Follicular dendritic cells: beyond the necessity of T-cell help
Follicular dendritic cells: beyond the necessity of T-cell help
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DOI：
10.1016/s1471-4906(01)01942-1
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发表时间：
2001-07-01
影响因子：
16.8
通讯作者：
Qin, DH
中科院分区：
文献类型：
--
作者：
Tew, JG;Wu, JH;Qin, DH
滤泡树突状细胞（FDC）是B细胞的有效辅助细胞，但其活性的分子基础尚不清楚。通过阻断FDC和/或B细胞上的配体和受体来指示参与FDC-B-细胞相互作用的几种重要分子。FDC上补体衍生的CD 21配体与B细胞辅助受体复合物中的CD 21的结合传递了一个关键信号，该信号显著增强了抗原与B细胞受体（BCR）结合所传递的刺激。固定在FDC上的抗原-抗体复合物中的IG可结晶片段（Fc）与Fc γ受体IIB（Fc γ RIIB）的结合降低了基于免疫受体酪氨酸的抑制基序（ITIM）的活化，这是由BCR和Fc γ RIIB的交联介导的。因此，FDC使负B细胞信号最小化。简而言之，这些配体-受体相互作用有助于向B细胞发出信号，并满足B细胞刺激的需要，这超出了T细胞帮助的必要性。
Follicular dendritic cells (FDCs) are potent accessory cells for B cells, but the molecular basis of their activity is not understood. Several important molecules involved in FDC-B-cell interactions are indicated by blocking the ligands and receptors on FDCs and/or B cells. The engagement of CD21 in the B-cell coreceptor complex by complement-derived CD21 ligand on FDCs delivers a crucial signal that dramatically augments the stimulation delivered by the binding of antigen to the B-cell receptor (BCR). The engagement of Fc gamma receptor IIB (Fc gamma RIIB) by the Ig crystallizable fragment (Fc) in antigen-antibody complexes held on FDCs decreases the activation of immunoreceptor tyrosine-based inhibition motifs (ITIMs), mediated by the crosslinking of BCR and Fc gamma RIIB. Thus, FDCs minimize a negative B-cell signal. In short, these ligand-receptor interactions help to signal to B cells and meet a requirement for B-cell stimulation that goes beyond the necessity of T-cell help.