Hemolytic disease of the newborn is caused by antibodies against which major blood group antigen?


a. MHC protein
b. MN antigen
c. ABO antigen
d. rhesus antigen
e. type II protein

Verified step by step guidance

1. Understand the context of hemolytic disease of the newborn (HDN), which occurs when there is an incompatibility between the blood types of the mother and the fetus.
2. Identify that HDN is primarily caused by the mother's immune system producing antibodies against fetal red blood cells.
3. Recognize that the most common cause of HDN is related to the Rh factor, a specific protein found on the surface of red blood cells.
4. Recall that the Rh factor is also known as the rhesus antigen, which is a major blood group antigen.
5. Conclude that the antibodies responsible for HDN are typically against the rhesus antigen, making option 'd' the correct choice.

Key Concepts

Hemolytic Disease of the Newborn (HDN)

Hemolytic disease of the newborn occurs when maternal antibodies cross the placenta and attack fetal red blood cells, leading to hemolysis. This condition is often associated with blood group incompatibility, particularly when the mother is Rh-negative and the fetus is Rh-positive. Understanding the mechanisms of antibody production and the immune response is crucial for grasping how HDN develops.

Rh Factor

The Rh factor is a major blood group antigen that can lead to incompatibility between a mother and her fetus. If an Rh-negative mother carries an Rh-positive baby, her immune system may produce antibodies against the Rh antigen, resulting in hemolytic disease. The Rh factor is significant in prenatal care, as it necessitates monitoring and potential interventions to prevent HDN.

Blood Group Antigens

Blood group antigens, such as ABO and Rh antigens, are specific molecules found on the surface of red blood cells that determine an individual's blood type. These antigens can trigger immune responses if foreign to the body, leading to conditions like hemolytic disease. Knowledge of these antigens is essential for safe blood transfusions and understanding maternal-fetal blood group interactions.