noun
natural killer cell; NK cell
A type of lymphocyte in the innate immune system that can kill virus-infected cells and tumor cells without prior sensitization.
ナチュラルキラー細胞は、がん細胞を攻撃する免疫細胞の一種です。
Natural killer cells are a type of immune cell that attacks cancer cells.
キラーT細胞 (cytotoxic T cell) requires prior activation and is part of the adaptive immune system, while ナチュラルキラー細胞 acts as part of the innate immune system without prior sensitization.
Loanword from English 'natural killer cell', composed of ナチュラルキラー (natural killer) + 細胞 (cell).