Sensory adaptation of leukocytes to chemotactic peptides
Sensory adaptation of leukocytes to chemotactic peptides
复制标题
白细胞对趋化肽的感觉适应
作者：
S. Zigmond;S. Sullivan
在趋化因子 N-甲酰正亮氨酰基苯丙氨酸 (f-NorleuLeuPhe) 浓度快速变化后，研究了多形核白细胞 (PMN) 的形态和行为 (Schiffmann 等，1975，Proc. Natl. Acad. Sci. U. S. A. 72:1059--1062)。肽浓度增加后，细胞变圆，在其大部分表面形成片状伪足或褶边，并停止运动。这些变化是暂时的。延迟一段时间后，仍然存在肽的细胞会撤回大部分褶边并恢复运动，仅在其前面形成褶边。当肽浓度进一步增加时，细胞会重复短暂的普遍褶皱。行为变化发生在与可饱和受体结合相同的剂量范围内。浓度增加后瞬时响应的持续时间大致与由于浓度变化而占据的细胞受体数量的增加成正比。降低肽的浓度会导致细胞在重新开始运动之前短暂变圆并形成气泡。细胞对趋化因子的反应性的这些方面的瞬时性质似乎是由于细胞的适应。适应趋化因子浓度的能力对于白细胞趋化性可能很重要。
The morphology and behavior of polymorphonuclear leukocytes (PMNs) were studied after rapid changes in the concentration of a chemotactic factor N-formylnorleucylleucylphenylalanine (f-NorleuLeuPhe) (Schiffmann et al., 1975, Proc. Natl. Acad. Sci. U. S. A. 72:1059-- 1062). After an increase in peptide concentration, the cells round, form lamellipodia or ruffles over most of their surface, and stop locomotion. These changes are transient. After a delay, the cells, still in the presence of peptide, withdraw most of the ruffles and resume locomotion, forming ruffles only at their front. Cells repeat the transient generalized ruffling upon further increase in peptide concentration. The behavioral changes occur over the same dose range as binding to a saturable receptor. The duration of the transient response after a concentration increase is roughly proportional to the increase in the number of cell receptors occupied as a result of the concentration change. Decreasing the concentration of peptide causes the cells to round transiently and form blebs before they recommence locomotion. The transient nature of these aspects of the cell's responsiveness to chemotactic factors appears to be due to adaptation by the cells. The ability to adapt to the concentration of a chemotactic factor may be important in leukocyte chemotaxis.