The mouse Ror1 gene was replaced by human ROR1 coding sequence in B-hROR1 MC38 cells. Human ROR1 is highly expressed on the surface of B-hROR1 MC38 cells.

Gene targeting strategy for B-hROR1 mice. The exons 2-7 of mouse Ror1 gene that encode the extracellular protein were replaced by human ROR1 exons 2-7 in B-hROR1 mice.

Strain specific analysis of ROR1 gene expression in wild-type C57BL/6 mice and B-hROR1 mice by RT-PCR. ROR1 mRNA was detectable in lung of wild-type C57BL/6 mice (+/+) and homozygous B-hROR1 mice (H/H) due to the high genetic similarity, and we sequenced and confirmed that the extracellular region of homozygous B-hROR1 mice (H/H) is the human ROR1 sequence.

Strain specific ROR1 expression analysis in homozygous B-hROR1 mice by western blot. Tissues were collected from WT mice (+/+) and homozygous B-hROR1 (H/H) mice, and analyzed by western blot with anti-ROR1 antibody. ROR1 was detectable in embryo of WT mice (+/+) and homozygous B-hROR1 mice (H/H) due to the cross-reactivity of antibodies.