磷酸酶抑制剂对人嗜碱性粒细胞功能的调节

Regulation of human basophil function by phosphatase inhibitors.

作者信息

Peirce M J, Warner J A, Munday M R, Peachell P T

机构信息

Department of Medicine & Pharmacology, University of Sheffield, Royal Hallamshire Hospital (Floor L).

出版信息

Br J Pharmacol. 1996 Sep;119(2):446-53. doi: 10.1111/j.1476-5381.1996.tb16006.x.

DOI:10.1111/j.1476-5381.1996.tb16006.x

PMID:8886433

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC1915864/

Abstract

Okadaic acid, a cell permeant inhibitor of protein serine/threonine phosphatases (PPs), attenuated the IgE-mediated release of the pre-formed mediator, histamine from human basophils in a time- and dose-dependent manner. Optimal inhibition (77 +/- 4%, P < 0.0001) of histamine release was observed following a 2 h incubation with 1 microM okadaic acid. 2. Okadaic acid and two analogues of okadaic acid were also studied and were found to inhibit the IgE-dependent release of histamine. Concentrations required to inhibit release by 50% (IC50) were 0.6 microM for okadaic acid and 7.5 microM for okadaol, whereas okadaone was inactive. 3. The structurally-unrelated PP inhibitor, calyculin A, also inhibited IgE-dependent histamine release from basophils dose-dependently and was approximately six fold more potent than okadaic acid. 4. The IgE-mediated generation of sulphopeptidoleukotrienes (sLT) from basophils was inhibited by okadaic acid and related analogues with the following rank order of potency; okadaic acid (approx. IC50 0.3 microM) > okadaol (3 microM) > okadaone (inactive). 5. Okadaic acid, okadaol and okadaone (all at 3 microM) inhibited the IgE-mediated generation of the cytokine interleukin 4 (IL4) from human basophils by 67 +/- 9% (P < 0.002), 48 +/- 14% (P < 0.05) and 8 +/- 7% (P = 0.31), respectively. 6. Extracts of purified human basophils liberated 32P from radiolabelled glycogen phosphorylase and this PP activity was inhibited by 17 +/- 3% (P < 0.0005) by a low (2 nM) concentration of okadaic acid and was inhibited by 96 +/- 1% (P < 0.0001) by a higher (5 microM) concentration of okadaic acid. Because a low (2 nM) concentration of okadaic acid inhibits PP2A selectively whereas a higher (5 microM) concentration inhibits both PP1 and PP2A, these findings suggest that both PP1 and PP2A are present in basophils. 7. In total these data suggest that PPs are resident in human basophils and that PPs may be important in the regulation of basophil function.

摘要

冈田酸是一种可透过细胞的蛋白丝氨酸/苏氨酸磷酸酶（PPs）抑制剂，它能以时间和剂量依赖的方式减弱IgE介导的人嗜碱性粒细胞中预先形成的介质组胺的释放。在用1微摩尔冈田酸孵育2小时后，观察到组胺释放的最佳抑制效果（77±4%，P<0.0001）。2. 还研究了冈田酸及其两种类似物，发现它们能抑制IgE依赖的组胺释放。抑制释放50%（IC50）所需的浓度，冈田酸为0.6微摩尔，冈田醇为7.5微摩尔，而冈田酮无活性。3. 结构不相关的PP抑制剂花萼海绵诱癌素A也能剂量依赖性地抑制嗜碱性粒细胞中IgE依赖的组胺释放，其效力比冈田酸高约6倍。4. 冈田酸及相关类似物抑制了嗜碱性粒细胞中IgE介导的硫肽白三烯（sLT）的生成，效力顺序如下：冈田酸（约IC50 0.3微摩尔）>冈田醇（3微摩尔）>冈田酮（无活性）。5. 冈田酸、冈田醇和冈田酮（均为3微摩尔）分别抑制人嗜碱性粒细胞中IgE介导的细胞因子白细胞介素4（IL4）的生成67±9%（P<0.002）、48±14%（P<0.05）和8±7%（P = 0.31）。6. 纯化的人嗜碱性粒细胞提取物从放射性标记的糖原磷酸化酶中释放出32P，低浓度（2纳摩尔）的冈田酸可使这种PP活性受到17±3%的抑制（P<0.0005），高浓度（5微摩尔）的冈田酸可使其受到96±1%的抑制（P<0.0001）。由于低浓度（2纳摩尔）的冈田酸选择性抑制PP2A，而高浓度（5微摩尔）的冈田酸同时抑制PP1和PP2A，这些发现表明PP1和PP2A都存在于嗜碱性粒细胞中。7. 总体而言，这些数据表明PPs存在于人嗜碱性粒细胞中，并且PPs可能在嗜碱性粒细胞功能的调节中起重要作用。