Studies on the Human Red Cell Agglutinins of the Swan Mussel (Anodonta cygnea)

Summary. Extracts of the swan mussel Anodonta cygnea specifically agglutinated enzyme treated human erythrocytes of phenotypes A 1 , A 2 , B, A 1 B and A 2 B. Absorption with A 2 or B cells left a specific agglutinin for A 1 cells, but separable agglutinins against A and B cells could not be demonstrated. Of 29 sugars tested in parallel with anti‐A from Helix aspersa , only lactose inhibited the A. cygnea agglutinins, whereas the H. aspersa anti‐A was inhibited by N‐acetyl‐d‐galactosamine, N‐acetyl‐d‐glucosamine, raffinose and stachyose.