The Warsaw Treaty Organization (also known as the Warsaw Pact) was a political and military alliance established on May 14, 1955 between the Soviet Union and several Eastern European countries.
1 Donors with blood type A... can donate to recipients with blood types A and AB. 2  Donors with blood type B... can donate to recipients with blood types B and AB.  Donors with blood type AB...
Donors with type O- red blood cells are referred to as universal donors and their red blood cells can be given to any other blood type. Donors with type AB+ are referred to as universal recipients and can receive red blood cells from any other blood type. Donors with type AB- are universal plasma donors and can give plasma to any other blood type.