Ashby technique
Encyclopedia
The Ashby technique is a method for determining the volume and life span of red blood cells in humans, first published by Dr. Winifred Ashby
in 1919. The technique involves injection of compatible donor red blood cells of a different blood group into a recipient, followed by blood testing periodically afterwards. Differential agglutination
of the red cells is then used to determine the number of remaining donor cells, allowing the survival rate to be determined. It does not involve radioisotope technology, and was the first technique to successfully establish the correct red blood cell life span. In particular, Type O blood
is first transfused into Type A or B
subjects. In subsequent blood samples, the patient's own A and B blood cells are removed by agglutination with either anti-A or anti-B serum
. The number of remaining nonagglutinated Type O cells as a function of time defines the survival rate of blood cells. This technique was used extensively during World War II and shortly after but has more recently been replaced by techniques that label one's own blood, due of the dangers of using donor blood.
Winifred Ashby
Dr. Winifred Ashby was a British-born American pathologist known for developing the Ashby technique for determining red blood cell survival.- Biography :...
in 1919. The technique involves injection of compatible donor red blood cells of a different blood group into a recipient, followed by blood testing periodically afterwards. Differential agglutination
Agglutination (biology)
Agglutination is the clumping of particles. The word agglutination comes from the Latin agglutinare, meaning "to glue."This occurs in biology in three main examples:...
of the red cells is then used to determine the number of remaining donor cells, allowing the survival rate to be determined. It does not involve radioisotope technology, and was the first technique to successfully establish the correct red blood cell life span. In particular, Type O blood
ABO blood group system
The ABO blood group system is the most important blood type system in human blood transfusion. The associated anti-A antibodies and anti-B antibodies are usually IgM antibodies, which are usually produced in the first years of life by sensitization to environmental substances such as food,...
is first transfused into Type A or B
ABO blood group system
The ABO blood group system is the most important blood type system in human blood transfusion. The associated anti-A antibodies and anti-B antibodies are usually IgM antibodies, which are usually produced in the first years of life by sensitization to environmental substances such as food,...
subjects. In subsequent blood samples, the patient's own A and B blood cells are removed by agglutination with either anti-A or anti-B serum
Blood serum
In blood, the serum is the component that is neither a blood cell nor a clotting factor; it is the blood plasma with the fibrinogens removed...
. The number of remaining nonagglutinated Type O cells as a function of time defines the survival rate of blood cells. This technique was used extensively during World War II and shortly after but has more recently been replaced by techniques that label one's own blood, due of the dangers of using donor blood.