Regulation of CD69 expression on eosinophil precursors by interferon-gamma

The purpose of this study was to determine whether interferon-gamma (IFN-gamma) induced CD69 expression by eosinophil precursors, Eosinophil precursors were induced from CD34+ cord blood cells using recombinant human interleukin-3 (IL-3) and interleukin-5 (IL-5), On day 14 of culture, cells constitutively expressed CD69 and the IFN-gamma receptor (IFN-gamma R), Stimulation with IFN-gamma for 24 h did not affect IFN-gamma R expression by the cells, On the other hand, IFN-gamma significantly upregulated CD69 expression by the precursors after 24 h of incubation. A specific JAK2 inhibitor (AG-490) caused a concentration-dependent suppression of IFN-gamma-induced CD69 expression by the precursors. In conclusion, these results indicate that IFN-gamma induces CD69 expression by eosinophil precursors via the activation of JAK2, Copyright (C) 2000 S. Karger AG, Basel.