Nguyen Van Anh, Ebner Susanne, Fürhapter Christina, Romani Nikolaus, Kölle Dieter, Fritsch Peter, Sepp Norbert
Department of Dermatology and Venereology, University of Innsbruck, Innsbruck, Austria.
Eur J Immunol. 2002 Dec;32(12):3638-50. doi: 10.1002/1521-4141(200212)32:12<3638::AID-IMMU3638>3.0.CO;2-C.
DC are sentinels of the immune system. In order to reach the skin, bone-marrow-derived DC precursors need to bind and migrate through microvascular endothelial cells. Binding of DC toprimary endothelial cells of the skin has not been investigated. We therefore determined adhesion of DC at different stages of development to human dermal microvascular endothelial cells (HDMEC). DC were derived from CD34+ progenitors in cord blood. To enhance DC maturation, a defined cocktail of IL-1beta+IL-6+TNF-alpha+PGE2 was applied. Adhesion was quantified by fluorimetric and phase-contrast microscopical assays. Significantly more DC precursors (tested on day 5 after isolation) than mature DC (spontaneously matured or cytokine-cocktail-matured and tested on day 13) bound to unstimulated HDMEC. In contrast, the maturation stage of DC had no influence on their binding to human umbilical vein endothelial cells. Pretreatment of HDMEC with TNF-alpha and IFN-gamma resulted in an enhanced attachment of both DC precursors and mature DC. Mature DC lacked expression of CD31, CD36, CD45RA and CLA, and expressed lower levels of CD11a, CD11b and CD49d as compared with precursors tested on day 5. mAb against CD18, CD11a, CD11b, and CD36 markedly inhibited DC binding, whereas anti-CLA, anti-DC-SIGN, anti-CD29 and anti-CD49 mAb did not. Our data support the hypothesis of immunosurveillance with selective recruitment of blood DC precursors to resting and, more so, to inflamed skin. The data have potential relevance for anti-cancer immunotherapy strategies favoring the intracutaneous application of mature DC.
树突状细胞（DC）是免疫系统的哨兵。为了到达皮肤，源自骨髓的DC前体细胞需要与微血管内皮细胞结合并迁移。DC与皮肤原发性内皮细胞的结合尚未得到研究。因此，我们测定了不同发育阶段的DC与人真皮微血管内皮细胞（HDMEC）的粘附情况。DC来源于脐带血中的CD34+祖细胞。为了增强DC的成熟，应用了IL-1β+IL-6+TNF-α+PGE2的特定组合。通过荧光和相差显微镜测定法对粘附进行定量。与成熟DC（自发成熟或经细胞因子组合成熟并在第13天进行检测）相比，显著更多的DC前体细胞（在分离后第5天进行检测）与未刺激的HDMEC结合。相比之下，DC的成熟阶段对其与人脐静脉内皮细胞的结合没有影响。用TNF-α和IFN-γ预处理HDMEC导致DC前体细胞和成熟DC的附着均增强。与第5天检测的前体细胞相比，成熟DC缺乏CD31、CD36、CD45RA和CLA的表达，并且CD11a、CD11b和CD49d的表达水平较低。抗CD18、CD11a、CD11b和CD36的单克隆抗体显著抑制DC的结合，而抗CLA、抗DC-SIGN、抗CD29和抗CD49单克隆抗体则没有。我们的数据支持免疫监视的假说，即血液中的DC前体细胞被选择性招募到静止的皮肤，尤其是炎症皮肤。这些数据对于支持成熟DC皮内应用的抗癌免疫治疗策略具有潜在的相关性。
