Gene targeting strategy for B-hDLL3 mice. The exons 2-7 of mouse Dll3 gene that encode the extracellular domain were replaced by human DLL3 exons 2-7 in B-hDLL3 mice.

Strain specific analysis of DLL3 gene expression in wild type (WT) mice and B-hDLL3 mice by RT-PCR. Mouse Dll3 mRNA was detectable in testis of WT mice (+/+). Human DLL3 mRNA was detectable in homozygous B-hDLL3 mice (H/H) but not in WT mice (+/+).

Western blot analysis of DLL3 protein expression in homozygous B-hDLL3 mice. Various tissue lysates were collected from wild-type C57BL/6 mice (+/+) and homozygous B-hDLL3 mice (H/H), and then analyzed by western blot with anti-DLL3 antibody (CST, 2483s). 40 μg total proteins were loaded for western blotting analysis. DLL3 was detected in brain, lung, testis, kidney, liver and heart of both B-hDLL3 mice and wild-type C57BL/6 mice due to the cross-reactivity of the antibody.