Diego Isoantigens

Diego isoantigens are the antigens responsible for encoding isoimmunoglobulin. Diego isoantigens are patterns of isoalbumin and fetal erythroglobin groups. Isolated from human placental sera in 1925 by the German immunologist D. Hirschfield (1874-1946).

In infants, antigen 55 cross-coagulates with group plasma antigens of human gametophobes of group A (isotypes I and II); and in the sera of pregnant people with blood group B (III and IV isotypes