Imaging B-cell receptor signaling by single-molecule techniques.
Imaging B-cell receptor signaling by single-molecule techniques.
复制标题
通过单分子技术对 B 细胞受体信号传导进行成像。
作者：
P. Tolar;T. Meckel
B细胞的激活启动了对病原体的抗体反应。最近对活体B细胞的成像显示，B细胞在淋巴组织中快速移动，寻找捕获在抗原呈递细胞表面的抗原。B细胞抗原受体(BCR)对抗原的识别导致BCR的微集聚，并启动细胞内信号，促使B细胞停止并与抗原提呈细胞形成免疫突触。尽管调节这些事件的BCR下游的生化信号通路正在变得更具特征性，但BCR微簇和激活的最初分子步骤仍然难以捉摸。在一定程度上，这是因为细胞-细胞接触的动态使观察抗原诱导的BCR变化在技术上具有挑战性。在这里，我们回顾了单分子成像技术，这些技术有助于提供有关BCR小群体分子行为的新信息，因为它们在动态运动的B细胞中启动细胞内信号传递。这些技术一般适用于细胞间接触所涉及的广泛的膜受体的研究。
B-cell activation initiates antibody responses against pathogens. Recent imaging of B cells in vivo shows that B cells move rapidly through lymphoid tissues to search for antigens captured on the surfaces of antigen-presenting cells. Recognition of antigens by the B-cell antigen receptor (BCR) leads to microclustering of the BCR and the initiation of intracellular signaling that prompts the B cells to stop and form immunological synapses with the antigen-presenting cells. Although the biochemical signaling pathways downstream of the BCR that mediate these events are becoming better characterized, the initial molecular steps in BCR microclustering and activation remain elusive. In part, this is because the dynamics of the cell-cell contact makes the observation of the antigen-induced changes in the BCR technically challenging. Here we review single-molecule imaging techniques that help to provide new information on the molecular behavior of small populations of the BCR as they initiate intracellular signaling in a dynamically moving B cell. The techniques are generally applicable to the study of a broad range of membrane receptors involved in cell-cell contacts.