Abstract: The invention provides a method of detecting a class of substances, by providing an assay configuration which allows for reaction with a homologous portion common to all members of the class. The configuration utilizes a capture reactant to immobilize class members, revealing previously unrecognizable reaction sites on the class. The capture reactant interacts with a homologous portion on the class members. The immobilized class is then detected, such as by the use of a sandwich antibody directed to another homologous portion of the class now exposed for reaction, or directed to specific portions of specific members of the class that have been exposed for reaction. These reaction sites were unrecognizable prior to immobilization of the class members with the capture reactant.

Abstract: The subject invention provides an antibody directed to von Willebrand factor antigen characterized by being capable of recognizing an epitope of the von Willebrand factor antigen, the epitope being evolutionarily conserved among vertebrate species. The subject invention further provides a method for the qualitative and quantitative detection of von Willebrand factor in multiple species using an enzyme-linked immunosorbent assay and the antibodies of the subject invention.

Abstract: Novel polyclonal antibodies useful for measuring von Willebrand Factor in plasma of various vertebrate species either qualitatively or quantitatively, methods of producing and using such antibodies and kits containing them are described.