Display constructs encoding EGF and PrP fusion proteins give rise to high surface expression on transiently transfected N2A cells. N2A cells were transfected with plasmids pD-EGF and pHIT60 (A to D) or pD-PrP111 and pHIT60 (E to H). Cells were stained with anti-PrP (α-PrP) antibody 6H4 (D and F), with anti-EGF antibody (B), or with anti-p30 antiserum (A and E), and bound antibody was detected with FITC-conjugated anti-mouse Ig (B, F, D, and H) or Cy3-conjugated anti-goat Ig (A and E). The merge of A and B is shown in panel C, and that of E and F is shown in panel G.