Species specific MDK expression analysis in wild-type mice and homozygous mice (H/H) by ELISA. Plasma was collected from wild-type mice (+/+) and homozygous B-hMDK mice (H/H), and then was analyzed by ELISA with mouse and human-specific MDK ELISA kit. Mouse MDK was detectable in wild-type mice and human MDK was detectable in homozygous mice.