Neutrophils exhibit rapid cell spreading and phagocytosis, both requiring a large apparent increase in the cell surface area. The wrinkled surface topography of these cells may provide the membrane reservoir for this. Here, the effects of manipulation of the neutrophil cell surface topography on phagocytosis and cell spreading were established. Chemical expansion of the plasma membrane or osmotic swelling had no effects. However, osmotic shrinking of neutrophils inhibited both cell spreading and phagocytosis. Triggering a Ca²⁺ signal in osmotically shrunk cells (by IP₃ uncaging) evoked tubular blebs instead of full cell spreading. Phagocytosis was halted at the phagocytic cup stage by osmotic shrinking induced after the phagocytic Ca²⁺ signalling. Restoration of isotonicity was able to restore complete phagocytosis. These data thus provide evidence that the wrinkled neutrophil surface topography provides the membrane reservoir to increase the available cell surface area for phagocytosis and spreading by neutrophils.

中性粒细胞表现出快速的细胞扩散和吞噬作用，两者都需要细胞表面积的明显增加。这些细胞的皱纹表面形貌可为此提供膜储存器。在这里，建立了嗜中性粒细胞表面形貌的操纵对吞噬作用和细胞扩散的影响。质膜的化学膨胀或渗透溶胀没有影响。然而，嗜中性粒细胞的渗透性收缩抑制细胞扩散和吞噬作用。在渗透性收缩的细胞中触发Ca ²⁺信号（通过IP ₃解封）引起管状小泡，而不是整个细胞扩散。吞噬Ca ²⁺引起的渗透性收缩使吞噬作用在吞噬杯阶段停止发信号。等渗性的恢复能够恢复完全的吞噬作用。因此，这些数据提供了证据，即中性粒细胞起皱的表面形貌提供了膜贮存器，以增加可利用的细胞表面积用于中性粒细胞的吞噬和扩散。