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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What followed was not just recovery from cancer, but the rebuilding of an immune system erased by the very treatment that saved her life, Sullivan tells PEOPLE.
—
Tereza Shkurtaj, PEOPLE, 23 May 2026
Outside experts said the medications may affect cancer growth through several pathways, including reducing inflammation, altering tumor metabolism and improving immune system activity.
—Anthony Thompson, USA Today, 23 May 2026
Those at higher risk for severe pneumonia and sepsis include older adults and smokers, as well as those with chronic lung disease, diabetes, weakened immune systems or recent viral infections.
—Melissa Rudy, FOXNews.com, 23 May 2026
Typically the immune system releases chemicals to fight off pathogens such as bacteria, viruses or fungi, but with sepsis the response goes into overdrive.
—Steve Reed, Los Angeles Times, 23 May 2026
See All Example Sentences for immune system
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Tereza Shkurtaj, PEOPLE, 23 May 2026
Outside experts said the medications may affect cancer growth through several pathways, including reducing inflammation, altering tumor metabolism and improving immune system activity.
—Anthony Thompson, USA Today, 23 May 2026
Those at higher risk for severe pneumonia and sepsis include older adults and smokers, as well as those with chronic lung disease, diabetes, weakened immune systems or recent viral infections.
—Melissa Rudy, FOXNews.com, 23 May 2026
Typically the immune system releases chemicals to fight off pathogens such as bacteria, viruses or fungi, but with sepsis the response goes into overdrive.
—Steve Reed, Los Angeles Times, 23 May 2026
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 24 May. 2026.
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