Gene targeting strategy for B-hIL20 mice. The exons 1~5 of mouse Il20 gene that encodes the full-length protein were replaced by human IL20 exons 1~5 in B-hIL20 mice.

Strain specific IL20 expression analysis in homozygous B-hIL20 mice by ELISA. Serum was collected from wild-type C57BL/6 mice (+/+) and homozygous B-hIL20 mice (H/H), and analyzed by ELISA with IL20 ELISA kit. Mouse IL20 was detectable both in wild-type C57BL/6 mice and homozygous B-hIL20 mice. Human IL20 was also detectable both in wild-type mice and homozygous B-hIL20 mice. Both the ELISA kits are cross-recognized between human and mouse IL20.

Strain specific analysis of IL20 mRNA expression in wild-type C57BL/6 mice and B-hIL20 mice by RT-PCR. Genital fat pad RNA were isolated from wildtype C57BL/6 mice (+/+) and homozygous B-hIL20 mice (H/H), then cDNA libraries were synthesized by reverse transcription, followed by PCR with human IL20 primers. Human IL20 mRNA was detected in homozygous B-hIL20 mice but not in wild-type mice.