Dolichos biflorus agglutinin is a glycoprotein with a molecular weight of about 111 kDa and consists of 4 subunits of approximately equal size. This lectin has a carbohydrate specificity toward α-linked N-acetylgalactosamine. It has been used to establish secretor status in blood group A individuals by hemagglutination inhibition techniques and for blood typing. 

DBA has been used as a general marker of developing renal collecting ducts, which can then be used to establish secretion status in blood group A individuals by hemagglutination inhibition and for detecting blood typing. DBA is over thousand times more active in agglutinating blood group A1 cells versus A2 cells, and is used to distinguish these blood types in routine serology applications, and has potential applications in examining tumors which affect the levels of blood group substances.