Serum-derived FALP bears less fibrinogen than plasma-derived FALP but an equal amount of FHRP.

FALP was prepared from serum or plasma from the same donor. Samples derived from an equal amount of serum or plasma (∼30 mL) were diluted equivalently. Western blot analyses were performed with the starting serum or plasma, the flow-through of the first column chromatographic step (sFT and pFT), and the final FALP preparations (sFALP and pFALP). Anti-FHRP was used for the blot shown in panel A, and antifibrinogen was used for the blot shown in panel B. Molecular weight standards are shown in kilodaltons. Bands seen on FALP lanes of antifibrinogen blot (B) correspond to the size of fragment X (X). For this preparation, EACA was used only for the first column chromatography but not for the subsequent chromatographic steps. Therefore, the size of the fibrinogen fragment is bigger than that of the FALP prepared in the absence of EACA shown in Figure 2. The blot was overexposed to visualize the fibrinogen band in sFALP lane.