In Vivo Aging of Transfused Erythrocytes and 2,3-Diphosphoglycerate Levels

Levels of 2,3-diphosphoglycerate (2,3-DPG) and oxygen affinity were measured in a patient with refractory congenital hypoplastic anemia in order to determine the response of aging transfused erythrocytes to a decrease in tissue oxygen tension. Ferrokinetic studies revealed that the rate of erythropoiesis after transfusion was approximately 10% of normal. In the interval between transfusions, the level of 2,3-DPG and P₅₀ rose to values considerably above the normal range as the level of the hematocrit decreased. On five separate occasions, the 2,3-DPG concentration was elevated (average 25.5 µmoles/g of hemoglobin) and the P₅₀ level increased (average 33.2 mm of mercury) 24 hr prior to transfusion. It is concluded that in vivo aging of transfused erythrocytes does not prevent these cells from responding to an increasingly hypoxic environment by elevating 2,3-DPG levels and by decreasing oxygen affinity.