Localization of TGF-α in neutrophil myelocytes from bone marrow. In (a) at lower magnification, a survey of a myelocyte showing a few positive vesicles (arrows). No labeling is shown elsewhere. Nucleus (n). (b) Higher magnification of an area from another myelocyte showing TGF-α labeling in multivesicular bodies (mvb) and multilaminar structures (small arrows). Bars a = 300 nm, b = 200 nm.