Targeted disruption of Glce and loss of IdoA containing HS. (A) A neo-cassette was inserted into the endogenous Glce gene by homologous recombination. Glce wild-type (top, WT or Glce+/+) and mutant allele (bottom, KO or Glce−/−). Mice were genotyped by PCR. F indicates forward primer; R1/R2, reverse primers; and P, probe (for primer sequences, see “Mice”). Representative PCR reactions are shown. (B) Left panel: Expression of IdoA containing HS on the cell surface of fetal liver cells of Glce+/+ and Glce−/− mice (E14.5) shown, respectively, as the light gray and black line (overlying the background stain), detected with antibody AO4B08. Right panel: Bar diagram represents the mean fluorescence intensity (MFI) ± SD of AO4B08 staining of Glce+/+ and Glce−/− fetal liver cells (n = 4). The dotted line indicates background staining. *P < .05.