Department of Dermatology, Leiden University Medical Center, PO Box 9600, Leiden, 2300 RC, the Netherlands.
Br J Dermatol. 2014 Sep;171(3):499-504. doi: 10.1111/bjd.12934. Epub 2014 Aug 21.
Histological differentiation between Sézary syndrome (SS) and erythrodermic inflammatory dermatoses (EID) can be very difficult. Recent studies show that programmed death-1 (PD-1) is strongly expressed by the neoplastic cells in skin biopsies of SS, while similar studies in EID are lacking.
To determine whether the number and distribution of PD-1(+) T cells could be used as an adjunct in the differentiation between SS and EID.
Expression of PD-1 and a panel of T-cell markers was investigated in skin biopsies from 30 patients with various types of EID (12 idiopathic, 10 atopic, six psoriatic and two paraneoplastic) and 25 patients with SS.
Expression of PD-1 by > 50% of the infiltrating T cells was observed in 23 of 25 (92%) SS cases and in only four of 30 (13%) EID cases. PD-1 is expressed by neoplastic CD4(+) T cells in SS, while in contrast, PD-1 was predominantly expressed by dermal and epidermal CD8(+) T cells in EID. Expression of CD7 by ≤ 20% of the infiltrating T cells was observed only in SS (13 of 24; 54%), and not in any of the 30 cases of EID.
While PD-1 is expressed by CD4(+) neoplastic T cells in SS, our results suggest that PD-1 is expressed mainly by activated dermal and epidermal CD8(+) T cells in EID. Expression of PD-1 by > 50% of CD4(+) T cells and expression of CD7 by ≤ 20% of the infiltrating T cells strongly support a diagnosis of SS in skin biopsies of patients with erythroderma.
蕈样肉芽肿（SS）和红皮病性炎症性皮肤病（EID）之间的组织学分化可能非常困难。最近的研究表明，程序性死亡受体-1（PD-1）在 SS 皮肤活检中的肿瘤细胞中强烈表达，而在 EID 中缺乏类似的研究。
确定 PD-1（+）T 细胞的数量和分布是否可作为辅助诊断 SS 和 EID 的手段。
在 30 例不同类型 EID（12 例特发性、10 例特应性皮炎、6 例银屑病和 2 例副肿瘤性）和 25 例 SS 患者的皮肤活检中，研究了 PD-1 和一组 T 细胞标志物的表达。
在 25 例 SS 病例中有 23 例（92%）观察到 >50%的浸润 T 细胞表达 PD-1，而在 30 例 EID 病例中仅有 4 例（13%）。PD-1 在 SS 中的肿瘤性 CD4+T 细胞中表达，而相反，PD-1 在 EID 中主要由真皮和表皮 CD8+T 细胞表达。仅在 SS（24 例中的 13 例；54%）中观察到浸润 T 细胞中 CD7 的表达≤20%，而在 30 例 EID 病例中均未观察到。
虽然 PD-1 在 SS 中的肿瘤性 CD4+T 细胞中表达，但我们的结果表明，PD-1 在 EID 中主要由活化的真皮和表皮 CD8+T 细胞表达。皮肤活检中浸润 T 细胞中 CD4+T 细胞的 PD-1 表达>50%，浸润 T 细胞的 CD7 表达≤20%，强烈支持诊断为 SS。
