Fc fusion prolongs D′D3 but not FVIII survival in HA mice. VWF fragment levels (normalized to the value at 5 minutes as 100% [%5min], A) and FVIII levels (B) were followed in HA mice (n = 4-9) transfused with 200 μL pooled PPP derived from hydrodynamically injected Vwf^−/− mice (n = 5-6). Donor PPP composition (FVIII in %C57BL/6J, VWF in nM of subunit): wtVWF (122.6%, 15.5 nM), D′D3 (71.0%, 3.4 nM), and D′D3-Fc (90.0%, 3.2 nM). Data (mean ± SD) were nonlinearly regressed (curves) as a single-phase exponential decay. (B) FVIII levels are expressed as %C57BL/6J, where 100% is defined as the amount of FVIII in PPP pooled from 10 C57BL/6J mice. The FVIII levels in mice transfused with D′D3-Fc were not regressed because of insufficient time points; a line is drawn through the data points for visual assistance.