Strain specific CXCL1 expression analysis in homozygous B-hCXCL1 mice by ELISA. Serum were collected from wild-type mice (+/+) and homozygous B-hCXCL1 mice (H/H) stimulated with 20ug/200ul LPS in vivo. Then, analyzed by ELISA with species-specific CXCL1 ELISA kit. Mouse CXCL1 was detectable in wild-type mice. Human CXCL1 was exclusively detectable in homozygous B-hCXCL1 mice but not in wild-type mice.