Monosaccharides define two immunodominant structures of chicken fetal antigen.

Chicken fetal antigen (CFA) is an oncodevelopmental antigen associated with hematolymphoid development and differentiation. The immunodominant structures of two CFA determinants were characterized by hapten inhibition of microcytotoxicity (HIM) and were found to be defined by specific monosaccharides. CFA determinants 5 and 11 were effectively (greater than 50%) inhibited by D-mannose and D-glucose, respectively. Therefore, these carbohydrate residues, or closely related structures, are proposed as the immunodominant structures for these antigenic determinants. Implications of these results vis à vis the developmental control and biological role of CFA are discussed.