REVERSAL OF STORAGE-RELATED MORPHOLOGICAL CHANGES IN RED BLOOD CELLS: WHAT IS THE IMPACT IN THE MICROCIRCULATION
Robert Flower1,2, Marie Anne Balanant1,2, Melinda Dean1,2, Emilie Sauret2, Suvash Saha2, Yuan-Tong Gu2
1Australian Red Cross Blood Service, Australia;
2Queensland University of Technology, Australia
The re-introduction of stored red blood cells (RBC) to the physiological environment following transfusion is a complex process. To minimise haemolysis, storage solutions are hypertonic. During storage RBC undergo morphological transformation from biconcave discocytes to stomatocytes. The shape change during storage and the extent to which this shape change can be reversed when RBC are returned to the physiological plasma environment was investigated.
The morphology of RBC stored in a “SAGM” a hypertonic solution was examined microscopically weekly for 6 weeks. At each time point RBC were equilibrated for 2 hours, at room temperature (RT) in compatible donor plasma. For each pack tested and each time point the size and shape of RBC were evaluated by microscopy for more than 200 RBC.
“Spiky” echinocytes were evident from day 23 of storage these, however represented <10% of the RBC. A majority of RBC maintained a discocytic or curved stomatocytic morphology. When reconstituted in plasma, from day 23 onwards >70% of RBC assumed an echinocyte morphology and cell diameter was reduced.
The majority of RBC maintained a discocytic or stomatocytic morphology when stored in SAGM . Shape changes were observed when RBC were reintroduced cells to a physiological environment. After 23 days of storage, the majority of RBC returned to a physiological environment adopted an echinocyte morphology a change likely to change the behaviour of RBC in the microcirculation. Examination of the level of reconstitution of functions when RBC returned to a physiological environment provides a measure of RBC quality, and the utility of transfusion, that is more likely to reflect behaviour in the capillary microcirculation and, ultimately, clearance in the spleen.