FXII is a protease that is primarily produced in the liver and circulates as a single-chain zymogen in plasma, playing an important role in the intrinsic pathway of blood coagulation and hemostasis. Upon contact with negatively charged surfaces, FXII converts into its double-stranded active form, FXIIa. The absence of FXII in humans and mice does not affect normal hemostasis ability, and the lack of FXII can inhibit thrombus formation, making it an important target in thrombosis treatment.

Gene editing strategy: The exons 1~14 of mouse FXII gene that encode full-length protein were replaced by the exons 1~14 of human FXII gene in B-hFXII mice.

mRNA expression analysis: Mouse FXII mRNA was detectable in liver of wild-type (+/+) and heterozygous B-hFXII mice (H/+) . Human FXII mRNA was detectable in heterozygous B-hFXII mice (H/+) but not in wild-type mice.

Protein expression analysis: Mouse FXII was only detectable in wild-type mice, Human FXII was detectable in homozygous B-hFXII mice (H/H) but not in wild-type mice (+/+).

Application: This product is used for pharmacodynamics and safety evaluation of cardiovascular diseases such as thrombosis.

Gene targeting strategy for B-hFXII mice. The exons 1~14 of mouse FXII gene that encode full-length protein were replaced by the exons 1~14 of human FXII gene in B-hFXII mice.