Figure 4.

Reversing the induced growth of membrane nanotubes by the addition of anti-cholera toxin B (CTB). The addition of CTB to RT4 A) and T24 B) cells reveals the growth of membrane nanotubes (arrows), as well as membrane lipid rafts (marked by fluorescent CTB–GM1 complexes) at the tips and entire length of membrane nanotubes. Note that some membrane nanotubes (ICNs) make contact with a neighboring T24 cell (b; arrowheads), and the presence of a microvesicular structure at the tip of membrane nanotubes (close up view). The addition of anti-CTB causes the retraction of membrane nanotubes in both RT4 C) and T24 D) cells.