Effect of antitubulins on spontaneous and chemotactic migration of neutrophils under agarose.

The effect of colchicine, Nocodazole or vinblastine on the movement of mouse bone marrow neutrophils was examined by the method of migration under agarose. Migration was estimated by counts of the numbers of cells that left the wells and moved under the gel. Micromolar concentrations of the agents increased spontaneous migration 2- to 4-fold, while lumicolchicine was ineffective. The increase may be due to the disassembly of the microtubular skeleton, making the cells more fluid, or to some other effect of the drugs. Since other agents, such as serum, low osmolality and low pH also enhance migration, these were tried in combination with a pretreatment of the cells with colchicine. Serum and colchicine acted synergistically, low osmolality and colchicine were additive. Possible, the enhancement of neutrophil migration by serum or lowered osmolality does not require intact microtubules. At low pH, colchicine had very little stimulatory effect, perhaps indicating that the microtubules are more colchicine-resistant at low pH. Although antibular drugs showed such marked effects on spontaneous migration, the chemotactic attraction of the neutrophils towards activated serum was unaffected. This indicates that the sensory and control mechanisms of the cells are resistant to antibulins.