Do the terms innate and adaptive immunity create conceptual barriers?

摘要

What is the difference between innate and adaptive immunity? Traditionally, innate immunity was assumed to be rapid, non-specific and identical qualitatively and quantitatively each time the same pathogen was encountered. Many innate immune cells are thought to be short-lived - for example, the lifespan of a neutrophil is estimated to be a few hours or days - making memory an irrelevant concept. Conversely, the hallmarks of adaptive immunity are thought to include the generation of long-lived, antigen-specific cells after initial exposure to an antigen or pathogen that can respond faster and more robustly on subsequent encounters with the same antigen or pathogen. Adaptive immunity is generally considered to be the exclusive domain of B and T cells; granulocytes, monocytes, macrophages, dendritic cells and natural killer (NK) cells have been delegated to the innate immune system, which also comprises epithelial cell barriers, complement, antimicrobial peptides and other soluble factors.