With this invention, production manner and the like of the cell population which the natural killer cell and/or the cell population which contains the cell which can differentiate in the natural killer cell, features that the process which it expands cultures under existing of the cell where the living thing response qualification medicine and the treatment which takes breeding talent are administered is included, contains the natural killer cell is offered.本発明によって、ナチュラルキラー細胞及び/又はナチュラルキラー細胞に分化し得る細胞を含有する細胞集団を、生物応答修飾剤及び増殖能を奪う処理が施された細胞の存在下で拡大培養する工程を包含することを特徴とする、ナチュラルキラー細胞を含有する細胞集団の製造方法などが提供される。
