Cytokine profile during high-dose rhG-CSF therapy in severe congenital neutropenia

The effect of recombinant human granulocyte colony-stimulating factor (rhG-CSF) on cytokine profile was evaluated in a case of severe congenital neutropenia. The plasma levels of cytokines were measured before and during rhG-CSF therapy. These included G-CSF, granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin-1 alpha, interleukin-1 beta, interleukin-2 (IL-2), interleukin-3 (IL-3), interleukin-4, interleukin-6 (IL-6), and tumor necrosis factor-alpha. Soluble interleukin-2 receptor (sIL-2R) was measured serially during rhG-CSF therapy. Lymphocyte subpopulations including CD2, CD3, CD4, CD8, CD19, CD20, and CD25 were also measured, rhG-CSF was administered once daily as a 30-min infusion. The patient was treated with increasing dose levels of 100, 200, 400, 800, and 1,600 micrograms/m2/day. The level of endogenous G-CSF was elevated to 334 pg/ml before treatment and GM-CSF, IL-2, IL-3, and IL-6 were slightly elevated. Clinically, he showed a moderate response to a high dose of rhG-CSF (1,600 micrograms/m2/day). Plasma levels of G-CSF markedly increased during therapy but plasma levels of other cytokines did not show significant changes during therapy and lymphocyte subpopulations did not significantly change. A drastic increase in sIL-2R expression was observed after rhG-CSF infusion and an increase in sIL-2R expression occurred even before a major increase in granulocyte counts. These results showed that a high dose rhG-CSF therapy may influence the cytokine network as judged by the increased sIL-2R expression.