Gene targeting strategy for B-hFGL2 mice. The exons 1-2 of mouse Fgl2 gene that encode the full-length protein were replaced by human FGL2 exons 1-2 in B-hFGL2 mice.

Strain specific analysis of FGL2 gene expression in wild-type mice and B-hFGL2 mice by RT-PCR. Mouse Fgl2 mRNA was detectable in peritoneal exudative macrophages of wild-type mice (+/+). Human FGL2 mRNA was detectable only in homozygous B-hFGL2 mice (H/H) but not in wild-type mice. Strain specific FGL2 expression analysis in homozygous B-hFGL2 mice by western blot. Peritoneal exudative macrophages and splenocytes were collected from wild-type C57BL/6 mice (+/+) and homozygous B-hFGL2 mice (H/H), respectively and stimulated by mIFNγ (20 ng/ml) in vitro for 24h. These samples were then analyzed using Western blotting with an anti-FGL2 antibody. FGL2 was detectable in both wild-type and homozygous B-hFGL2 mice, as the antibody is cross-reactive with FGL2 in both humans and mice.