innate immune system(redirected from Passive immune system)
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Related to Passive immune system: Innate immune system
innate immune system
The component of the immune system that is relatively nonspecific and immediate and includes mucous secretions, complement proteins, and certain white blood cells, especially neutrophils, macrophages, and dendritic cells. It is one of two main components of the vertebrate immune system, along with the adaptive immune system.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.