Blood Types and Antigens Overview

Study Notes

Blood types are determined by antigens present on the surface of red blood cells (RBCs).
Antigens A and B are the primary determinants of blood type.
Blood type A has the A antigen.
Blood type B has the B antigen.
Blood type AB has both A and B antigens.
Blood type O has neither A nor B antigens.

Antibodies, also known as agglutinins, are present in blood plasma.
Blood type A has anti-B antibodies.
Blood type B has anti-A antibodies.
Blood type AB has no antibodies.
Blood type O has both anti-A and anti-B antibodies.
Blood transfusions are successful when the recipient's plasma does not contain antibodies against the donor's blood type.
Hemolysis occurs when RBCs burst due to antibody-antigen reactions during incompatible transfusions.

Type O blood is considered the universal donor because it lacks both A and B antigens, avoiding reactions with recipient antibodies.
Type AB blood is the universal recipient because it lacks antibodies, allowing it to receive any blood type without reactions.

Blood is also classified as Rh positive or Rh negative based on the presence or absence of the Rh antigen.
Rh positive blood has the Rh antigen.
Rh negative blood lacks the Rh antigen.

Rh incompatibility can occur in two scenarios:
- Blood transfusion: When an Rh-negative individual receives Rh-positive blood, antibodies against the Rh antigen develop.
- Pregnancy: An Rh-negative mother carrying an Rh-positive fetus can develop anti-Rh antibodies, potentially harming future pregnancies.

Type A blood:
- Recipient: A, AB
- Donor: A, O
Type B blood:
- Recipient: B, AB
- Donor: B, O
Type AB blood:
- Recipient: A, B, AB, O
- Donor: AB, O
Type O blood:
- Recipient: O
- Donor: O
Important Note: This summary is for basic understanding only. Medical professionals must verify blood type compatibility for safe transfusions.