All of the following are pa of the innate immunity except -

Natural killer cells (NK cells) are a component of the innate immune system that does not directly attack invading microbes. Other components are mast cells, eosinophils, basophils; and the phagocytic cells including macrophages, neutrophils,complement cascade and dendritic cells. Ref: Ananthanarayan & Panikers textbook of microbiology 9th edition pg.no. : 78-81