Factor VIII (formerly referred to as antihemophilic globulin and Factor VIIIc) is a large glycoprotein (320kD) that circulates in plasma at approximately 200ng/ml. Synthesized in the liver, the majority of Factor VIII is cleaved during expression resulting in a heterogeneous mixture of partially cleaved forms of F.VIII ranging in size from 200-280kD. The F.VIII is stabilized by association with von Willebrand Factor to form a F.VIII-vWF complex required for normal survival of F.VIII in vivo (T1/2 of 8-12 hours).F.VIII is a pro-cofactor that is activated through limited proteolysis by thrombin. I n this process F.VIIIa dissociates from vWF to combine with activated Factor IX, calcium and a phospholipid surface where it is an essential cofactor in the assembly of the Factor X activator complex. Once dissociated from vWF, F.VIIIa is susceptible to inactivation by Protein C and by non-enzymatic decay. Hemophilia A is a congenital bleeding disorder resulting from an X-chromosome linked deficiency of F.VIII. The severity of the deficiency generally correlates with the severity of the disease. Some hemophiliacs (~10%) produce a F.VIII protein that is partially or totally inactive. The production of neutralizing antibodies to F.VIII also occurs in 5-20% of hemophiliacs.Kit Components:F0016-25A: Capture Antibody 1x400ul Polyclonal affinity-purified anti-FVIII:C IgG for coating plates.F0016-25B: Detection Antibody 4x10ml of prediluted HRP-conjugated polyclonal anti-F.VIII antibody for detection of captured F.VIII.F0016-25C: Sample Diluent 1x 100ml green colored diluent optimized for dilution of samples.Storage and Stability:May be stored at 4°C. For long-term storage, aliquot and store at 4°C. Do not freeze. Aliquots are stable for at least 12 months. For maximum recovery of product, centrifuge the original vial prior to removing the cap. Further dilutions can be made in assay buffer.
