In human lung adenocarcinoma cells exposed to vinblastine (VLB) and st
ained with fast green, large tubulin crystals were seen in the cytopla
sm. In contrast, cells exposed to taxol had prominent bundles of stabi
lized microtubules. Pre- or co- incubation of cells with taxol before
exposure to VLB prevented formation of the crystals. However, VLB did
not prevent formation of stabilized microtubules by taxol if added at
the same time. Under a fluorescent microscope, VLB induced crystals st
ained with secondary antibodies against anti-alpha- and anti-beta- tub
ulin antibodies. Neither of the drugs altered binding of the antibodie
s to these crystals.