Figure 1: Generation of H2-Bl Expressing mESC and hESC Cell lines. (A) Schematic representation of the membrane bound (MB) and soluble (S) isoforms of H2-Bl used in these experiments. (B) Phase contrast image of the hESC line ENVY. (C) Phase contrast image of the mESC line R1. (D) The HA tag on of membrane bound H2-Bl molecule was detectable in both ES cell lines as shown by immunofluorescence. (E) Presence of both isoforms of the H2-Bl protein as detected by western blotting.