Strain specific IGFBP7 expression analysis in homozygous B-hIGFBP7 mice by ELISA. Serum was collected from wild-type mice (+/+) and homozygous B-hIGFBP7 mice (H/H), and analyzed by ELISA with species-specific IGFBP7 ELISA kit. Mouse IGFBP7 was detectable in wild-type mice. Human IGFBP7 was exclusively detectable in homozygous B-hIGFBP7 mice but not in wild-type mice.