Phan Tri Giang, Grigorova Irina, Okada Takaharu, Cyster Jason G
Howard Hughes Medical Institute and Department of Microbiology and Immunology, University of California, San Francisco, California 94143, USA.
Nat Immunol. 2007 Sep;8(9):992-1000. doi: 10.1038/ni1494. Epub 2007 Jul 29.
The mechanism of B cell-antigen encounter in lymphoid tissues is incompletely understood. It is also unclear how immune complexes are transported to follicular dendritic cells. Here, using real-time two-photon microscopy we noted rapid delivery of immune complexes through the lymph to macrophages in the lymph node subcapsular sinus. B cells captured immune complexes by a complement receptor-dependent mechanism from macrophage processes that penetrated the follicle and transported the complexes to follicular dendritic cells. Furthermore, cognate B cells captured antigen-containing immune complexes from macrophage processes and migrated to the T zone. Our findings identify macrophages lining the subcapsular sinus as an important site of B cell encounter with immune complexes and show that intrafollicular B cell migration facilitates the transport of immune complexes as well as encounters with cognate antigen.
目前对淋巴组织中B细胞与抗原相遇的机制尚不完全清楚。免疫复合物如何转运至滤泡树突状细胞也不清楚。在此，我们利用实时双光子显微镜观察到免疫复合物通过淋巴液迅速传递至淋巴结被膜下窦的巨噬细胞。B细胞通过补体受体依赖性机制从穿透滤泡的巨噬细胞突起捕获免疫复合物，并将其转运至滤泡树突状细胞。此外，同源B细胞从巨噬细胞突起捕获含抗原的免疫复合物并迁移至T细胞区。我们的研究结果表明，被膜下窦内衬的巨噬细胞是B细胞与免疫复合物相遇的重要部位，并表明滤泡内B细胞迁移有助于免疫复合物的转运以及与同源抗原的相遇。
