A method for preparing a cell population comprising cells each being CCR5-positive, CCR6-positive, CXCR3-positive, and CD3-negative, which comprises the following steps:
- (a) preparing a primary mononuclear cell population,
- (b) removing CD3-positive cells from the primary mononuclear cell population,
- (c) removing any selected from the group consisting of monocytes and B cells from the primary mononuclear cell population, and
- (d) culturing the cell population remained after removing CD3-positive cells, and any selected from the group consisting of monocytes and B cells in a medium containing IL-2.