Gene targeting strategy for B-hICOSL mice. The exons 3-5 of mouse Icosl gene that encode the extracellular domain were replaced by human ICOSL exons 3-5 in B-hICOSL mice.

Strain specific ICOSL expression analysis in heterozygous B-hICOSL mice by flow cytometry. Splenocytes were collected from wild type (WT) mice (+/+) and heterozygous B-hICOSL mice (H/+), and analyzed by flow cytometry with anti-mouse ICOSL antibody and prezalumab analog (in house). Mouse ICOSL was detectable in WT mice (+/+) and heterozygous B-hICOSL mice (H/+). Human ICOSL was exclusively detectable in heterozygous B-hICOSL mice (H/+) but not in WT mice (+/+).

Strain specific ICOSL expression analysis in heterozygous B-hICOSL mice by flow cytometry. Splenocytes were collected from wild type (WT) mice (+/+) and heterozygous B-hICOSL mice (H/+), and analyzed by flow cytometry with anti-human ICOSL antibody A and antibody B provided by the client. Mouse ICOSL was detectable in WT mice (+/+) and heterozygous B-hICOSL mice (H/+). Human ICOSL was exclusively detectable in heterozygous B-hICOSL mice (H/+) but not in WT mice (+/+).