Ultrastructural immunonanogold localization of syntaxin 2 in unstimulated human platelets.

(A) α-Granule (arrowhead), OCS (open arrows), and plasma membranes (solid arrows) are labeled. Another OCS membrane (B), several α-granule membranes (C), and plasma membrane (D) labeled with silver-enhanced gold particles are shown. (E) Specific primary antibody was replaced by an irrelevant goat IgG. No gold particles are present. Original magnifications: A, × 86 000; B, × 77 000; C, × 70 000; D, × 83 000; E, × 42 000.