A monoclonal antibody to von Willebrand factor (vWF) inhibits factor VIII binding. Localization of its antigenic determinant to a nonadecapeptide at the amino terminus of the mature vWF polypeptide. - Bahou, WF; Ginsburg, D; Sikkink, R; Litwiller, R; Fass, DN (J Clin Invest, 1989)