Richter J, Andersson T, Olsson I
Department of Medicine, Lund Hospital, Sweden.
J Immunol. 1989 May 1;142(9):3199-205.
Both TNF and and granulocyte/macrophage CSF (GM-CSF) can activate neutrophils. The aim of this work was to determine the effect of these cytokines on neutrophil degranulation. The secretion of lactoferrin of secondary granules and myeloperoxidase (MPO) of primary granules from single adherent human neutrophils was assayed by use of a reverse hemolytic plaque assay. Both rTNF and rGM-CSF caused secretion of lactoferrin in a dose-dependent manner. Both agents also caused secretion of MPO, but only in the presence of cytochalasin B. Preincubation with pertussis toxin inhibited rGM-CSF-induced secretion of both lactoferrin and MPO. rTNF-induced MPO secretion was also blocked by pertussis toxin, whereas lactoferrin secretion was only slightly affected. Neither rTNF nor rGM-CSF caused any detectable changes in the concentration of cytoplasmic free Ca2+ in fura-2-loaded cells. However, when neutrophils were loaded with increasing concentrations of quin-2 to buffer any local, not detectable, changes in the concentration of cytoplasmic Ca2+, both rTNF- and rGM-CSF-induced secretion of lactoferrin and MPO were almost totally abolished at a relatively low quin-2 concentration. These results suggest a role of a regulatory G-protein and minute local changes in the concentration of cytoplasmic Ca2+ in TNF- and GM-CSF-induced neutrophil degranulation.
肿瘤坏死因子（TNF）和粒细胞/巨噬细胞集落刺激因子（GM-CSF）均可激活中性粒细胞。本研究的目的是确定这些细胞因子对中性粒细胞脱颗粒的影响。通过反向溶血空斑试验检测单个贴壁人中性粒细胞次级颗粒乳铁蛋白和初级颗粒髓过氧化物酶（MPO）的分泌。重组TNF（rTNF）和重组GM-CSF（rGM-CSF）均以剂量依赖方式引起乳铁蛋白分泌。两种因子也都引起MPO分泌，但仅在细胞松弛素B存在的情况下。用百日咳毒素预孵育可抑制rGM-CSF诱导的乳铁蛋白和MPO分泌。百日咳毒素也可阻断rTNF诱导的MPO分泌，而乳铁蛋白分泌仅受到轻微影响。rTNF和rGM-CSF均未引起fura-2负载细胞中细胞质游离Ca2+浓度的任何可检测变化。然而，当中性粒细胞用浓度递增的quin-2负载以缓冲细胞质Ca2+浓度中任何局部的、不可检测的变化时，在相对较低的quin-2浓度下，rTNF和rGM-CSF诱导的乳铁蛋白和MPO分泌几乎完全被消除。这些结果表明调节性G蛋白和细胞质Ca2+浓度的微小局部变化在TNF和GM-CSF诱导的中性粒细胞脱颗粒中起作用。
