The importance of warming at 37 degrees C for removal of leukocytes and platelets from reconstituted red cells.

Red cells suspended in sodium phosphate buffer (R-RBC) were incubated at 37 degrees C, and the distribution of the leukocytes and platelets in the suspension was compared to a similar suspension incubated at 22 degrees C. Following centrifugation, a more dense packing of the red cells was observed in warm R-RBC, and less leukocytes and platelets remained in the red cells below the buffy coat, than was observed in R-RBC packed at room temperature. These experiments indicate that incubation at 37 degrees C prior to separation improves the quality of leukocyte- and platelet-depleted red cells.