Autori: Mitrofan-Oprea L., Palii C., Tissier J-P., Héron A., Verpoort T., Behague M. , Goudaliez F., Smagghe E., Schooneman, F. Huart J-J., Montreuil J., Bratosin D

Editorial: Transfus. Clin. Biol. , 14, p.393-401, 2007.

Rezumat:

In light of recent results on the mechanism of programmed cell death of human red blood cells (RBC), the aim of the present study was to solve
the enigma of the rapid clearance of transfused RBCs.
Materials and methods: We describe new criteria of RBC viability founded on the use of flow cytometry. They were applied, in association with
the classical ones: ATP and hemolysis measurements, to RBCs stored in SAGM medium for 42 days.
Results and conclusions: Application of an original method of flow cytometric quantitation of in vitro erythrophagocytosis showed that an
important proportion of stored RBCs were phagocytized although the following classical signals for phagocytosis were absent, i.e.: desialylation,
phosphatidylserine exposure in the outer leaflet of the RBC membrane, loss of CD47 receptor, an antiphagocytosis signal. In addition, ATP was still
present and hemolysis was very low. This enigma was solved by the use of scanning electron microscopy, which showed the disappearance of
discocytes and the presence of an important proportion of spheroechinocytes, which are the phagocytable forms of RBCs. The mechanism of this
dramatic morphological transformation remains to be elucidated.

Cuvinte cheie: Erythrocytes, Red blood cell, Transfusion, Erythrophagocytosis, Flow cytometry, Cell viability