Fig. 2.

Transmission electron microscopic images of crocidolite fibers engulfed by MeT5A cells. MeT5A cells at 70% confluence were incubated with 20 µg/cm² crocidolite for 2 h. (A, B, C and D) Crocidolite fibers were engulfed by MeT5A cells from the cell surface with abundant microvilli. (E and F) Crocidolite fibers inside the cytoplasm were found within membrane-bound vesicles. Solitary fibers (C and E) and fiber bundles (shown in cross section) (D and F) appeared to have no difference in the way of entering cells. Crocidolite fibers tended to form bundles, and counting the exact number of fibers included in each bundle was difficult (A, B, D and F).