Picut C A, Lee C S, Lewis R M
Br J Dermatol. 1987 Jun;116(6):773-84. doi: 10.1111/j.1365-2133.1987.tb04895.x.
Ultrastructural changes of murine Langerhans cells (LC) were examined following exposure of crude epidermal cell suspensions to the contact allergens dinitrochlorobenzene, nickel sulphate and lead nitrate at various concentrations and for various incubation times. An immunogold labelling technique was employed to study changes in surface expression of MHC Class II (Ia) molecules. In all cases, activation of LC was evident after as little as 15 min exposure and was characterized by a marked increase in surface expression of Ia molecules, prominent rough endoplasmic reticulum and numerous ribosomes and lysosomes. Degenerative changes in LC were apparent to varying degrees depending on the allergen, its concentration and the time of incubation. Degenerative changes included swollen mitochondria, membrane disruption or rupture, loss of density of the cytoplasm (cytolysis), loss of dendritic processes and decreased expression of Ia molecules. In the case of dinitrochlorobenzene, degenerative changes were present and usually severe at concentrations greater than 10 micrograms/ml, while exposure to nickel sulphate and lead nitrate was associated with only mild degenerative changes. These observations indicate that contact allergens have a variety of direct effects on LC, including activation and degeneration, which are dose- and time-dependent. Since these alterations of LC were observed in the absence of other immunologically active cells, peripolesis cannot be involved in these events.
将粗制表皮细胞悬液暴露于不同浓度的接触性变应原二硝基氯苯、硫酸镍和硝酸铅，并孵育不同时间后，检测了小鼠朗格汉斯细胞（LC）的超微结构变化。采用免疫金标记技术研究主要组织相容性复合体II类（Ia）分子表面表达的变化。在所有情况下，暴露仅15分钟后LC的激活就很明显，其特征是Ia分子表面表达显著增加、粗面内质网突出以及有大量核糖体和溶酶体。根据变应原、其浓度和孵育时间的不同，LC的退行性变化程度各异。退行性变化包括线粒体肿胀、膜破坏或破裂、细胞质密度丧失（细胞溶解）、树突状突起丧失以及Ia分子表达减少。就二硝基氯苯而言，浓度大于10微克/毫升时会出现退行性变化且通常较为严重，而暴露于硫酸镍和硝酸铅仅伴有轻度退行性变化。这些观察结果表明，接触性变应原对LC有多种直接影响，包括激活和退变，且这些影响具有剂量和时间依赖性。由于在没有其他免疫活性细胞的情况下观察到了LC的这些改变，因此细胞周缘运动不可能参与这些事件。
