AllergyOne malfunction of the immune system is an allergy. An allergy is an immune response against a non-harmful substance that normally not provoke such response. The substances that cause an allergic response are called allergens, for example, peanuts, latex, shellfish and pollen. A common allergy is a nasal allergy; about 50 million people in America have nasal allergies. Allergic rhinitis, a nasal allergy, impacts from 10% to 30% of the worldwide populaceWhen an allergen enters the blood- stream, it would be recognized by a specific B-cell as an antigen. The B-cell will then activate to produce plasma cell that makes IgE antibodies. People with allergies make more IgE compared to others. The body of the allergic person makes a specific IgE antibody that targets the allergen. The antibodies attach to the membrane of mast cells. Whenever the allergen enters the bloodstream, its antigens will bind to the antibodies. When the antigens attaches to two antibodies next to each other, the membrane becomes damaged so chemicals, such as histamine are released. The chemicals cause symptoms such as coughing, itchy eyes, runny noses, rashes and hives. The symptoms depend on what the allergen is. A common treatment for allergies is to avoid the allergen so it does not provoke a harmful response. In addition, one could take medicine to allay the symptoms. However, there is no cure for allergies, but it is possible to grow out an allergy as you get older.Autoimmune Disease Another malfunction of the immune system is an autoimmune disease. A body with an autoimmune disease assaults or harms itself. The body cannot distinguish from self and nonself in an autoimmune disease so the immune system induces an attack against a component on its own body. The body produces autoantibodies that attack healthy cells. In addition, regulatory T-cells overlook the mistake of the immune system. The cause of autoimmune diseases has not been found.More than 23 million Americans have an autoimmune disease. Autoimmune diseases affect 5% to 8% of the worldwide population. Some examples of autoimmune diseases are rheumatoid arthritis, lupus and multiple sclerosis. The symptoms vary depending on the autoimmune disease but some symptoms are pain, fatigue and fever. Medication can be used to suppress the immune responses. Therapy can assuage symptoms of autoimmune diseases.Immunodeficiency The last malfunction of the immune system is immune deficiency, or immuno -deficiency. In immunodeficiency disorders, the body is unable to fight against invaders. The immune cells are damaged/there is a small number of them. Primary and secondary are the two categories of immunodeficiency.  Primary immunodeficiency are present at birth. They can be caused by mutations or by inheritation. In primary immunodeficiency disorders, B-cell complications are common. Secondary immunodeficiency is acquired later in life. They can be caused by drugs and prolonged disorders. The body is infected more easily as a result of immunodeficiency disorders because the immune system cannot defend the body from such invaders. Some examples of immunodeficiency disorders are AIDS, SCIDS, XLA and CVID. Symptoms of immuno- deficiency disorders include sinus infections and pneumonia. Treatments for immunodeficiency disorders include treatment of the infections caused by the disorders, immunoglobulin therapy, antiviral drugs and antibiotic. The treatments depend on the disorder. There are 6 million people worldwide that have a primary immunodeficiency disorder. Around 1 in 1,200 people in the U.S. have a primary immuno- deficiency disorder. AIDS is the most common secondary disorder and is caused by HIV. Over a million people in the U.S. have HIV and over 36 million people worldwide have HIV/AIDS in 2016.