Changes in Membrane Fluidity of Blood Platelets in Myeloid Neoplasm

Abstract

In this study we evaluate the alterations in membrane fluidity of blood platelets in patients with various entities of myeloid malignancies.The clinical history of myeloproliferative and myelodysplastic disorders is often complicated by thromboembolic or hemorrhagic events.The mechanism of these major complications remains unclear. Since there is a weak correlation between the risk of these life threatening complications and the number of blood platelets, our research is focusing on qualitative defects of platelets.Membrane fluidity is an important parameter which influences many of the unique cellular functions and which is strongly correlated (among other factors) to the membrane lipid composition. We try to correlate changes in cell membrane fluidity with the clinical status of the patient disease.32 patients with various entities of myeloid neoplasm were selected (Department of Hematology, Emergency University Hospital of Bucharest). They were diagnosed according to the WHO criteria. 11 normal healthy volunteers, non smokers, drug-free, were used as controls.Membrane fluidity was assessed by fluorescence anisotropy measurements. The platelet membrane shows to be more rigid compared with controls/normal regardless of the clinical type of myeloproliferative disorder. However patients with severe clinical status due to acute myeloid leukemia have a more fluid membrane compared to the same patients found previously in a better state. Thus, the activity (or severity) of the disease correlates with the increase in membrane fluidity, as other studies revealed on lymphocytes. We consider that detection of these modifications may be useful for a better insight in cell abnormalities occurring in this pathology.