Biochemical analysis of initial triggering events of IgE-mediated histamine release from human lung mast cells.
Biochemical analysis of initial triggering events of IgE-mediated histamine release from human lung mast cells.
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IgE 介导的人肺肥大细胞释放组胺的初始触发事件的生化分析。
DOI：
10.4049/jimmunol.130.5.2357
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发表时间：
1983
影响因子：
4.4
通讯作者：
K. Ishizaka
中科院分区：
文献类型：
--
作者：
Teruko Ishizaka;D. Conrad;E. Schulman;A. Sterk;K. Ishizaka
采用逆流离心法分离人肺组织肥大细胞，Percoll梯度浮选分离肥大细胞。纯化的人肥大细胞在抗IgE刺激下释放组胺。人肺肥大细胞释放组胺的最适抗IgE浓度与正常人嗜碱性粒细胞释放组胺所需的浓度相当。人肺肥大细胞可被鼠单抗被动致敏，以诱导组胺释放。抗IgE或其F(ab‘)2片段桥联人肥大细胞上的细胞结合的IgE分子诱导磷脂甲基化和细胞内环磷酸腺苷(CAMP)增加。[~3H]甲基掺入磷脂在抗-IgE攻击后30s达最大值，细胞内cAMP在1min达最大值。这两个值在2到3分钟内都下降到基线水平。这些生化事件之后是钙离子内流和组胺释放。钙摄取和组胺释放分别在2~3min和5~8min达到最大值。吲哚美辛既不能抑制磷脂甲基化，也不能抑制cAMP的初始升高，表明这些生化事件不是前列腺素合成的结果。然而，S-腺苷-L-蛋氨酸介导的甲基化抑制剂3-去氮腺苷和S-异丁酰基3-去氮腺苷对磷脂甲基化的抑制不仅抑制了磷脂甲基化，而且还抑制了cAMP升高和随后的钙摄取和组胺释放。结果表明，人肥大细胞上IgE受体桥联引起的磷脂甲基化是钙离子内流和组胺释放所必需的。
Mast cells were isolated from human lung tissues by counter current centrifugation elutriation, followed by flotation through Percoll gradients. Purified human mast cells released histamine upon challenge with anti-IgE. An optimal concentration of anti-IgE for maximum histamine release from human lung mast cells was comparable to that required for histamine release from normal human basophil granulocytes. Human lung mast cells could be passively sensitized with mouse monoclonal IgE antibody for antigen-induced histamine release. Bridging of cell-bound IgE molecules on human mast cells by anti-IgE or its F(ab')2 fragments induced phospholipid methylation and an increase in intracellular cyclic AMP (cAMP). Incorporation of [3H]methyl groups into phospholipid reached a maximum at 30 sec after challenge with anti-IgE, whereas intracellular cAMP reached a maximum at 1 min. Both values declined to base line levels within 2 to 3 min. These biochemical events were followed by Ca2+ influx and histamine release. Ca2+ uptake and histamine release reached maximum at 2 to 3 min and 5 to 8 min, respectively. Neither phospholipid methylation nor initial rise in cAMP was inhibited by indomethacin, which indicates that these biochemical events are not the result of prostaglandin synthesis. However, inhibition of phospholipid methylation by inhibitors of S-adenosyl-L-methionine-mediated methylation, such as 3-deazaadenosine and S-isobutyryl 3-deazaadenosine, inhibited not only phospholipid methylation but also cAMP rise and subsequent Ca2+ uptake and histamine release. The results indicate that phospholipid methylation induced by bridging of IgE receptors on human mast cells is essential for Ca2+ influx and histamine release.