The increase in intracellular free calcium associated with IgG gamma 2b/gamma 1 Fc receptor-ligand interactions: role in phagocytosis.
The increase in intracellular free calcium associated with IgG gamma 2b/gamma 1 Fc receptor-ligand interactions: role in phagocytosis.
复制标题
与 IgG gamma 2b/gamma 1 Fc 受体-配体相互作用相关的细胞内游离钙的增加：在吞噬作用中的作用。
DOI：
10.1073/pnas.81.17.5430
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发表时间：
1984
影响因子：
11.1
通讯作者：
Cohn,ZA
中科院分区：
文献类型：
--
作者：
Young,JD;Ko,SS;Cohn,ZA
通过使用荧光指示剂quin-2在J774小鼠巨噬细胞中测量细胞溶质游离钙的浓度[Ca 2 +]i。静息[Ca 2 +]i为87 nM。免疫球蛋白γ 2b/γ 1 Fc受体的一些特定配体的添加导致[Ca 2 +]i的瞬时增加，其幅度取决于受体聚集的程度。单价配体只给出了一个小的Ca 2+信号，但阻断了细胞对随后加入的多价配体的反应。用抗体包被的红细胞孵育将巨噬细胞[Ca 2 +]i提高到微摩尔水平。[Ca2+]i的变化仅部分抑制了外部Ca 2+的情况下，这表明除了外部Ca 2+的流入，从内部存储的Ca 2+的释放。这些内部储存并不局限于线粒体。[Ca ~（2+）]i的最佳范围是吞噬作用所必需的。用quin-2缓冲[Ca 2 +]i并在没有外部Ca 2+的情况下用奎宁处理细胞导致吞噬作用的抑制。用钙离子载体A23187将[Ca 2 +]i增加到微摩尔水平也导致类似的抑制作用。我们建议参与本地化的胞质Ca 2+梯度产生必要的吞噬信号。
The concentration of cytosolic free calcium, [Ca2+]i, was measured in J774 mouse macrophages by use of the fluorescent indicator quin-2. Resting [Ca2+]i was 87 nM. Addition of a number of specific ligands to the immunoglobulin gamma 2b/gamma 1 Fc receptor resulted in a transient increase in [Ca2+]i, the magnitude of which depended on the extent of receptor aggregation. Monovalent ligands gave only a small Ca2+ signal but blocked cell response to subsequent addition of multivalent ligands. Incubation with antibody-coated erythrocytes raised macrophage [Ca2+]i to micromolar levels. [Ca2+]i changes were only partially inhibited by the absence of external Ca2+, suggesting the release of Ca2+ from internal stores in addition to an influx of external Ca2+. These internal stores were not limited to mitochondria. An optimal range of [Ca2+]i was required for phagocytosis. Buffering [Ca2+]i with quin-2 and treating cells with quinine in the absence of external Ca2+ resulted in inhibition of phagocytosis. Increasing [Ca2+]i to micromolar levels with the calcium ionophore A23187 also resulted in similar inhibitory effects. We suggest the involvement of localized cytosolic Ca2+ gradients in generating the signals necessary for phagocytosis.