Expression of wild-type and mutant fXI constructs. The 293 cells were transfected with 0.08 μg fXI/pJVCMV expression construct. (A) Relative concentrations of protein in media 67 hours after transfection compared with the mean for wild-type fXI, which was assigned a value of 100%. (B) Relative concentrations of intracellular fXI, again compared with wild-type fXI. Results are means and standard deviations for 9 separate transfections, each tested in triplicate by ELISA. Results are corrected for transfection efficiency using a Renilla luciferase assay. Lanes are as follows: (1) Wild-type fXI; (2) fXI-Glu117Stop; (3) fXI-Phe283Leu; (4) fXI-Gly350Glu; (5) fXI-Gly400Val; (6) fXI-Trp569Ser; and (7) pJVCMV without cDNA.