Flow cytometric analysis of intracytoplasmic MBP in MCs and eosinophils.

Representative results obtained with permeabilized CB-derived MCs (A) and eosinophils (B) are shown. The histograms indicated as shaded areas with bold lines were obtained using the anti-MBP MoAb (BMK-13), whereas those indicated as open areas with thin lines were obtained using control antibody. The experiments using another anti-MBP MoAb (AHE-2) derived from a different hybridoma gave similar histograms. The mean fluorescence intensity ratios of MBP to control in PB- and CB-derived MCs and eosinophils were, respectively, 14.3 ± 2.1 (n = 10) and 2.4 ± 0.5 (n = 3). The levels of coefficient of variation for MCs and eosinophils were, respectively, 86.2% ± 6.4% and 37.4% ± 5.3% (n = 10 and n = 3), indicating that the intensities of MBP fluorescence in MCs varied widely compared with those in eosinophils.