It is quite clear that B-cell epitopes on intact, native protein antigens in solution are of the discontinuous type whether defined structurally or functionally. It is also clear that although B-cell epitopes share a number of common features, they can only be defined in detail in terms of the individual antibody with which they react and in terms of the method used to describe them. Therefore, in order to ensure open communication and eliminate misunderstanding between individual investigators, it is wise to clearly state the conditions under which the epitope is defined. Given these conditions, one can view protein antigenicity in terms of the multideterminant, regulatory hypothesis presented some years ago. This hypothesis states that "The surface of a protein consists of a complex array of overlapping potential antigenic determinants; in aggregate these approach a continuum. Most determinants depend upon the conformational integrity of the native molecule. Those to which an individual responds are dictated by the structural differences between the antigen and the host's self-proteins and by host regulatory mechanisms, and are not necessarily an inherent property of the protein molecule reflecting restricted antigenicity or limited antigenic sites".