Method of producing an antibody

A method of producing a human antibody comprising:

• introducing human B-cells, or both human B cells and T-cells, or human stem cells which differentiate into human B-cells or both human B cells and T-cells, into a mouse produced by a method comprising backcrossing a mouse B with a mouse A, wherein said mouse A is a mouse obtained by backcrossing a Severe Combined Immunodeficiency (SCID) mouse with a non-obese diabetic (NOD) mouse;
• and wherein said mouse B is an interleukin 2-receptor γ chain gene knockout mouse, wherein said mouse produced by the method retains the human B-cells or both human B cells and T-cells;
• immunizing said mouse with an antigen;
• and
• collecting the human antibody produced from the mouse.

A method of producing an antibody-producing cell line which produces a human antibody, comprising:

• introducing human B-cells, or both human B cells and T-cells, or human stem cells which differentiate into human B-cells or both human B cells and T-cells, into a mouse produced by a method comprising backcrossing a mouse B with a mouse A, wherein said mouse A is a mouse obtained by backcrossing a Severe Combined Immunodeficiency (SCID) mouse with a non-obese diabetic (NOD) mouse;
• and wherein said mouse B is an interleukin 2-receptor γ chain gene knockout mouse, wherein said mouse produced by the method retains the human B-cells or both human B cells and T-cells;
• immunizing said mouse with an antigen;
• collecting from the mouse a cell which produced the antibody against the antigen;
• and
• establishing a cell line of the cell.