Human L- and P-selectin/μ chimera cross-react with CHO cells expressing mammalian homologues of PSGL-1. CHO cells, stably expressing similar levels of human C2GnT-I, FucT-VII and human (h), bovine (b), pig (p), rat (r) or equine (e) PSGL-1, were incubated with saturating concentrations of human P- or L-selectin/μ chimeras (filled histogram). Chimera binding was abrogated by 10 mM EDTA (open histogram). Human P- and L-selectin chimera did not bind (< 2%) to mock-transfected CHO cells (not shown). The percentage of positive cells and the mean fluorescence intensity are indicated in each histogram. Histograms are representative of 3–4 experiments.