HS 1 is not required for eosinophil GATA1 expression and eosinophil maturation. (A) Morphology of eosinophils purified from blood and spleen of IL-5 transgenic mice with an intact (WT) or deleted HS1 enhancer (ΔneoΔHS). After cytospin, cells were stained with MGG stain to check their morphology or with Fast Green and Neutral Red to document presence of cytoplasmic green eosinophilic granules. Original magnification, × 400. (B) GATA1 mRNA levels were determined by Real-Time Taqman PCR in purified blood eosinophils from IL-5 transgenic mice with an intact (WT) or deleted HS1 (ΔneoΔHS) enhancer. The results are from 4 mice in each group. Error bars represent ± 1 SD.