TISSUE IMAGING IN CELL BIOLOGY

继续开发三种成像和培养技术- 维度多细胞系统，我们已经培育出活体人类和 低剪切力旋转壁血管中的小鼠淋巴组织 生物反应器(RWV)。淋巴组织的碎片在RWV中仍然活着 至少两个星期。组织中的细胞迁移到 周围的媒体。细胞在组织外的迁移是可逆的： 来自外围介质的标记细胞重新填充组织和它们的 命运可以通过共聚焦显微镜成像来追踪。迁移 通过将组织碎片嵌入体内可以部分阻止细胞 胶原蛋白凝胶。当组织被破坏时细胞迁移完全停止 包埋在琼脂糖凝胶中。琼脂糖包埋的组织块仍然存在 活着：它们消耗氧气和葡萄糖，向介质中产生免疫球蛋白G， 保留了其架构的基本元素，包括富含B细胞 生发中心被T细胞包围。高密度类似于 凝胶顶部培养的组织块(组织培养)。 琼脂糖包埋组织块的共聚焦成像揭示了一个网络 生发中心的滤泡-树突状细胞。琼脂糖包埋 组织块保留更多的细胞和更少的凋亡核 非嵌入式控件。琼脂糖包埋的组织块 感染HIV-1病毒的人。淋巴组织的长期培养 与外周淋巴细胞一起在两个隔室系统中， 与成像技术相结合，使我们能够模拟高 免疫系统的复杂程度和解决基本问题 淋巴细胞迁移、归巢和动力学。在没有动物的情况下 各种免疫紊乱的模型，包括艾滋病毒感染导致 艾滋病模型的建立为研究其发病机制提供了独特的系统 在人类淋巴组织中。

Continuing to develop imaging and culturing techniques for three- dimensional multicellular systems, we have grown live blocks of human and mouse lymphoid tissue in a low shear force rotating wall vessel bioreactor (RWV). Fragments of lymphoid tissue remain viable in the RWV for at least two weeks. Cells from the tissue migrate into the surrounding media. Migration of cells out of the tissue is reversible: labelled cells from the peripheral media re-populate the tissue and their fate can be followed by imaging with confocal microscopy. Migration of cells may be partially prevented by embedding the tissue fragments in collagen gels. Cell migration is completely stopped when the tissues are embedded in agarose gels. Agarose-embedded blocks of tissue remain alive: they consume oxygen and glucose, produce IgG into the media and retain the basic elements of their architecture, including B cell-rich germinal centers surrounded by T cells. Tall densities are similar that of tissue blocks cultured on the top of the gels (histocultures). Confocal imaging of agarose-embedded blocks of tissue reveal a network of follicular-dendritic cells in germinal centers. Agarose-embedded blocks of tissues retain more cells and have less apoptotic nuclei than non-embedded controls. Agarose-embedded blocks of tissues are productively infected with HIV-1. Long-term culturing of lymphoid tissue together with peripheral lymphocytes in a two-compartment system, in combination with the imaging technique, allows us to simulate the high level of complexity of the immune system and to address basic questions of lymphocyte migration, homing and kinetics. In the absence of animal models for various immune disorders, including HIV infection leading to AIDS, the developed model provides a unique system to study pathogenesis in human lymphoid tissue.