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The apoptosis of blood polymorphonuclear leukocytes in sickle cell disease

Hakan Ozdogu1, Can Boga, Oktay Sozer

  • 1Department of Hematology, Faculty of Medicine, Baskent University, Ankara, Turkey.

Cytometry. Part B, Clinical Cytometry
|November 18, 2006
PubMed
Abstract

Insights

Altered polymorphonuclear leukocyte (PMN) apoptosis in sickle cell disease (SCD) patients may contribute to vasoocclusion. This is likely due to inflammatory mediators, not nitric oxide levels.

Area of Science:

  • Hematology
  • Immunology
  • Cell Biology

Background:

  • Apoptosis of human polymorphonuclear leukocytes (PMNs) in sickle cell disease (SCD) is not well understood.
  • Investigating PMN apoptosis in SCD patients is crucial for understanding disease pathogenesis.

Purpose of the Study:

  • To examine and quantify PMN apoptosis in patients with SCD.
  • To compare PMN apoptosis in SCD patients during and after vasoocclusive crisis with healthy controls.

Main Methods:

  • Flow cytometry was used to quantify PMN apoptosis.
  • Annexin-V and propidium iodide (PI) staining assessed early and late apoptotic cells.
  • Plasma nitric oxide concentrations were measured in SCD patients.

Main Results:

  • PMN apoptosis (early and late) was significantly higher in SCD patients compared to controls.
  • Dead cells (PI staining) were elevated in SCD patients after crisis.
  • No significant difference in PMN apoptosis was observed between SCD patients during and after crisis.
  • Plasma nitric oxide levels did not correlate with PMN apoptosis in SCD patients.

Conclusions:

  • Altered PMN apoptosis in SCD patients may contribute to vasoocclusive mechanisms.
  • Inflammatory mediators, rather than nitric oxide, are likely responsible for PMN apoptosis changes in SCD.

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