Background: T-cell infiltration in plaque psoriasis has recently been an important subject of investigation. Interestingly, comparative analyses of the disease-specific composition of the lesional T-cell infiltrate in...Background: T-cell infiltration in plaque psoriasis has recently been an important subject of investigation. Interestingly, comparative analyses of the disease-specific composition of the lesional T-cell infiltrate in plaque psoriasis and other inflammatory dermatoses have only sparsely been performed. Objectives: To compare plaque psoriasis vs. atopic dermatitis and lichen ruber planuswith respect to T-cell subsets, epidermal proliferation and keratinization. Patients and methods: Biopsies were taken from untreated lesional skin of patients, six with psoriasis, six with atopic dermatitis and six with lichen planus. T-cell subsets (CD4+, CD8+, CD45RO+, CD45RA+, CD2+, CD25+), an epidermal proliferation (Ki-67) and a keratinization marker (K10) were stained immunohistochemically and quantified using image analysis. Results: The high number of CD8+T cells (52±13 cells mm-1) found in the psoriatic epidermis was not found in the epidermis of atopic dermatitis (9±4), nor in the epidermis of lichen planus (34±10). The other T-cell subsets in the epidermis and dermis showed no statistically significant differences between psoriasis and atopic dermatitis. In contrast to the limited presence of CD4+, CD8+and CD2+in the psoriatic dermis (110±19, 27±9, 127±41, cells mm-1, respectively), more impressive numbers of these cells were observed in the dermis of lichen planus (300±53, 144±38, 272±48, respectively). CD45RO+memory effector T-cell counts were significantly higher in the epidermis of lichen planus (39±10) than in psoriasis (19±5). Psoriatic epidermis proved to have major keratinocyte hyperproliferation (247±26 cells mm-1 lamina basalis), as compared with atopic dermatitis (134±15) and lichen planus (128±20). Furthermore, a marked decreased expression of keratin 10 was observed in psoriasis (41%of epidermal area) contrary to atopic dermatitis (70%). Conclusions: Psoriatic epidermis exhibits a pronounced CD8+epidermotropism with accompanying epidermal hyperproliferation and abnormal keratinization, which changes are only minimally expressed in atopic dermatitis and lichen planus. In plaque psoriasis, substantially fewer activated CD4+and CD8+T cells in the dermis and less CD45RO+T cells in the epidermis are present in comparison with lichen ruber planus.展开更多
文摘Background: T-cell infiltration in plaque psoriasis has recently been an important subject of investigation. Interestingly, comparative analyses of the disease-specific composition of the lesional T-cell infiltrate in plaque psoriasis and other inflammatory dermatoses have only sparsely been performed. Objectives: To compare plaque psoriasis vs. atopic dermatitis and lichen ruber planuswith respect to T-cell subsets, epidermal proliferation and keratinization. Patients and methods: Biopsies were taken from untreated lesional skin of patients, six with psoriasis, six with atopic dermatitis and six with lichen planus. T-cell subsets (CD4+, CD8+, CD45RO+, CD45RA+, CD2+, CD25+), an epidermal proliferation (Ki-67) and a keratinization marker (K10) were stained immunohistochemically and quantified using image analysis. Results: The high number of CD8+T cells (52±13 cells mm-1) found in the psoriatic epidermis was not found in the epidermis of atopic dermatitis (9±4), nor in the epidermis of lichen planus (34±10). The other T-cell subsets in the epidermis and dermis showed no statistically significant differences between psoriasis and atopic dermatitis. In contrast to the limited presence of CD4+, CD8+and CD2+in the psoriatic dermis (110±19, 27±9, 127±41, cells mm-1, respectively), more impressive numbers of these cells were observed in the dermis of lichen planus (300±53, 144±38, 272±48, respectively). CD45RO+memory effector T-cell counts were significantly higher in the epidermis of lichen planus (39±10) than in psoriasis (19±5). Psoriatic epidermis proved to have major keratinocyte hyperproliferation (247±26 cells mm-1 lamina basalis), as compared with atopic dermatitis (134±15) and lichen planus (128±20). Furthermore, a marked decreased expression of keratin 10 was observed in psoriasis (41%of epidermal area) contrary to atopic dermatitis (70%). Conclusions: Psoriatic epidermis exhibits a pronounced CD8+epidermotropism with accompanying epidermal hyperproliferation and abnormal keratinization, which changes are only minimally expressed in atopic dermatitis and lichen planus. In plaque psoriasis, substantially fewer activated CD4+and CD8+T cells in the dermis and less CD45RO+T cells in the epidermis are present in comparison with lichen ruber planus.
