Development and applications of surface plasmon resonance-based von Willebrand factor-collagen binding assay.
Von Willebrand factor (vWf) functions both as a carrier of factor VIII (fVIII) in plasma and as an adhesive protein providing the primary link between collagen of the extracellular matrix and platelets sequestered from blood flow. The functional activity of vWf correlates with the level of its binding to collagen, which is commonly measured in the enzyme-linked immunosorbent assay (ELISA). We developed an automated collagen-binding assay employing the surface plasmon resonance (SPR) phenomenon, which allows one to quantitatively measure the binding of purified vWf and vWf-containing therapeutic fVIII concentrates to collagen type III immobilized on a biosensor chip. The results of the SPR-based assay highly correlated (r = 0.987) with collagen-binding ELISA. The advantages of the SPR-based assay are its higher accuracy and reproducibility in comparison with ELISA. We applied the developed assay for monitoring structural changes in the vWf component of plasma-derived fVIII/vWf concentrates during a virus inactivation procedure performed by heat treatment. We determined the critical residual moisture content of 2% that can be present in lyophilized concentrates during heat-treatment procedures without causing deteriorative changes in vWf properties. Our data suggest that the SPR-based assay is a useful tool in the development of industrial virus-inactivation procedures, allowing one to preserve vWf activity and achieve the maximal therapeutic efficacy of fVIII/vWf concentrates.
Saenko
Evgueni
E
Holland Laboratory, American Red Cross, Rockville, Maryland 20855, USA. saenko@usa.redcross.org
Kannicht
Christoph
C
Loster
Klemens
K
Sarafanov
Andrey
A
Khrenov
Alexey
A
Kouiavskaia
Diana
D
Shima
Midori
M
Ananyeva
Natalya
N
Schwinn
Horst
H
Gruber
Gerhard
G
Josic
Djuro
D
D001665:Binding Sites; D001681:Biological Assay / Q000379:methods; D015374:Biosensing Techniques / Q000295:instrumentation; D002352:Carrier Proteins / Q000032:analysis / Q000378:metabolism; D024061:Collagen Type III / Q000378:metabolism*; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D005169:Factor VIII / Q000378:metabolism*; D006801:Humans; D007700:Kinetics; D015203:Reproducibility of Results; D020349:Surface Plasmon Resonance / Q000379:methods*; D014841:von Willebrand Factor / Q000032:analysis* / Q000378:metabolism
D002352:Carrier Proteins; D024061:Collagen Type III; D014841:von Willebrand Factor; D005169:Factor VIII