In: Biology
A mother has two children. The first was born perfectly healthy while the second one was born with rashes, showed clumping and lysis of blood. Based upon this information how would you classify this disorder? What type of antibody-antigen interaction is this and why? Explain how this disorder arises.
This type of disorder is usually called Hemolytic anemia of newborn or Erythroblastosis fetalis. In this disorder, antibodies are developed against Rh antigen present on the surface of RBCs of the fetus.
During the first pregnancy, the Rh-negative mother carrying Rh-negative fetus in the womb doesn't produce antibodies. But the
Rh-negative mother carrying Rh-positive fetus in the womb produces antibodies against the RBCs of the fetus.
Therefore due to the significant separation between mother and fetus by the placenta antibodies do not pass to the fetus during the first pregnancy.
But during the second pregnancy, the placenta is not able to well separate the Rh-ve mother carrying the Rh-positive fetus, therefore during delivery, the antibodies pass to the baby through the placenta and bind to the Rh antigen on RBCs. The binding of the antibody to the Rh Antigen leads to the clumping reaction and its lysis thereby causing hemolytic anemia.
The name itself suggests Heme= red part of RBCs, Lytic = lysis
so prevent the baby from this disorder, RhoGAM injection is given which are the antibodies against Anti-Rh