys cancer cells and cells that have been infected with a virus.
Disorders of the Immune System
The immune system is a complex network of cells and organs that defends the body against infection. Disorders of the immune system can result in a wide range of symptoms, depending on the part of the immune system that is affected.
There are several types of disorders of the immune system. The most common are infections caused by viruses, bacteria, or other organisms. These infections can range from mild to life-threatening. Other disorders of the immune system include autoimmune diseases, in which the body’s own immune system attacks its own tissues, and allergy and asthma, which are caused by an overactive immune response.
Symptoms of immune system disorders vary depending on the type of disorder. Infections may cause fever, rash, and muscle aches. Allergy and asthma may cause sneezing, coughing, and wheezing. Autoimmune diseases may cause a wide range of symptoms, depending on the specific disease.
Most immune system disorders can be treated with medication or other therapies. Some, such as infections, can be cured. Others, such as autoimmune diseases, may be managed with medication and lifestyle changes.
It is important to see a doctor if you have any symptoms that suggest you may have an immune system disorder. Early diagnosis and treatment can help prevent serious health problems.
