• LRG-1 (Leucine-Rich alpha-2-Glycoprotein 1) is a 45-55 kDa, monomeric, variably glycosylated, secreted protein member of the leucine-rich repeat family of molecules, which is reported to bind multiple molecules, including TGF-beta, extracellular cytochrome C, and fibronectin plus collagen IV of the ECM.
• Mature human LRG-1 is 312 amino acids (aa) in length (aa 35-347), which shares 66% aa sequence identity with mouse LRG-1.
• The exons 1-2 of mouse Lrg1 gene that encode the whole molecule (ATG to STOP codon), including 3’UTR were replaced by human counterparts in B-hLRG1 mice. The promoter and 5’UTR region of the mouse gene are retained. The human LRG1 expression is driven by endogenous mouse Lrg1 promoter, while mouse Lrg1 gene transcription and translation will be disrupted.
• LRG1 was only detectable in serum of homozygous B-hLRG1 mice, but not in wild-type C57BL/6JNidfc mice.
• Mouse Lrg1 mRNA was only detectable in wild-type C57BL/6JNifdc mice. Human LRG1 mRNA was only detectable in homozygous B-hLRG1 mice.
• Application: This product is used for pharmacodynamics and safety evaluation of drugs.

Gene targeting strategy for B-hLRG1 mice. The exons 1-2 of mouse Lrg1 gene that encode the whole molecule (ATG to STOP codon), including 3’UTR were replaced by human counterparts in B-hLRG1 mice. The promoter and 5’UTR region of the mouse gene are retained. The human LRG1 expression is driven by endogenous mouse Lrg1 promoter, while mouse Lrg1 gene transcription and translation will be disrupted.

Species specific analysis of LRG1 gene expression in wild-type C57BL/6JNidfc mice and homozygous humanized B-hLRG1 mice by RT-PCR. Liver was collected from wild-type C57BL/6JNidfc mice (+/+) and homozygous B-hLRG1 mice (H/H). Mouse Lrg1 mRNA was detectable in wild-type C57BL/6JNidfc mice. Human LRG1 mRNA was detectable only in homozygous B-hLRG1 mice, but not in wild-type C57BL/6JNidfc mice.

Strain specific LRG1 expression analysis in wild-type C57BL/6JNidfc mice and homozygous humanized B-hLRG1 mice by ELISA. Serum was collected from wild-type C57BL/6JNidfc mice (+/+) (female, n=3, 7-week-old) and homozygous B-hLRG1 mice (H/H) (female, n=3, 7-week-old). Expression level of mouse and human LRG1 were analyzed by ELISA (anti-human LRG1 ELISA kit: Abcam, ab260066). Human LRG1 was exclusively detectable in homozygous B-hLRG1 mice (n=3). Values are expressed as mean ± SEM.