IFN-α inhibits generation of DiOC₆^low/HE⁺ clonal Th2 cells.

CD3⁻CD4⁺ cells from hypereosinophilic patient 1 were cultured for 24 hours in the absence or presence of sFasL (25 ng/mL). IFN-α (10⁴ IU/mL) was added at the beginning of the culture. At the end of the culture, cells were stained for 15 minutes at 37°C with DiOC₆ or HE followed by flow cytometry analysis. The histograms represent DiOC₆ (upper) and HE (lower) staining of Th2 cells obtained from patient 1 after 24 hours of culture in the absence (solid lines) or presence (broken lines) of IFN-α.