NMMHC-IIA localization in megakaryocytes derived from peripheral blood CD34⁺ cells. (A) Megakaryocytes derived from peripheral blood CD34⁺ cells of healthy controls and patients were double-stained with anti-GPIIb mouse monoclonal antibody SZ22 (green) and PRB440P (red, top panels) or with anti-GPIIb rabbit polyclonal antibody (green) and NT629 (red, bottom panels). PRB440P diffusely stained cytoplasm of megakaryocytes from control and patients, whereas NT629 coarsely and heterogeneously stained those of patients. (B) Megakaryocytes that produce platelets. Original magnification, ×1000. (C) Flow cytometric analysis of plateletlike particles double stained with anti-GPIbα and anti-GPIIIa antibodies. Geometric mean of forward scatter of GPIbα and GPIIIa double-positive cells was shown in inset.