Department of Respiratory Diseases and Allergy, Aarhus University Hospital, Denmark.
Department of Engineering, Aarhus University, Denmark.
Immunol Lett. 2019 Jun;210:40-46. doi: 10.1016/j.imlet.2019.04.003. Epub 2019 Apr 17.
IgE-mediated activation of basophil granulocytes and mast cells follows a bell-shaped dose-response curve. The decreased activation at supraoptimal allergen stimulation is thought to be associated with SH2-containing inositol-5'-phosphatase 1 (SHIP-1). SHIP-1 phosphorylation is inversely related to IgE-mediated releasability of basophils. This study sought to clarify the regulatory role of SHIP-1 in degranulation of basophil granulocytes and mast cells by selective inhibition of the phosphatase function of SHIP-1with 3-α-aminocholestane (3-α-AC). Six grass pollen allergic patients, six non-responder patients and six cultured human primary mast cell lines were included. The effect of 3-α-AC (1-60 μM, 30 min, 37 °C) was analyzed at individual suboptimal, optimal and supra-optimal allergen concentrations. The activity, upregulation of CD63, measured at different conditions was compared to evaluate the maximal effect of selective SHIP-1 inhibition. Basophils of five non-responder patients were treated with 3-α-AC (10 μM, 30 min, 37 °C). At high concentrations (>60 μM) of 3-α-AC, cells appeared to enter apoptosis. The median reactivity increased from 27.1% to 44.9% CD63 basophils at 10 μM of 3-α-AC and suboptimal allergen stimulation (p = 0.0153). There was no effect on blood basophils of 3-α-AC at optimal or supra-optimal allergen concentrations. In contrast, treatment with more than 6 μM 3-α-AC significantly inhibited mast cell reactivity. 10 μM 3-α-AC reduced median reactivity from 32.85% to 16.5% CD63+ mast cells (p = 0.0465). Treatment with 3-α-AC did not increase response of basophils of non-responder patients. Modulating blood basophils with 3-α-AC enhanced reactivity only at suboptimal allergen concentration, and basophils from non-responders did not regain responsiveness to IgE stimulation. 3-α-AC inhibited the IgE response of mast cells in a dose dependent manner.
免疫球蛋白 E 介导的嗜碱性粒细胞和肥大细胞的激活遵循钟形剂量反应曲线。在超最佳过敏原刺激下，活性降低被认为与含 SH2 的肌醇 5'-磷酸酶 1（SHIP-1）有关。SHIP-1 的磷酸化与 IgE 介导的嗜碱性粒细胞释放能力呈负相关。本研究旨在通过选择性抑制 SHIP-1 的磷酸酶功能，用 3-α-氨基胆甾烷（3-α-AC）来阐明 SHIP-1 在嗜碱性粒细胞和肥大细胞脱颗粒中的调节作用。纳入了 6 名花粉过敏患者、6 名无反应患者和 6 个人源原代肥大细胞系。在个体亚最佳、最佳和超最佳过敏原浓度下分析 3-α-AC（1-60μM，30min，37°C）的作用。比较不同条件下 CD63 的上调和活性，以评估选择性 SHIP-1 抑制的最大效果。用 3-α-AC（10μM，30min，37°C）处理 5 名无反应患者的嗜碱性粒细胞。在 3-α-AC 的高浓度（>60μM）下，细胞似乎进入了凋亡。在 10μM 3-α-AC 和亚最佳过敏原刺激下，CD63 嗜碱性粒细胞的中位数反应性从 27.1%增加到 44.9%（p=0.0153）。在最佳或超最佳过敏原浓度下，3-α-AC 对血液嗜碱性粒细胞没有影响。相比之下，用 6μM 以上的 3-α-AC 处理显著抑制了肥大细胞的反应性。用 10μM 3-α-AC 可使 CD63+肥大细胞的中位数反应性从 32.85%降低至 16.5%（p=0.0465）。用 3-α-AC 处理不能增加无反应患者嗜碱性粒细胞的反应性。用 3-α-AC 调节血液嗜碱性粒细胞仅在亚最佳过敏原浓度下增强反应性，而无反应者的嗜碱性粒细胞不能重新获得对 IgE 刺激的反应性。3-α-AC 以剂量依赖的方式抑制肥大细胞的 IgE 反应。
