Characterization and functional studies of vWF A3 domain monoclonal antibodies that inhibit binding of vWF to collagen / 中华血液学杂志

ABSTRACT

<p><b>OBJECTIVE</b>To prepare anti-von Willebrand factor A3 (vWF-A3) domain monoclonal antibodies(mAbs) which block vWF-A3 binding to collagen, and characterize their biochemical properties and functions.</p><p><b>METHODS</b>BALB/c mice were immunized with purified recombinant vWF-A3 protein (rvWF-A3). Murine anti-human vWF-A3 mAbs were developed by standard hybridoma technology and identified with ELISA. The recognition of the mAbs with rvWF -A3 and reduced human vWF was identified by Western-blot. The effect of mAbs on binding of purified human vWF to human placenta or calf skin collagen III was studied with collagen binding inhibition test.</p><p><b>RESULTS</b>A group of 30 murine anti-human vWF-A3 mAbs was obtained, from which 2 clones were identified as inhibitory ones and designated as SZ-123 and SZ-125. SZ-123 and SZ-125 could react specifically with human vWF and rvWF-A3 respectively, while neither of them reacted with rvWF-A1 and rvWF-A2. Western-blot showed that SZ-123 and SZ-125 could recognize a 27 x 10(3) band of rvWF-A3 and 2 reduced human vWF bands at 250 x 10(3) and 170 x 10(3). SZ-123 and SZ-125 not only inhibited the binding of purified human vWF (1.5 and 3.0 microg/ml) to human type III collagen and to calf skin collagen III in a dose dependent manner, but also inhibited the binding of plasma vWF from human, rhesus monkeys or Beagle dogs to the two collagens.</p><p><b>CONCLUSION</b>SZ-123 and SZ-125 are neutralizing mAbs against vWF-A3 domain and may have therapeutic potential as an antithrombotic agent.</p>