Bigby M, Kwan T, Sy M S
Department of Pathology, Harvard Medical School, Boston, MA 02115.
J Invest Dermatol. 1987 Nov;89(5):495-9. doi: 10.1111/1523-1747.ep12460983.
We have initiated a series of studies in vivo to investigate the physiologic role of Langerhans cells and Thy-1+ dendritic epidermal cells in the development and regulation of contact hypersensitivity. The density of I-A+ Langerhans cells and Thy-1+ dendritic epidermal cells in ammonium thiocyanate-separated epidermal sheets was determined in ten strains of inbred mice using immunofluorescence microscopy with monoclonal anti-I-A and anti-Thy-1 antibodies. Mice of different inbred strains were sensitized by painting the left ear with varying doses of either oxazolone or trinitrochlorobenzene. From five to 20 days after sensitization, groups of mice were challenged with the relevant antigen and the intensity of contact hypersensitivity, as measured by ear swelling, was determined. We then determined whether the intensity and/or duration of contact hypersensitivity in different strains of mice was influenced by the density of Thy-1+ dendritic epidermal cells or the ratio of I-A+ Langerhans cells to Thy-1+ dendritic epidermal cells. We found that there was marked variability in the density of Thy-1+ dendritic epidermal cells and I-A+ Langerhans cells in the ten strains of mice studied. The ratio of I-A+ Langerhans cells to Thy-1+ dendritic epidermal cells ranged from 0.5 in C57BL/10J mice to greater than 22 in A/J and BALB/cByJ mice. When small amounts of contact sensitizers were used to induce contact hypersensitivity (e.g., 20 micrograms of oxazolone or trinitrochlorobenzene), there was consistent strain variability in the intensity of ear swelling. There was a significant correlation between the ratio of I-A+ Langerhans cells to Thy-1+ dendritic epidermal cells and the intensity of contact hypersensitivity (Pearson's correlation coefficient 0.85, p = 0.002). Strains with the highest ratios of I-A+ Langerhans cells to Thy-1+ dendritic epidermal cells had the most ear swelling. There were no consistent differences in the duration of contact hypersensitivity observed among the ten different strains. Our results indicate that Thy-1+ dendritic epidermal cells may play a physiologic role in down-regulating contact hypersensitivity in vivo.
我们已开展了一系列体内研究，以探究朗格汉斯细胞和Thy-1⁺树突状表皮细胞在接触性超敏反应的发生发展及调节过程中的生理作用。使用抗I-A和抗Thy-1单克隆抗体，通过免疫荧光显微镜法，测定了十品系近交系小鼠中硫氰酸铵分离的表皮片中I-A⁺朗格汉斯细胞和Thy-1⁺树突状表皮细胞的密度。用不同剂量的恶唑酮或三硝基氯苯涂抹不同近交系小鼠的左耳进行致敏。致敏后5至20天，用相关抗原对小鼠组进行激发，并通过耳部肿胀测定接触性超敏反应的强度。然后我们确定了不同品系小鼠接触性超敏反应的强度和/或持续时间是否受Thy-1⁺树突状表皮细胞密度或I-A⁺朗格汉斯细胞与Thy-1⁺树突状表皮细胞比例的影响。我们发现，在所研究的十品系小鼠中，Thy-1⁺树突状表皮细胞和I-A⁺朗格汉斯细胞的密度存在显著差异。I-A⁺朗格汉斯细胞与Thy-1⁺树突状表皮细胞的比例在C57BL/10J小鼠中为0.5，在A/J和BALB/cByJ小鼠中大于22。当使用少量接触性致敏剂诱导接触性超敏反应时（例如20微克恶唑酮或三硝基氯苯），耳部肿胀强度存在一致的品系差异。I-A⁺朗格汉斯细胞与Thy-1⁺树突状表皮细胞的比例与接触性超敏反应的强度之间存在显著相关性（皮尔逊相关系数0.85，p = 0.002）。I-A⁺朗格汉斯细胞与Thy-1⁺树突状表皮细胞比例最高的品系耳部肿胀最明显。在十个不同品系中，接触性超敏反应的持续时间未观察到一致的差异。我们的结果表明，Thy-1⁺树突状表皮细胞可能在体内下调接触性超敏反应中发挥生理作用。
