J1 and J2 protein expression is influenced by GM-CSF. (A) Saponin-permeabilized eosinophils were analyzed by flow cytometry for expression of J1 and J2. Data are presented as percentage of increase in MFI over isotype control. (B) RNA extracted from eosinophils immediately after isolation (Fresh) or after overnight culture in the presence or absence of 100 pM GM-CSF was evaluated by real-time RT-PCR for J1 mRNA expression. Data are presented as the log 10 of the relative quantification, using overnight culture in medium alone as the baseline value. Data are from 1 experiment representative of 3 separate experiments. (C) Total J1 (top panels) or J2 (bottom panels) protein was detected in saponin-permeabilized eosinophils immediately after isolation (Fresh) or after overnight culture in the presence or absence of 100 pM GM-CSF. Shaded histograms = isotype control.