银屑病皮损CD8αα^＋T细胞表型鉴定

Phenotype identification of CD8αα^＋T cells infiltrating psoriatic skin lesions

目的 探究银屑病皮损局部浸润的CD8^＋T细胞表型及其在银屑病发病中的作用。方法收集2017年1-12月第四军医大学西京皮肤医院明确诊断的8例进行期斑块状银屑病患者皮损，男女各4例，年龄24～50岁。8例健康对照皮肤来源于整形外科手术剩余皮肤，男女各4例，年龄23-46岁。采用免疫荧光技术检测皮损CD8^＋T细胞的分布及亚群比例，鉴定其免疫学表型及炎症因子白细胞介素（IL）17A的表达。结果 8例银屑病皮损真、表皮均可见CD8^＋T细胞浸润，其中CD8αα^＋T细胞表型占88．48％±7．39％，8例健康人皮肤局部仅有个别CD8^＋T细胞浸润，其中CD8αα^＋T细胞表型占14．43％±13．14％，两组比较，t：11．5，P〈0．01。银屑病皮损表皮CD8αα^＋T细胞表达组织局部定植标志CDl03，真皮CD8αα^＋T细胞不表达CDl03。银屑病皮损CD8αα^＋T细胞表达CD45RA-CCR7-效应记忆性T细胞表型，不表达CD8^＋调节性T细胞标志Foxp3、CD25和CDl22。银屑病皮损CD8αα^＋T细胞中分泌IL-17A的细胞比例为24．85％±4．25％，对照组CD8αα^＋T细胞不分泌IL-17A，两组差异有统计学意义（t=5．853，P〈0．01）。结论 银屑病皮损浸润的CD8αα^＋T细胞是效应记忆性T细胞，可能通过分泌IL-17A参与银屑病的发生发展。

Objective To identify the phenotype of CD8ctαα^＋T cells locally infiltrating psoriatic skin lesions, and to investigate their role in the occurrence of psoriasis. Methods Skin lesions were obtained from 8 patients with confirmed plaque psoriasis in the progressive stage, who visited the Department of Dermatology in Xijing Hospital affiliated to the Fourth Military Medical University from January to December in 2017. Of the 8 patients, 4 were male and 4 were female, with ages ranging from 24 to 50 years. Normal skin tissues were obtained from discarded skin tissues of 8 healthy controls in plastic surgery. Of the 8 healthy controls, 4 were male and 4 were female, with ages ranged from 23 to 46 years. Immunofluorescence technique was used to investigate the distribution of CD8αα^＋ T cells, determine the proportion of CD8cm~＋ T cell subsets, identify the immunological phenotype of CD8αα^＋T cells and measure the expression of interleukin- 17A （IL- 17A）. Results Infiltration of CD8 ＋ T cells was observed in the dermis and epidermis of the 8 psoriatic skin lesions, and the proportion of CD8c^a＋ T cells was 88.48% ~ 7.39%. However, only a few CD8~ T cells locally infiltrated the control skin tissues, and the proportion of CD8t^c~＋ T cells was 14.43% _＋ 13.14%. There was a significant difference in the proportion of CD8ctc~＋ T cells between the psoriatic skin lesions and control skin tissues （t = 11.5, P 〈 0.01 ）. CD8act＋ T cells in the psoriatic epidermis expressed CD103 （a marker of tissue-resident cells）, while CD8cαα^＋T cells in the psoriatic dermis did not express CD103. CD8αα^＋T cells in the psoriatic lesions were identified as CD45RA-CCR7-effector T cells, and did not express Foxp3, CD25 and CD122 （markers of CD8＋ regulatory T cells）. The proportion of CD8αα^＋T cells producing IL-17A in the psoriatic lesions was 24.85% -＋ 4.25%, while CDαα^＋T ceils in the control skin tissues did not produce IL-17A. There was a significant difference in the proportion of CD8cto~＋ T cells producing IL-17A between the psoriatic skin lesions and control skin tissues （t = 5.853, P 〈 0.01 ）. Conclusion CD8αα^2T cells infiltrating psoriatic lesions are effeetor memory T cells, and may contribute to the occurrence and development of psoriasis by oroducing IL-17A.scent antibody technique