Xu X, Håkansson L
Department of Medical Sciences, Clinical Chemistry, University Hospital, Uppsala, Sweden.
Clin Exp Allergy. 2000 Jun;30(6):794-806. doi: 10.1046/j.1365-2222.2000.00779.x.
Varying release of eosinophil granule proteins depending on the stimulus and environmental factors has previously been reported.
To investigate the degranulation from adherent eosinophils by using mixed granulocytes.
Granulocytes isolated by Percoll gradient centrifugation were incubated on plates coated with plasma and tissue fibronectin, fibrinogen or human serum albumin (HSA) and stimulated with Mn2+, phorbol-myristate-acetate (PMA), formyl-methionyl-leucyl-phenylalanine (f-MLP) and combinations thereof, respectively. The release of eosinophil cationic protein (ECP) was measured by radioimmunoassay.
Unstimulated eosinophils incubated in wells coated with plasma and tissue fibronectin, fibrinogen or HSA did not release any ECP. Furthermore, Mn2+ (5 mmol/L) did not induce release of ECP despite the fact that adhesion of eosinophils to these four proteins was induced. PMA stimulated a dose-dependent release of ECP. Contemporaneous stimulation of eosinophils with PMA and Mn2+ induced a dramatically increased release of ECP regardless of which protein the eosinophils were adhering to. A small but significant release of ECP was found when eosinophils incubated on plates coated with fibrinogen and HSA were stimulated by f-MLP. Contemporaneous stimulation of eosinophils with f-MLP and Mn2+ did not induce any synergistic effect on the release of ECP. On the contrary, Mn2+ inhibited the release of ECP induced by f-MLP from eosinophils. Serum-opsonized Sephadex particles stimulated a potent increase of the release of ECP up to 12%-14% in the presence of plasma fibronectin and, in particular, fibrinogen. The kinetics of eosinophil adhesion and degranulation showed that the cellular adhesion preceded the degranulation response and that the degranulation patterns depend on the stimuli and environment.
The present study indicated that cellular adhesion plays an important role in the regulation of eosinophil degranulation, but that adhesion and degranulation can be induced separately.
先前已有报道，嗜酸性粒细胞颗粒蛋白的释放会因刺激因素和环境因素的不同而有所差异。
通过使用混合粒细胞来研究黏附嗜酸性粒细胞的脱颗粒情况。
通过Percoll梯度离心分离出的粒细胞，分别在包被有血浆和组织纤连蛋白、纤维蛋白原或人血清白蛋白（HSA）的平板上孵育，并用Mn2 +、佛波酯-肉豆蔻酸酯-乙酸酯（PMA）、甲酰甲硫氨酰亮氨酰苯丙氨酸（f-MLP）及其组合进行刺激。采用放射免疫分析法测定嗜酸性粒细胞阳离子蛋白（ECP）的释放量。
在包被有血浆和组织纤连蛋白、纤维蛋白原或HSA的孔中孵育的未受刺激的嗜酸性粒细胞未释放任何ECP。此外，尽管Mn2 +（5 mmol/L）可诱导嗜酸性粒细胞黏附于这四种蛋白，但并未诱导ECP的释放。PMA刺激ECP呈剂量依赖性释放。PMA和Mn2 +同时刺激嗜酸性粒细胞，无论嗜酸性粒细胞黏附于哪种蛋白，均会显著增加ECP的释放。当在包被有纤维蛋白原和HSA的平板上孵育的嗜酸性粒细胞受到f-MLP刺激时，发现有少量但显著的ECP释放。f-MLP和Mn2 +同时刺激嗜酸性粒细胞，对ECP的释放未产生任何协同作用。相反，Mn2 +抑制f-MLP诱导的嗜酸性粒细胞ECP释放。在血浆纤连蛋白尤其是纤维蛋白原存在的情况下，血清调理的葡聚糖颗粒可有效促进ECP释放增加至12% - 14%。嗜酸性粒细胞黏附和脱颗粒的动力学表明，细胞黏附先于脱颗粒反应，且脱颗粒模式取决于刺激因素和环境。
本研究表明，细胞黏附在嗜酸性粒细胞脱颗粒的调节中起重要作用，但黏附和脱颗粒可分别被诱导。
