humoral immunity(redirected from Humoral immune system)
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hu·mor·al im·mu·ni·ty(hyū'mŏr-ăl i-myū'ni-tē)
Antibodies produced by plasma B cells, found mainly in the blood, spleen, and lymph nodes, neutralize or destroy antigens in several ways. They kill organisms by activating the complement system; neutralize viruses and toxins released by bacteria; coat the antigen (opsonization) or form an antigen-antibody complex to stimulate phagocytosis; promote antigen clumping (agglutination); and prevent the antigen from adhering to host cells.