Figure 5.

Cationic ferritin and DAMP colocalization in cultured chromaffin cells

A, non-stimulated cells. Cationic ferritin, used as a tracer for endosomes, has a stippled, electron-dense appearance and is labelled with 10 nm diameter immunogold particles. DAMP, used to indicated acidic organelles, is immunolabelled with 5 nm immunogold particles. The plasma membrane (arrowheads) and examples of cationic ferritin-labelled endosomal structures (larger arrows and inset) are indicated. DAMP-containing active dense-core vesicles (small arrows) do not display cationic ferritin. B, in stimulated chromaffin cells, cationic ferritin also does not appear in active dense-cored vesicles (arrows as in A). Scale bar: 200 nm.