Abstract
The mechanism of antigen formation in blood dyscrasias associated with antibodies to drugs has, up till now, remained obscure. The characteristics of the classical Landsteiner system, in which the complete antigen is formed by union of the drug to protein by covalent bonds, do not apply in this case.
As a result of the present experimental study, an hypothesis based upon the union of drug to cell by hydrogen bonds is postulated to account for certain otherwise unexplained observations.
In addition, the investigation of the patterns of cross-reactivity of PAS-dependent haemagglutinating antibodies in sera from two patients allergic to this compound revealed the presence of two distinct antigenic determinants.