Hanau D, Fabre M, Schmitt D A, Lepoittevin J P, Stampf J L, Grosshans E, Benezra C, Cazenave J P
INSERM U.311, Centre Régional de Transfusion Sanguine, Strasbourg, France.
J Invest Dermatol. 1989 May;92(5):689-94. doi: 10.1111/1523-1747.ep12696879.
We have previously described an ATPase Langerhans cell (LC) staining technique allowing progression from light to electron microscope observation. Using this technique we have studied, following epicutaneous application of a sensitizing dose of a hapten, 2,4-dinitro-1-fluorobenzene (DNFB), the fate of the epidermal LC located in the sensitization zone. We wanted to know, under the light microscope, if the density and/or morphology of the LC are modified by such a treatment and, under the electron microscope, what are the ultrastructural changes accompanying the possible light microscope modifications. Under the light microscope, the observation of LC during the 5 d necessary for the development of contact sensitivity to DNFB shows that their number drops in the course of the first 24 h to normalize again 3 d later. Under the electron microscope, observations over the first 24 h revealed that LC remained in the epidermis, but were ATPase-negative. The disappearance of the membrane ATPase activity took place while the LC presented an increased number of coated pits, coated vesicles, endosomes, and lysosome organelles which characterize, at the ultrastructural level, the process of receptor-mediated endocytosis (RME). Following RME, many Birbeck granules (BG) appeared in the cytoplasm. Thus, epicutaneous application of DNFB leads to an endocytic activation of LC. However, the ligand(s) and/or the cell-surface components, which probably internalize during the RME process, remain unknown.
我们之前描述了一种朗格汉斯细胞（LC）的ATP酶染色技术，该技术可实现从光学显微镜观察到电子显微镜观察的递进。利用这一技术，我们在经皮应用致敏剂量的半抗原2,4-二硝基-1-氟苯（DNFB）后，研究了位于致敏区域的表皮LC的命运。我们想通过光学显微镜了解这种处理是否会改变LC的密度和/或形态，以及通过电子显微镜了解伴随可能的光学显微镜改变的超微结构变化是什么。在光学显微镜下，对DNFB接触敏感性发展所需的5天内LC的观察表明，其数量在最初24小时内下降，3天后再次恢复正常。在电子显微镜下，最初24小时的观察显示LC仍留在表皮中，但呈ATP酶阴性。膜ATP酶活性消失的同时，LC呈现出数量增加的被膜小窝、被膜小泡、内体和溶酶体细胞器，这些在超微结构水平上表征了受体介导的内吞作用（RME）过程。RME之后，许多伯贝克颗粒（BG）出现在细胞质中。因此，经皮应用DNFB会导致LC的内吞激活。然而，在RME过程中可能内化的配体和/或细胞表面成分仍然未知。
