The direct effect of interferon-gamma on human eosinophilic leukemia cell lines: the induction of interleukin-5 mRNA and the presence of an interferon-gamma receptor.

The EoL-1 and EoL-3, human eosinophilic leukemia cell lines, have been used as models for studying the maturation and the function of human eosinophils. We investigated the effects of interferon-gamma (IFN-gamma) on superoxide anion (O2-) production of these cell lines and interleukin-5 (IL-5) mRNA expression in the EoL-1. O2- was measured by chemiluminescence of MCLA, one of cypridina luciferin analogs. The O2- production of fMLP-stimulated EoL-1 and EoL-3 was increased by the IFN-gamma treatment. IL-5 mRNA expression was detected in the IFN-gamma-treated EoL-1 by reverse transcription-polymerase chain reaction (RT-PCR). Further, we examined IFN-gamma receptor 1 mRNA expression in these cell lines and peripheral blood eosinophils by means of northern blot hybridization. IFN-gamma receptor 1 mRNA was detected in the EoL-3 and the IFN-gamma-treated EoL-1. A weak expression of IFN-gamma receptor 1 mRNA was detected in peripheral blood eosinophils isolated from a patient with eosinophilia. These results suggest that IFN-gamma may act on eosinophils directly through its receptor.