Microbial alkaloid staurosporine induces formation of nanometer-wide membrane tubular extensions (cytonemes, membrane tethers) in human neutrophils

Membrane tubulovesicular extensions (cytonemes)

“…2). 8,28 These data indicate that the development of TVEs occurs independently of the cytoskeleton, i.e., neutrophil TVEs are not F-actin-or microtubule-driven protrusions.…”

“…Extracellular binding of bacteria by neutrophil TVEs represents an alternative phagocytotic mechanism to bind and kill pathogens. [26][27][28][29] Notably, there are principle differences between TVEs and so-called "neutrophil extracellular traps," or NETs. According to Zychlinsky and colleagues, neutrophils exposed to uncoated coverslips in the presence of phorbol ether for 4-6 h "extrude" chromatin and granule proteins that form NETs for binding and killing pathogens.…”

“…These carriers fuse with the neutrophil plasma membrane upon diameter varied in the range of 160-240 nm, depending on the conditions. 8,27,28 TVEs can obtain lengths of greater than 80 nm in 20 min. Fluorescent microscopy using cytoplasmic and lipid dyes demonstrated that TVEs are covered with membrane and contain neutrophil cytoplasm.…”

“…Fluorescent microscopy using cytoplasmic and lipid dyes demonstrated that TVEs are covered with membrane and contain neutrophil cytoplasm. 27,28 In neutrophils, TVEs grow unhindered in the presence of the microtubule-destabilizing agent colchicine or in the presence of agents that disrupt the actin cytoskeleton, such as cytochalasin B or D (Fig. 2).…”

“…8,27,28,36 Similar to malignant cells, leukocytes possess a high rate of glycolysis, even in the presence of oxygen. 37 The extrusion of TVEs from the cells occurred upon neutrophil adhesion to the fibronectin-coated substrata in the presence of iodoacetic acid, an inhibitor of the glycolytic enzyme glyceraldehyde-3-phosphate dehydrogenase (GAPDH) or phloretin, an inhibitor of facilitative glucose transporters.…”