Scanning electron microscopy study of neutrophil membrane tubulovesicular extensions (cytonemes) and their role in anchoring, aggregation and phagocytosis. The effect of nitric oxide

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

“…9 Nitric oxide (NO), the physiological regulator of leukocyte adhesion to endothelium, appears to be a natural causative factor for TVE formation. 10,11 NO-induced neutrophil tubulovesicular extensions connected neutrophils to substrata and to the other cells, and bound and aggregated pathogenic bacteria over a distance of several cell diameters.…”

Novel membrane cell projection defects in Wiskott-Aldrich syndrome B cells

“…However, tenupodia correspond to those previously described as 'retraction fibers' (30,31). Cytonemes have already been described in neutrophils (29,32) and also in B lymphocytes (33). These B cell cytonemes, rich in lipid rafts and actin filaments, are proposed to play a role in long-range communication and/or transportation of signaling molecules during the immune response (33).…”

Membrane tubulovesicular extensions (cytonemes)

“…These data demonstrated that TVEs attach cells to the substrata in a selectin-dependent, but β2-and β1-integrin-independent, manner. 8,26 TVEs with unattached tips were flexible and had a tendency to shed from the cells. The extensions interconnecting neutrophils were either flexible or straight.…”

“…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.…”