Canine blood groups

Blood groups defined by different antigens on the surface of red blood cells are present in all mammals. In dogs the blood type is controlled by five different independent loci, their clinical significance in transfusion medicine is less pronounced and their allele frequencies can vary greatly between the different races. In total, over 30 different possible blood groups found there.

Clinically, the first transfusion in dogs is usually unproblematic. On subsequent transfusions or in dogs with an unknown history, however, it is essential to pay attention to the compatibility of blood groups in order to avoid potentially life-threatening transfusion reactions.

Nomenclature

In the past six blood groups were distinguished and designated by letters in the literature, but this is now obsolete. The current system assigns each series to a DEA number, the abbreviation " DEA " stands for Dog Erythrocyte antigens. Each DEA Series conforms to a genetic locus. For transfusion -related groups are given in the following table:

DEA 1.0 - series

The DEA 1.0 -series comes in four alleles ( 1.1, 1.2, 1.3, and zero), leading to four possible phenotypes of the same name. There is a linear dominance between these alleles; 1.1 is the most dominant, the zero rezessivste allele. A dog with 1.1 phenotype may thus have the genotypes 1.1/1.1, 1.1/1.2, 1.1/1.3 or 1.1/Null.

There are no naturally occurring antibodies against the alleles of DEA 1.0 series. DEA 1.1 negative dogs that have received a DEA 1.1 - positive transfusion are, but become more sensitive and can react with a hemolysis when re- transfusion of DEA 1.1 positive blood. Also DEA 1.1 -negative females can trigger a maternally induced hemolysis (analogous to the Rh factor in man; hypersensitivity reaction type II ) after sensitization with their DEA 1.1 -positive puppies. Clinically relevant, however, this mechanism seems to be only in bitches that have been sensitized by a blood transfusion.

DEA 3.0 - series

The DEA 3.0 - series contains the alleles 3.0 and zero, with 3.0 above zero is dominant. There are of course occurring antibodies; receives a zero / zero dog blood by phenotype 3.0, the erythrocytes obtained are eliminated within 3-5 days.

The 3.0 - phenotype is rare, but occurs more frequently at Greyhounds and Japanese dog breeds.

DEA 4.0 - series

The DEA 4.0 - series contains the alleles 4.0 and zero, with 4.0 above zero is dominant. In the (very rare ) zero / zero dogs naturally occurring antibodies exist against blood phenotype 4.0, which does not seem to be clinically relevant. DEA 4.0 positive dogs that are negative for all other series, are considered universal donor.

DEA 5.0- series

The DEA 5.0- series contains the alleles 5.0 and zero, with 5.0 above zero is dominant. DEA 5.0 positive dogs are rare; natural antibodies occur in negative dogs. If a zero / zero dog blood by phenotype 5.0, the erythrocytes obtained are eliminated within 3-5 days.

DEA 7.0 - series

The DEA 7.0 - series contains the alleles 7.0 and zero, with 7.0 above zero is dominant. Maybe next still exists an additional allele. 7.0 DEA is not a real surface antigen of red cells, but is produced in the tissue and absorbed by the red blood cells -, therefore, the 7.0 - state does not change even after a bone marrow transplant.

Of course, the majority of the zero / zero dogs has occurring antibodies against the 7.0 phenotype. Such dogs received 7.0 eliminate erythrocytes after a few days, with elimination compared with the 3.0 and 5.0 series is slowed.