mRNA expression analysis

Strain specific analysis of PCSK9 gene expression in wild-type mice and B-hPCSK9 mice by RT-PCR. Mouse Pcsk9 mRNA was detectable in liver of wild-type mice (+/+). Human PCSK9 mRNA was detectable only in homozygous B-hPCSK9 but not in wild-type mice.

Protein expression analysis

Strain specific PCSK9 expression analysis in homozygous B-hPCSK9 mice by ELISA. Serum was collected from wild-type mice (+/+) and homozygous B-hPCSK9 mice (H/H), and analyzed by ELISA with species-specific PCSK9 ELISA kit. Mouse PCSK9 was detectable in wild-type mice. Human PCSK9 was exclusively detectable in homozygous B-hPCSK9 mice but not in wild-type mice.

Analysis of lipid metabolism after PCSK9 humanization in B-hPCSK9 mice

Anti-human PCSK9 antibody improved lipid metabolism in male B-hPCSK9 mice. Wild-type C57BL/6 and B-hPCSK9 mice were treated with Alirocumab (in house)/Evolocumab(in house) or isotype control antibody(single dose, s.c.) (n = 8). Blood were collected on Day -5, 1, 3, 5 and 8  for analysis. Serum levels of LDL-C (A) and TC(B) were reduced in the anti-human PCSK9 antibody treated male mice group compared to the isotype control. Results indicated that anti-human PCSK9 antibody were efficacious in controlling blood lipid in male B-hPCSK9 mice. Values are expressed as mean ± SEM. TC, total cholesterol; LDL-C, low density lipoprotein cholesterol. 

In vivo efficacy of anti-human PCSK9 antibody with WD-induced B-hPCSK9 mice

Anti-human PCSK9 antibody upregulated LDLR levels in male B-hPCSK9 mice. B-hPCSK9 mice were treated with Alirocumab (in house)/Evolocumab(in house) or isotype control antibody(single dose, s.c.) (n = 6). Liver tissues were collected on Day 8  for ELISA analysis. LDLR levels were upregulated in the anti-human PCSK9 antibody-treated male mice group compared to the isotype control. Values are expressed as mean ± SEM. LDLR, low-density lipoprotein cholesterol receptor.  WD, the Western diet.