• SERPINB13 is a member of the serpin family of serine protease inhibitors, which can inhibit the activity of cathepsin K.
• The exons 2-8 of mouse Serpinb13 gene that encode the whole molecule (ATG to STOP codon) were replaced by human counterparts in B-hSERPINB13 mice. The promoter, 5’UTR and 3’UTR region of the mouse gene are retained. The human SERPINB13 expression is driven by endogenous mouse Serpinb13 promoter, while mouse Serpinb13 gene transcription and translation will be disrupted.
• SERPINB13 protein was detectable in lung, spleen, skin of wild-type C57BL/6 mice and homozygous B-hSERPINB13 mice.

Gene targeting strategy for B-hSERPINB13 mice. The exons 2-8 of mouse Serpinb13 gene that encode the whole molecule (ATG to STOP codon) were replaced by human counterparts in B-hSERPINB13 mice. The promoter, 5’UTR and 3’UTR region of the mouse gene are retained. The human SERPINB13 expression is driven by endogenous mouse Serpinb13 promoter, while mouse Serpinb13 gene transcription and translation will be disrupted.

Strain specific SERPINB13 expression analysis in homozygous B-hSERPINB13 mice by western blot. The pancreas, spleen, skin, stomach and lung tissues were collected from wild-type C57BL/6 mice (+/+) and homozygous B-hSERPINB13 mice (H/H), and analyzed by western blot with anti-SERPINB13 antibody (sigma, MABS1320). m/hSERPINB13 was detectable in lung, spleen, and skin of wild-type C57BL/6 mice (+/+) and homozygous B-hSERPINB13 mice.

Species specific analysis of SERPINB13 gene expression in wild-type C57BL/6N mice and homozygous humanized B-hSERPINB13 mice by RT-PCR. Skin was collected from wild-type C57BL/6N mice (+/+) and homozygous B-hSERPINB13 mice (H/H). Mouse Serpibn13 mRNA was detectable only in wild-type C57BL/6N mice. Human SERPINB13 mRNA was detectable only in homozygous B-hSERPINB13 mice, but not in wild-type C57BL/6N mice.