immune system
noun
: the bodily system that protects the body from foreign substances, cells, and tissues by producing the immune response and that includes especially the thymus, spleen, lymph nodes, special deposits of lymphoid tissue (as in the gastrointestinal tract and bone marrow), macrophages, lymphocytes including the B cells and T cells, and antibodies
Examples of immune system in a Sentence
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People who are taking long courses of certain antibiotics, use medical devices such as respirators and catheters, and those with weakened immune systems are at the highest risk of contracting a CRE infection, said the CDC.
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Mary Walrath-Holdridge, USA Today, 11 Oct. 2025
Those with the condition do not create enough insulin, the hormone that regulates blood sugar levels—because their immune system attacks the cells in the pancreas that produce it.
—Hannah Millington, MSNBC Newsweek, 10 Oct. 2025
While our study dating back to 1984 found that certain environmental contaminants induce T cells that suppress the immune system, further study on such cells was hampered by an inability in the field at large to isolate and characterize these cells.
—Mitzi Nagarkatti, The Conversation, 10 Oct. 2025
Groundbreaking discoveries about the immune system.
—Connor Greene, Time, 9 Oct. 2025
See All Example Sentences for immune system
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Mary Walrath-Holdridge, USA Today, 11 Oct. 2025
Those with the condition do not create enough insulin, the hormone that regulates blood sugar levels—because their immune system attacks the cells in the pancreas that produce it.
—Hannah Millington, MSNBC Newsweek, 10 Oct. 2025
While our study dating back to 1984 found that certain environmental contaminants induce T cells that suppress the immune system, further study on such cells was hampered by an inability in the field at large to isolate and characterize these cells.
—Mitzi Nagarkatti, The Conversation, 10 Oct. 2025
Groundbreaking discoveries about the immune system.
—Connor Greene, Time, 9 Oct. 2025
See All Example Sentences for immune system
Cite this Entry
“Immune system.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/immune%20system. Accessed 17 Oct. 2025.
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