The Comparison of 2-Chlorodeoxyadenosine (2-Cd A) in Combination with Interferon α (IFN α) or Interferon γ (IFN γ) on Granulocyte-Macrophage Progenitor Cells (CFU-GM) and Clonogenic Blasts in (CFU-L) In Vitro Cultures

Abstract

In the present in vitro study we investigated the influence of 2-chlorodeoxyadenosine (2-CdA) and interferon γ (IFNγ) on the clonal growth of granulocyte macrophage progenitor (CFU-GM) cells from 10 normal individuals and from 10 patients with chronic myeloid leukemia (CML) and on CFU-L blasts from 10 patients with acute myeloid leukemia (AML). 2-CdA was added to the culture medium at 20 nM/1, 40nM/1 and 80nM/1 concentrations and IFNγ at concentrations of 10²U/ml, 10³U/ml and 10⁴U/ml. Both agents were used alone and in combination with these different concentrations. We observed a decrease in the number of colonies formed by CML CFU-GM as well as by AML CFU-L in a dose-dependent manner. The drugs used alone inhibited to a higher degree the growth of CML than of normal CFU-GM progenitors. 2-CdA and IFN γ showed the greatest additive effect on the growth of CFU-L blasts at the concentrations of 80nM/1 and 10⁴U/ml, respectively. We compared our results with previous in vitro studies in which we have demonstrated the synergistic inhibitory effect of 2-CdA and IFN α on both normal and leukemic hematopoiesis. We suggest that the greatest inhibitory effect is observed when 2-CdA and IFN α at the highest concentration are added together to the culture of AML CFU-L blasts.

Key Words:

• 2-chlorodeoxyadenosine
• interferon α
• interferon γ
• acute myeloid leukemia
• chronic myeloid leukemia
• cultures in vitro