McGregor J M, Barker J N, Ross E L, MacDonald D M
Laboratory of Applied Dermatopathology, United Medical School, London, U.K.
J Am Acad Dermatol. 1992 Sep;27(3):383-8. doi: 10.1016/0190-9622(92)70203-r.
Epidermal dendritic cells (DCs) isolated from psoriasis possess greatly enhanced T lymphocyte-activating properties compared with DCs from normal skin, suggesting that DCs in psoriasis express surface antigens crucial for antigen presentation. These include beta 2-integrins and intercellular adhesion molecule (ICAM)-1.
Our purpose was to determine DC phenotype in psoriatic compared with normal epidermis with respect to these molecules.
Tissue sections were single labeled with a peroxidase antiperoxidase (PAP) immunohistochemical technique and double labeled where necessary with a combination of a PAP and an alkaline phosphatase-anti-alkaline phosphatase technique.
In psoriatic compared with normal skin, decreased numbers of DCs expressed CD1a (p less than 0.05), whereas increased numbers of DCs expressed class II major histocompatibility antigens (p less than 0.05). In normal skin positive staining for CD18 was not observed, whereas in psoriasis both CD1a+ and CD1a- DCs expressed beta 2-integrins, LFA-1 (CD11a/CD18), and gp 150/95 (CD11c/CD18). DCs in atopic dermatitis and lichen planus were also found to express beta 2-integrins. Neither MAC 1 (CD11b/CD18) nor ICAM-1 was observed on DCs.
These data are consistent with either migration of dendritic antigen-presenting cells into the epidermis or in situ cytokine modulation of Langerhans cell phenotype in inflamed skin. Furthermore, they indicate that epidermal DCs in psoriasis and other cutaneous inflammatory diseases express molecules that are known to be crucial for Langerhans cell-driven T-cell activation in vitro.
与正常皮肤来源的树突状细胞（DCs）相比，从银屑病中分离出的表皮树突状细胞具有大大增强的T淋巴细胞激活特性，这表明银屑病中的树突状细胞表达了对抗抗原呈递至关重要的表面抗原。这些抗原包括β2整合素和细胞间粘附分子（ICAM）-1。
我们的目的是确定银屑病与正常表皮中这些分子相关的DC表型。
组织切片采用过氧化物酶抗过氧化物酶（PAP）免疫组织化学技术进行单标记，并在必要时采用PAP和碱性磷酸酶抗碱性磷酸酶技术联合进行双标记。
与正常皮肤相比，银屑病中表达CD1a的DC数量减少（p<0.05），而表达II类主要组织相容性抗原的DC数量增加（p<0.05）。在正常皮肤中未观察到CD18的阳性染色，而在银屑病中，CD1a+和CD1a-DC均表达β2整合素、淋巴细胞功能相关抗原-1（LFA-1，CD11a/CD18）和gp150/95（CD11c/CD18）。特应性皮炎和扁平苔藓中的DC也被发现表达β2整合素。DC上未观察到巨噬细胞抗原1（MAC 1，CD11b/CD18）和ICAM-1。
这些数据与树突状抗原呈递细胞迁移到表皮或炎症皮肤中朗格汉斯细胞表型的原位细胞因子调节一致。此外，它们表明银屑病和其他皮肤炎症性疾病中的表皮DC表达了已知在体外对朗格汉斯细胞驱动的T细胞激活至关重要的分子。
