Nonhuman model animal unresponsive to immunopotentiating synthetic compound

A method for producing a Toll-like receptor (TLR)7 homozygous knockout mouse whose genome comprises a disruption of a TLR7 gene, wherein the TLR7 homozygous knockout mouse lacks an increase of interferon-α compared with a wild-type mouse when R-848 is intraperitoneally injected into the mouse, the method comprising the following steps:

• (i) constructing a targeting vector by replacing whole or a part of a gene fragment of a gene site including an intracellular region and a transmembrane region of a TLR7 gene obtained by screening a mouse gene library with a plasmid including a poly A signal and a marker gene;
• (ii) linearizing the targeting vector;
• (iii) introducing the linearized targeting vector into a mouse embryonic stem cell;
• (iv) microinjecting the targeted embryonic stem cell whose TLR7 gene function is deficient into a blastocyst of a mouse to generate a chimeric mouse;
• (v) intercrossing the chimeric mouse with a wild-type mouse to generate a heterozygote mouse, and (vi) intercrossing the heterozygote mouse.