MoAb F-104 species specificity. Nonreducing and reducing SDS-PAGE (8% and 10% gels, respectively) and F-104 immunoblotting (PVDF transfers) were conducted as described in the text. Approximately 5 μg fibrinogen were applied to each lane for Amido Black-stained transfers and 2.5 μg for F-104 epitope localization, as follows: HU (human), EQ (equine), BO (bovine), RA (rabbit), and MU (murine). The migration of standard molecular weight markers is indicated at the left of each panel. The weak band of immunoreactivity observed for murine fibrinogen (top) is nonspecific and reflects binding of the HRP conjugate to contaminating IgG in this preparation; the same profile was obtained when the F-104 incubation step was omitted.