Gene targeting strategy for B-hDDR1 mice. The exons 3-12 of mouse Ddr1 gene that encode the extracellular sequences were replaced by human DDR1 exons 2-11 in B-hDDR1 mice.

Strain specific DDR1 expression analysis in homozygous B-hDDR1 mice by western blot. Brain collected from wild-type C57BL/6 mice (+/+) and homozygous B-hDDR1 mice (H/H), and analyzed by western blot with DDR1 antibodies. Human DDR1 was exclusively detectable in homozygous B-hDDR1 but not in wild-type mice. Mouse DDR1 was detectable in wild-type mice and homozygous B-hDDR1. The first DDR1 antibody is a human-specific antibody and the other is a human-mouse cross-recognition antibody.