immune system

American  

noun

Anatomy.

1. a diffuse, complex network of interacting cells, cell products, and cell-forming tissues that protects the body from pathogens and other foreign substances, destroys infected and malignant cells, and removes cellular debris: the system includes the thymus, spleen, lymph nodes and lymph tissue, stem cells, white blood cells, antibodies, and lymphokines.

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immune system Scientific  

1. The body system in humans and other animals that protects the organism by distinguishing foreign tissue and neutralizing potentially pathogenic organisms or substances. The immune system includes organs such as the skin and mucous membranes, which provide an external barrier to infection, cells involved in the immune response, such as lymphocytes, and cell products such as lymphokines.

2. See also autoimmune disease immune response

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immune system Cultural  

1. The system in the body that works to ward off infection and disease. Central to this system are the white blood cells. Some white blood cells produce antibodies in response to specific antigens that may invade the body; others function as scavengers to fight infection by destroying bacteria and removing dead cells.

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Etymology

Origin of immune system

First recorded in 1960–65

Example Sentences

“You’re having radiation. Your immune system is still weak. And all those people there. All those germs. What if you get a cold and it turns into pneumonia and you wind up in the hospital?”

From Literature

People with weakened immune systems caused by health conditions that include HIV infection, diabetes, silicosis and severe kidney disease have a higher risk of getting TB.

From Los Angeles Times

Immunoglobulin is recommended for some people, such as infants under 12 months, pregnant people without immunity and those with weakened immune systems.

From Los Angeles Times

The immune system may respond with inflammation, which can worsen depressive symptoms.

From Science Daily

"Researchers still don't fully understand what happens in the immune system that causes lasting symptoms for some people and not others," says Imperial.

From BBC