The effect of continuous G-CSF application in human cyclic neutropenia: a model analysis

Br J Haematol. 1995 May;90(1):41-7. doi: 10.1111/j.1365-2141.1995.tb03378.x.


Human cyclic neutropenia (CN) is a rare haematological disorder characterized by oscillations of blood neutrophils at subnormal levels with a stable period of approximately 21 d. During the phase of severe neutropenia (neutrophils < 250 cells/microliters), which last 4-10 d, the patients are endangered by serious infections. Several authors report that continuous G-CSF application can elevate the blood neutrophils to such a level that the risk of infections is significantly reduced. Although the characteristic cycles are not eliminated by G-CSF, the period of the oscillations is shortened to 12-14 d. Based on a previously proposed computer-simulation model of human CN, the effects of continuous G-CSF application on CN are studied. It is shown how the known different cell-kinetic effects of G-CSF on granulopoiesis explain the clinical data in CN. The reduced length of the cycles emerges as a result of the transit time reduction of the post-mitotic granulopoietic cells by G-CSF. The measured increase of the neutrophil maxima is reproduced by the additional mitoses of the immature granulopoietic bone marrow cells induced by G-CSF. The slight elevation of the neutrophil nadirs can be attributed to a weak effect of G-CSF on the assumed underlying defect in CN (an abnormally small variance of the granulopoietic bone-marrow transit time).

MeSH terms

  • Cell Cycle
  • Computer Simulation*
  • Dose-Response Relationship, Drug
  • Drug Administration Schedule
  • Granulocyte Colony-Stimulating Factor / administration & dosage*
  • Hematopoiesis
  • Humans
  • Models, Biological*
  • Neutropenia / therapy*
  • Periodicity
  • Time Factors


  • Granulocyte Colony-Stimulating Factor