Regulation of CD69 Expression on Eosinophil Precursors by Interferon-γ.

The purpose of this study was to determine whether interferon-γ (IFN-γ) 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-γ receptor (IFN-γR). Stimulation with IFN-γ for 24 h did not affect IFN-γR expression by the cells. On the other hand, IFN-γ 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-γ-induced CD69 expression by the precursors. In conclusion, these results indicate that IFN-γ induces CD69 expression by eosinophil precursors via the activation of JAK2.Copyright © 2000 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]