The object of the present invention is to provide a cell that can exhibit physiological activity based on galectin-9, a method for producing the cell, and use of the cell. In order to achieve the above object, the cell of the present invention contains galectin-9, and the galectin-9 is expressed on a cell surface.

Provided herein are methods of producing natural killer cells using a two-step expansion and differentiation method. Also provided herein are methods of suppressing tumor cell proliferation, of treating individuals having cancer or a viral infection, comprising administering the NK cells produced by the method to an individual having the cancer or viral infection.

Safe, rapid, and efficient methods for producing antigen-specific T cells recognizing human papilloma virus (HPV antigens); HPV-specific T cells, and methods for treating HPV infections and HPV-related malignancies by adoptive transfer of HPV-specific T cells.

The invention relates to monoclonal antibody production and isolation, and particularly, although not exclusively, to a novel feeder cell line for culturing a monoclonal antibody-producing B cell. The invention also extends to the use of the feeder cell line in culturing a monoclonal antibody-producing B cell, and isolating the B cell from the cell culture media. The invention further extends to methods for culturing and isolating a monoclonal antibody-producing B cell, as well as a method for isolating a monoclonal antibody.