Cd28^tm1Pjl

The gene was disrupted by replacement of a 0.5 kb region containing most of exon 2 with a neomycin resistance cassette. Exon 2 encodes the Ig-like region, an alternative splice site, a putative ligand-binding domain, and represents more than 70% of the extracellular domain. Absence of gene expression was verified by flow cytometry of CD4+ T cells from homozygous mutant animals. (J:25536)