Volume 6 issue 12 November 2005
Human eosinophils secrete preformed, granule-stored interleukin-4 (IL-4) through distinct vesicular compartments
Rossana C. N. Melo, Lisa A. Spencer, Sandra A. C. Perez , Ionita Ghiran Ann M. Dvorak and Peter F. Weller

Movie 1: Tomography of an emptying eosinophil granule exhibiting structural changes associated with the formation of eosinophil sombrero vesicles (EoSVs). Eosinophils were isolated from healthy donors and stimulated with 100 ng/mL eotaxin for 1 h at 37 ºC, chemically fixed and embedded in Eponate. Thick sections (400 nm) were cut and analyzed by automated EM tomography (dual-axis, tilting from -65 ° to + 65° at 1° intervals, magnification of 40,000x). The tomogram corresponds to Figure 4.

Movie 1 (.mov)

Movie 2: Three-dimensional (3D) model of an emptying eosinophil granule and proximate eosinophil sombrero vesicles (EoSVs). The granule peripheral delimiting membrane was traced in blue and the membranes of emerging vesicles (visualized as progressive tubular extensions at the granule surface) in yellow, green and red. Some intragranular subcompartments were outlined in green. Note also the spatial organization of proximate EoSVs (traced in pink), imaged as large, curved tubular structures surrounding a cytoplasmic center. The 3D model was generated from ~ 4 nm thick serial slices (shown in Movie 1) obtained by automated electron tomography from an eotaxin-stimulated eosinophil. The 3D model corresponds to Figure 4.

Movie 2 (.mov)