Figure 2. Late endocytic compartments in human T cells

Representative images obtained from resting (A-C) and activated (D-G) T cells exposed to FM1-43 for 1.5 h at 37o C. (B) Enlargement of the boxed area (1) in (A). Note small FM1-43-positive vesicles docked to the perinuclear vacuole. (C) Enlargement of the boxed area (2) in (A). Note that FM1-43-positive endosomes in resting T cells display no internal vesiculation. (E & F) Enlargements of boxed areas (1) and (2) in (D). Note that FM1-43-positive endosomes in activated T cells in (E) have a multivesicular structure. (F) A large multivesicular body (MVB) weakly stained with FM1-43. (G) Early endosomes continue to target large FM1-43-positive MVB. N - nucleus. Scale bars are 0.5 mm.