Strain specific NGAL expression analysis in homozygous B-hNGAL mice by ELISA. Serum was isolated from wild-type C57BL/6 mice (+/+) and homozygous B-hNGAL mice (H/H) and analyzed by ELISA with species-specific NGAL ELISA kit. Mouse NGAL was detectable in wild-type mice (A). Human NGAL was exclusively detectable in homozygous B-hNGAL mice but not in wild-type mice (B).