Santoro P, Cacciapuoti C, Palumbo A, Graziano D, Annunziata S, Capasso L, Formisano S, Ciccimarra F
Department of Pediatrics, Università degli Studi di Napoli Federico II, Italy.
Ital J Biochem. 1998 Mar;47(1):13-8.
Modulation of neutrophil response to naturally occurring stimuli is important to avoid host tissue injure. Both soluble and particulate stimuli may induce superoxide anion generation in human polymorphonuclear leukocytes. Recently wortannin has been shown to inhibit the N-formyl-methionyl-leucyl-phenylalanine (fMLP) induced activation of respiratory burst via phosphatidylinositol 3-kinase. However no data are available about the effect of the inhibitor on the respiratory burst induced by a particulate stimulus. In this paper we studied the effect of wortmannin on E. coli induced respiratory burst and phagocytosis by flow cytometry, which allows the quantitation of both H2O2 production and ingested bacteria in whole blood samples without the need of purification and concomitant manipulation of the cells. The effects of worthmannin on fMLP-induced chemotaxis was also examined by the under agarose method. Neither the E. coli nor the fMLP-induced responses were blocked by wortmannin, suggesting that PI 3-kinase activity is not required to activate these neutrophil functions. Since it is known that the respiratory burst elicited by fMLP is blocked by wortmannin, our results suggest that the generation of oxygen radicals is controlled via different signal transduction pathways, depending on the agonist used.
调节中性粒细胞对自然刺激的反应对于避免宿主组织损伤很重要。可溶性和颗粒性刺激均可诱导人多形核白细胞产生超氧阴离子。最近发现渥曼青霉素可通过磷脂酰肌醇3激酶抑制N-甲酰甲硫氨酰-亮氨酰-苯丙氨酸（fMLP）诱导的呼吸爆发激活。然而，关于该抑制剂对颗粒性刺激诱导的呼吸爆发的影响尚无数据。在本文中，我们通过流式细胞术研究了渥曼青霉素对大肠杆菌诱导的呼吸爆发和吞噬作用的影响，该方法可对全血样本中的H2O2产生和摄入细菌进行定量，而无需对细胞进行纯化和同步操作。还通过琼脂糖下法检测了渥曼青霉素对fMLP诱导的趋化作用的影响。渥曼青霉素未阻断大肠杆菌或fMLP诱导的反应，表明激活这些中性粒细胞功能不需要PI 3激酶活性。由于已知fMLP引发的呼吸爆发会被渥曼青霉素阻断，我们的结果表明，取决于所使用的激动剂，氧自由基的产生是通过不同的信号转导途径控制的。
