Immune Systemenparentshttps://kidshealth.org/EN/images/headers/P-immuneBB-enHD-AR1.gifThe immune system, composed of special cells, proteins, tissues, and organs that protect against germs and microorganisms, is the body's defense against disease.immunity, imunity, imune, am i immune? imune to, immune response, lymph, lymf, limph, lymphatic, limphatic, limfatic, gland, swollen glands, antibody, antibodies, autoimmune, innate immunity, adaptive immunity, passive immunity, asthma, allergies, immunodeficiency, lymphoma, limfoma, leukemia, lukemea, lukiemea, lupus, JRA, arthritis, HIV/AIDS, antigen, lukocytes, leukocytes, lymphoid, phagocyte, fagosite, lymphocyte, limfocite, CD1Allergy07/06/200006/09/202006/09/2020Larissa Hirsch, MD10/01/2019d5495b69-ecfe-4b16-a87f-a9f5664e71d6https://kidshealth.org/ws/RadyChildrens/en/parents/immune.html/<h3>What Is the Immune System?</h3> <p>The immune system is the body's defense against infections. The immune (ih-MYOON) system attacks <a href="https://kidshealth.org/ws/RadyChildrens/en/parents/germs.html/">germs</a> and helps keep us healthy.</p> <h3>What Are the Parts of the Immune System?</h3> <p>Many cells and organs work together to protect the body. White blood cells, also called <strong>leukocytes</strong>&nbsp;(LOO-kuh-sytes), play an important role in the immune system.</p> <p>Some types of white blood cells, called <strong>phagocytes</strong> (FAH-guh-sytes), chew up invading organisms. Others, called <strong>lymphocytes</strong> (LIM-fuh-sytes), help the body remember the invaders and destroy them.</p> <p>One type of phagocyte is the <strong>neutrophil</strong>&nbsp;(NOO-truh-fil), which fights bacteria. When someone might have bacterial infection, doctors can order a blood test to see if it caused the body to have lots of neutrophils. Other types of phagocytes do their own jobs to make sure that the body responds to invaders.</p> <p>The two kinds of lymphocytes are <strong>B lymphocytes</strong> and <strong>T lymphocytes</strong>. Lymphocytes start out in the bone marrow and either stay there and mature into B cells, or go to the thymus gland to mature into T cells. B lymphocytes are like the body's military intelligence system &mdash; they find their targets and send defenses to lock onto them. T cells are like the soldiers &mdash; they destroy the invaders that the intelligence system finds.</p> <h3>How Does the Immune System Work?</h3> <p>When the body senses foreign substances (called antigens), the immune system works to recognize the antigens and get rid of them.</p> <p>B lymphocytes are triggered to make <strong>antibodies</strong> (also called <strong>immunoglobulins</strong>). These proteins lock onto specific antigens. After they're made, antibodies usually stay in our bodies in case we have to fight the same germ again. That's why someone who gets sick with a disease, like chickenpox, usually won't get sick from it again.</p> <div class="rs_skip rs_preserve"><!-- TinyMCE Fix --> <script src="//familysurvey.org/misc/javascript/js_apps/video/kh-video-metadata.js" type="text/javascript"></script> <script src="//familysurvey.org/misc/javascript/js_apps/video/kh-video-controller.js" type="text/javascript"></script> <script src="//familysurvey.org/misc/javascript/js_apps/video/single-covid-antibodies-en.js" type="text/javascript"></script> </div> <p>This is also how immunizations (vaccines) prevent some diseases. An immunization introduces the body to an antigen in a way that doesn't make someone sick. But it does let the body make antibodies that will protect the person from future attack by the germ.</p> <p>Although antibodies can recognize an antigen and lock onto it, they can't destroy it without help. That's the job of the <strong>T cells</strong>. They destroy antigens tagged by antibodies or cells that are infected or somehow changed. (Some T cells are actually called "killer cells.") T cells also help signal other cells (like phagocytes) to do their jobs.</p> <p>Antibodies also can:</p> <ul> <li>neutralize toxins (poisonous or damaging substances) produced by different organisms</li> <li>activate a group of proteins called <strong>complement</strong> that are part of the immune system. Complement helps kill bacteria, viruses, or infected cells.</li> </ul> <p>These specialized cells and parts of the immune system offer the body protection against disease. This protection is called immunity.</p> <p>Humans have three types of immunity &mdash; innate, adaptive, and passive:</p> <ul class="kh_longline_list"> <li><strong>Innate immunity:</strong> Everyone is born with innate (or natural) immunity, a type of general protection. For example, the skin acts as a barrier to block germs from entering the body. And the immune system recognizes when certain invaders are foreign and could be dangerous.</li> <li><strong>Adaptive immunity:</strong> Adaptive (or active) immunity develops throughout our lives. We develop adaptive immunity when we're exposed to diseases or when we're immunized against them with vaccines.</li> <li><strong>Passive immunity:</strong> Passive immunity is "borrowed" from another source and it lasts for a short time. For example, antibodies in a mother's breast milk give a baby temporary immunity to diseases the mother has been exposed to.</li> </ul> <p>The immune system takes a while to develop and needs help from <a href="https://kidshealth.org/ws/RadyChildrens/en/parents/vaccine.html/">vaccines</a>. By getting all your child's <a href="https://kidshealth.org/ws/RadyChildrens/en/parents/immunization-chart.html/">recommended vaccines</a> on time, you can help keep your child as healthy as possible.</p>Sistema inmunitarioEl sistema inmunitario es el sistema de defensa del cuerpo contra las infecciones. El sistema inmunitario ataca a gérmenes invasores y nos ayuda a mantenernos sanos.https://kidshealth.org/ws/RadyChildrens/es/parents/immune-esp.html/7211323f-49f0-4eab-accb-a8ad0f694f74
Activity: Immune SystemDo you know your immune system? Label the parts of the system that keeps you well.https://kidshealth.org/ws/RadyChildrens/en/kids/bfs-isactivity.html/b7b591d8-8c4c-45da-bac6-7024077d78c2
ArthritisKids can get a kind of arthritis that causes joint pain. Find out more in this article for kids.https://kidshealth.org/ws/RadyChildrens/en/kids/juv-rheum-arthritis.html/8d74d9e3-5b65-49cb-86b1-f03a78d98bb9
Blood Test: Immunoglobulin A (IgA)Checking IgA levels can help doctors diagnose problems with the immune system, intestines, and kidneys. It's also used to evaluate autoimmune conditions, such as rheumatoid arthritis, lupus, and celiac disease.https://kidshealth.org/ws/RadyChildrens/en/parents/test-iga.html/e6ff7325-c068-4bcf-85ed-f333a801ed5f
Blood Test: Thyroid Peroxidase AntibodiesThe thyroid peroxidase antibodies test is primarily used to help diagnose and monitor autoimmune conditions involving the thyroid gland, including Hashimoto's thyroiditis and Graves disease.https://kidshealth.org/ws/RadyChildrens/en/parents/test-peroxidase.html/04fa9666-9d47-4c66-9a18-bdc2dfbbf07f
Definition: AutoimmunitySometimes the immune system makes a mistake and attacks the body's own tissues or organs. This is called autoimmunity.https://kidshealth.org/ws/RadyChildrens/en/parents/autoimmunity.html/edc80a38-19f2-45c0-b3bb-a5706331f12b
Food AllergiesStruggling with strawberries? Petrified of peanuts? Sorry you ate shellfish? Maybe you have a food allergy. Find out more in this article for kids.https://kidshealth.org/ws/RadyChildrens/en/kids/food-allergies.html/e56e2bf2-b47d-46d4-886a-4c90accbb7a7
HIV and AIDSParents can help prevent HIV/AIDS by learning the facts and talking with their kids regularly about healthy behaviors, feelings, and sexuality.https://kidshealth.org/ws/RadyChildrens/en/parents/hiv.html/31cac64c-2167-4e8f-bbff-830521bb29c6
Immune SystemThe immune system is made up of special cells, proteins, tissues, and organs that defend people against germs and microorganisms.https://kidshealth.org/ws/RadyChildrens/en/teens/immune.html/45385c22-09f4-4e2e-98d9-8be5155bedc5
Immunotherapy to Treat CancerThis promising new type of cancer treatment stimulates a person's immune system so it is better able to fight disease.https://kidshealth.org/ws/RadyChildrens/en/parents/immunotherapy.html/1cab6bec-f6ce-4ea5-a4d3-f2fbfc0e4559
Juvenile Idiopathic ArthritisIn juvenile idiopathic arthritis (also called juvenile rheumatoid arthritis)), a person can develop swollen, warm, and painful joints. Learn more.https://kidshealth.org/ws/RadyChildrens/en/parents/jra.html/64ceaa10-23cf-4f1c-b6e0-21bd7cb07b97
Juvenile Idiopathic Arthritis (JIA)Learn about juvenile idiopathic arthritis, a specific kind of arthritis that usually occurs in kids and teens younger than 17.https://kidshealth.org/ws/RadyChildrens/en/teens/juv-rheumatoid-arthritis.html/f118a90b-88e2-491c-bad2-24a8ef6e2144
LupusLupus is known as an autoimmune disease in which a person's immune system mistakenly works against the body's own tissues.https://kidshealth.org/ws/RadyChildrens/en/parents/lupus.html/5d0f4916-af65-49d3-afff-09d656af8ff1
Movie: Immune SystemWatch this movie about your immune system - the system that keeps you healthy.https://kidshealth.org/ws/RadyChildrens/en/kids/ismovie.html/2fa4168d-112b-489c-aafa-d2e199ae1ab9
NeutropeniaCertain cancers, or cancer treatment, can weaken the immune system, requiring a child to stay home to avoid exposure to germs. Here are ways to help your child make the best of it.https://kidshealth.org/ws/RadyChildrens/en/parents/neutropenia.html/e6c76bd6-23c1-4e34-98ac-1d737131d51f
Severe Combined ImmunodeficiencySevere combined immunodeficiency (SCID) is an immune deficiency that can be successfully treated if it's found early.https://kidshealth.org/ws/RadyChildrens/en/parents/severe-immunodeficiency.html/abe0da22-f4d2-453c-9acb-39b9ed61f021
The Danger of Antibiotic OveruseTaking antibiotics too often or for the wrong reason has led to a dangerous rise in bacteria that no longer respond to medicine. Find out what you can do to prevent antibiotic overuse.https://kidshealth.org/ws/RadyChildrens/en/parents/antibiotic-overuse.html/35450851-5c65-4c1e-bab3-b8668a7b309d
What Are Glands?You've heard of glands, but what are they? Find out in this article for kids.https://kidshealth.org/ws/RadyChildrens/en/kids/glands.html/18e35f17-fa0b-4977-b705-dff0c7e529c7
Word! AutoimmunityYour immune system fights infections and illnesses. But sometimes the immune system makes a mistake and attacks part of the body. This is called autoimmunity.https://kidshealth.org/ws/RadyChildrens/en/kids/word-autoimmunity.html/dd6af6b4-4a4d-443d-b446-85399d19e2ba
Your Immune SystemThe immune system keeps you healthy. How does it work? Find out in this article for kids.https://kidshealth.org/ws/RadyChildrens/en/kids/immune.html/6b9fad76-c866-450e-81d9-1e625343744f
kh:age-allAgesOrAgeAgnostickh:clinicalDesignation-immunologykh:genre-articlekh:primaryClinicalDesignation-immunologyBody Basicshttps://kidshealth.org/ws/RadyChildrens/en/parents/general/body-basics/3113dcac-be5e-44dd-842b-232a50bfd496Body Basics: Cerebral Palsyhttps://kidshealth.org/ws/RadyChildrens/en/parents/cerebralpalsy-center/cp-bb/2d58aab5-7b9d-45d2-bb45-49f5c3613e1bBody Basics: Cancerhttps://kidshealth.org/ws/RadyChildrens/en/parents/cancer-center/body-basics/d4ed9bbd-3f41-4885-a3e2-6d755d332de2Body Basics: Sports Medicinehttps://kidshealth.org/ws/RadyChildrens/en/parents/sports-medicine-center/body-basics/bf343536-f9b0-49b1-8690-95fd2bff9a42