自然杀伤细胞和T淋巴细胞在银屑病发病中作用的研究

用免疫组化法检测10例银屑病患者皮损、皮损周围外观正常皮肤和正常对照组自然杀伤细胞（NK细胞）、T细胞表面抗原的表达。结果表明：患者皮损处真皮乳头NK细胞表面抗原CD16、CD56、CD57、CD94、CD158a，T细胞表面抗原CD2、CD3、CD4、CD8和皮肤白细胞相关抗原（CLA）阳性表达的细胞数，较皮损周围外观正常皮肤和正常对照组增多（P＜0．05或＜0．01）。作者认为：T细胞、NK细胞共同参入银屑病的发病，并分析了二者之间相互关系。     

Immunopathogenesis of psoriasis: focus on natural killer T cells

Psoriasis is a common inflammatory skin disease triggered by dysregulated immune response and characterized by hyperproliferation and altered differentiation of keratinocytes. Formation of psoriatic lesions is thought to be elicited by the complex cellular and cytokine network arising from the pathogenic interactions between keratinocytes and components of innate and acquired immune system. Natural killer T (NKT) cells are a heterogenous T-cell lineage that has been implicated in the pathogenesis of various autoimmune diseases including psoriasis. Due to the numerous functions of NKT cells that link innate and adaptive immunity, their role in psoriasis is complex and still elusive. We summarize the currently available literature data on this issue and discuss the possible role of NKT cells in the immunopathogenesis of this autoimmune disease.     

The effects of phototherapy on the numbers of circulating natural killer cells and T lymphocytes in psoriasis

The innate immune system is believed to be important in the pathogenesis of psoriasis and natural killer (NK) have been found in increased numbers in psoriatic plaques. Alterations in the numbers of NK cells in peripheral blood have been reported. We investigated the effect of phototherapy on levels of peripheral NK cells and lymphocytes in patients with psoriasis. In nine patients whom we followed before, during and after narrowband ultraviolet B (UVB) treatment there were no differences in the numbers of circulating lymphocytes, lymphocyte subsets or cells expressing NK markers and controls. Treatment with narrowband UVB did, however, significantly lower circulating CD4 counts which gradually recovered posttreatment.     

Upregulation of Fas and downregulation of CD94/NKG2A inhibitory receptors on circulating natural killer cells in patients with new-onset psoriasis

Background  Psoriasis has been considered as a T-helper 1 cell-mediated autoimmune disease driven by collaboration with multiple components of innate and acquired immune cells. Natural killer (NK) cells have been shown to bridge innate and acquired immunity, and thus could potentially contribute to the pathophysiology of psoriasis.
Objectives  To investigate the phenotypic changes of circulating NK cells in patients with new-onset psoriasis.
Methods  Fifteen patients with plaque psoriasis (eight women and seven men) who visited our clinic after their first episode of psoriasis and did not have a history of previous systemic therapy or phototherapy participated in this study. Peripheral blood mononuclear cells were isolated and stained with a panel of antibodies against cell surface receptors expressed on T and/or NK cells and analysed by flow cytometry.
Results  As compared with normal healthy volunteers, patients with new-onset psoriasis showed no significant changes in numbers of peripheral NK, NK-T or T cells. NK activating receptors 2B4, CD48, NKG2D, CD16 and CD56 were found to be unchanged in new-onset psoriasis. However, the expression of Fas (activation-induced death receptor) was upregulated, whereas the expression of the NK inhibitory receptors CD94 and NKG2A was dramatically reduced on NK cells of new-onset psoriasis. These changes occurred at the level of mean fluorescent intensity, but minimally affected percentages of cells expressing Fas, CD94 and NKG2A.
Conclusions  Our findings demonstrate that changes in the expression of Fas and CD94/NKG2A receptors on NK cells may occur during new-onset psoriasis, and are likely to contribute to the pathogenesis of psoriasis.     

Blastic natural killer cell and extranodal natural killer cell-like T-cell lymphoma presenting in the skin: report of six cases from the UK

BACKGROUND: Some lymphomas express natural killer (NK)-cell markers such as the neural cell adhesion molecule, which is recognized by the CD56 antibody. These lymphomas may present in the skin, but do not represent a homogeneous group. The new World Health Organization classification of lymphoma/leukaemia recognizes several types of NK/T-cell neoplasm, including blastic NK-cell lymphoma, which characteristically presents with cutaneous lesions. OBJECTIVES: To describe the clinical, pathological and molecular features in six cases of CD56+ lymphoma with cutaneous presentation. METHODS: The clinical, histopathological and immunophenotypic features of six patients were reviewed. In addition, in situ hybridization (ISH) to identify Epstein-Barr virus (EBV) mRNA, and polymerase chain reaction analysis to identify the presence of a clonal population of T cells or B cells were performed on lesional skin. RESULTS: All patients presented with widespread nodules and plaques, which in five cases were a characteristic purple colour. Four patients developed disseminated disease, three with neurological involvement. These four patients died between 14 and 46 months following diagnosis (median 30 months). In four of six cases the histopathological and immunohistological features were in keeping with a blastic NK-cell lymphoma. No clonal immunoglobulin heavy chain (IgH) or T-cell receptor (TCR) gene rearrangement was detected in the four cases consistent with an origin from NK cells. A further case fitted the criteria for an extranodal NK/T-cell lymphoma of nasal type and was also the only case to show evidence of EBV mRNA by ISH. A clonal T-cell population was identified in the final case. This patient also exhibited molecular evidence of a clonal B-cell population and a t(14;18) translocation confirmed by sequence analysis. CONCLUSIONS: Our data confirm that NK-cell lymphomas presenting in the skin are a heterogeneous group, and that in the U.K., blastic NK-cell lymphoma is more common than extranodal NK/T-cell lymphoma of nasal type. These lymphomas pursue an aggressive course, with rapid development of disseminated disease, and resistance to chemotherapy. Detailed immunophenotyping is needed to distinguish the different types. Our molecular data indicate that blastic NK-cell lymphoma cases lack clonal TCR/IgH gene rearrangements consistent with an NK-cell origin. Our ISH findings indicate that EBV plays a pathogenetic role only in extranodal NK/T-cell lymphoma of nasal type.     

Memory effector (CD45RO+) and cytotoxic (CD8+) T cells appear early in the margin zone of spreading psoriatic lesions in contrast to cells expressing natural killer receptors, which appear late

BACKGROUND: An influx of immunocytes, increased epidermal proliferation and abnormal keratinization are hallmarks of the psoriatic lesion. T-lymphocyte subsets in particular activated effector memory T cells and natural killer (NK) T cells have been suggested to play an important role in the pathogenesis of psoriasis. OBJECTIVES: In the present study we investigated the number of T-cell subsets (CD4, CD8, CD45RO, CD45RA, CD2, CD25), cells expressing NK receptors (CD94 and CD161), the proliferation marker Ki67 and the keratinization marker keratin (K10) across the margin of the spreading psoriatic plaque: distant uninvolved skin, the outer margin (immediately outside the clinical edge), the inner margin (immediately inside the clinical edge) and the central area. PATIENTS AND METHODS: Eight patients with active psoriasis vulgaris participated in this study. Biopsies were taken from the spreading psoriatic lesion from the distant uninvolved skin, the outer margin, the inner margin and the central area. Biopsies were processed for immunohistochemical staining. RESULTS: In the outer margin CD8+ (cytotoxic T cells) and CD45RO+ (memory effector T cells) T lymphocytes invade the epidermis and in this early stage the activation markers CD2 and CD25 also show a substantial increase. The next phase, from the outer to the inner margin, shows a statistically significant increase of these markers, and especially, the cells expressing NK receptors (CD94 and CD161) show a massive increase together with a significant increase of epidermal proliferation (Ki67) and a decrease of the K10+ epidermal surface. CONCLUSIONS: CD8+, CD45RO+, CD2+ and CD25+ T cells have a role in the early phase of the psoriatic process, whereas CD94- and CD161-expressing cells together with epidermal proliferation and keratinization are involved in a later phase.     

Blastic natural killer cell leukaemia with skin involvement: a case report

Natural killer cell leukaemia is generally accompanied by extramedullary involvement. CD4+ natural killer cell leukaemia frequently manifests with cutaneous involvement. The disease pursues a very aggressive course with no long-term survivors reported. We present a patient with CD4+ natural killer cell leukaemia with skin, bone marrow and peripheral blood involvement who is still on remission at the end of 2 years.     

银屑病患者维生素D受体基因多态性与外周血NK细胞、T淋巴细胞亚群分析

目的：探讨银屑眉病患者的维生素D受体(VDR)基因多态性与外周血自然杀伤(NK)细胞、T淋巴细胞亚群的关系。方法：采用聚合酶链反应(PCR）、限制性内切酶酶切技术(RFLP)，以及流式细胞仪对112例无血缘关系的银屑病患者和108名无血缘关系的健康人VDR基因型进行分析，并对其外周血NK、CD3、CD4、CD8细胞进行测定。结果：银屑病患者与健康人的VDR基因型的分布情况有明显不同，纯合子AA、杂合子Bb基因型在银屑病患者中出现的频率明显高于健康人。银屑病患者CD4、CD8细胞均显著高于健康人，而Bb基因型患者的NK细胞显著高于健康人，CD3细胞明显低于健康人．结论：纯合子AA基因型或杂合子Bh基因型的出现可能增加汉族人患银屑病的危险性。Bb基因型患者可能存在免疫缺陷。     

Increased expression of the natural killer cell inhibitory receptor CD94/NKG2A and CD158b on circulating and lesional T cells in patients with chronic plaque psoriasis

BACKGROUND: Psoriasis is a common inflammatory cutaneous disorder characterized by activated T-cell infiltration. T lymphocytes bearing natural killer cell receptors (NKRs) have been suggested to play an important role in the pathogenesis of psoriasis. However, the expression pattern of activating and inhibitory NKRs on T lymphocytes from psoriatic patients and its significance in psoriasis needs further study. OBJECTIVES: To investigate the pathogenesis of NKR-expressing T cells in psoriasis. MATERIALS AND METHODS: Thirty patients with chronic plaque psoriasis and 20 healthy controls were enrolled in this study. The immunophenotypic profiles of NKRs, including CD56, CD16 (activating NKRs), CD158a, CD158b, CD94 and NKG2A (inhibitory NKRs), were analysed in peripheral blood T lymphocytes, as well as psoriatic lesional infiltrating T cells, by triple-fluorescence flow cytometry. RESULTS: A significant increase of inhibitory CD8+ CD158b+, CD4 CD8 CD158b+ and CD8+ CD94/NKG2A+ T cells was found in the peripheral blood of patients with psoriasis when compared with controls. Tissue-infiltrating T lymphocytes expressing inhibitory receptors CD158b, CD94 and NKG2A were found in psoriatic lesions. There was a significant positive correlation between the increased percentage of circulating CD8+ CD94/NKG2A+ T cells and the Psoriasis Area and Severity Index. CONCLUSIONS: In the present study, we demonstrated increased proportions of particular subsets of inhibitory CD158b+ and/or CD94/NKG2A+ T cells in patients with psoriasis. The elevation of these inhibitory NKR-expressing T cells was correlated with disease severity, which may signify the possibility of chronic antigen-driven stimulation and dysregulated cytokine production in the pathogenesis of psoriasis.     

银屑病皮损区肥大细胞分布和血管内皮细胞CD34表达的研究

目的探讨肥大细胞(MC)和血管内皮细胞在银屑病发病中的作用.方法采用组织化学和免疫组化的方法,观察寻常性银屑病皮损处MC和CD34标记血管内皮细胞的分布情况.结果经甲苯胺蓝特殊染色发现,银屑病患者真皮区的MC密度在进行期(33.07±14.63)个/mm2,高于静止期(21.80±4.86)个/mm2,静止期又高于正常对照组(15.85±6.93)个/mm2,它们之间的差异均有显著性;免疫组化观察发现,银屑病真皮区CD34标记的微血管密度在进行期(2931±4.04)个/mm2,明显高于静止期(2231±2.07)个/mm2,而静止期又明显高于正常对照组(18.81±2.59)个/mm2.结论寻常性银屑病皮损处真皮内肥大细胞和血管内皮细胞密度明显增加,且与病情变化有关.     

Perforin expression is upregulated in the epidermis of psoriatic lesions

BACKGROUND: There are currently very few data regarding the role of cell-mediated cytotoxicity in psoriasis. Both cytotoxic T lymphocytes and natural killer (NK) cells mediate cytotoxicity reactions, mainly by two distinct pathways, the perforin/granzyme and the Fas/Fas ligand pathway. OBJECTIVES: To study the expression and distribution of perforin, T- and NK-cell subsets in psoriatic lesional and nonlesional skin. METHODS: Skin biopsy specimens from both lesional and nonlesional skin of 11 patients with chronic plaque psoriasis and eight healthy controls were analysed by immunohistochemistry. RESULTS: We found a significant increase in CD4+ and CD8+ cells in psoriatic lesions compared with nonlesional and healthy skin. The expression of CD16+ NK cells was significantly lower in lesions compared with healthy skin. Perforin expression was significantly enhanced in the epidermis of psoriatic lesions. CONCLUSIONS: Perforin expression is upregulated in the epidermis of psoriatic lesions, suggesting a potential role for perforin in the creation of the psoriatic plaque.     

MiRNA-203在寻常性银屑病皮损的表达及其对HaCaT细胞增殖的影响

目的 研究微小核糖核酸(miRNA)-203在寻常性银屑病患者皮损中的表达,并探讨对角质形成细胞株(HaCaT细胞)增殖的影响.方法 取2014-2016年23例寻常性银屑病患者的皮损组织和相邻非皮损组织.荧光定量PCR法检测组织中miRNA-203的表达水平,并以5'端、3'端地高辛标记的探针对皮肤组织切片中目的miRNA进行原位杂交,观察miRNA-203在皮肤组织中的定位情况.将miRNA-203模拟物(miRNA-203模拟物组)和miRNA-203模拟物阴性对照(阴性对照组)分别转染HaCaT细胞,正常细胞培养组作为空白对照组,采用噻唑蓝(MTT)法、流式细胞仪和Western印迹法分别对HaCaT细胞的增殖、细胞周期及相关周期蛋白(Cyclin D1、Cyclin B1)的变化进行检测.结果 miRNA-203特异性地表达在表皮的角质形成细胞中,除细胞核外,细胞质亦有表达,且寻常性银屑病患者皮损组织中miRNA-203表达水平(1.35±0.28)显著高于非皮损组织(0.52±0.09),差异有统计学意义(t=6.76,P=0.012).转染miRNA-203模拟物能抑制HaCaT细胞增殖(F=9.36,P=0.007),且空白对照组、阴性对照组和miRNA-203模拟物组HaCaT细胞增殖率均随时间的延长逐渐增加(F=18.68,P＜0.001).与阴性对照组和空白对照组相比,miRNA-203模拟物组HaCaT细胞被阻滞在G2/M期(G2/M期细胞比例:31.33％±4.56％比17.02％±3.53％、16.67％±3.32％,均P＜0.05),HaCaT细胞周期蛋白周期蛋白D1表达水平较高(1.15±0.13比0.52±0.05、0.56±0.07,均P＜0.05),而周期蛋白B1水平较低(0.43±0.08比0.93±0.16、0.91±0.0.15,均P＜0.05).结论 miRNA-203可能参与了寻常性银屑病的发生发展过程.     

Cutaneous presentation of steroid responsive blastoid natural killer cell lymphoma

CD56+ lymphomas derived from natural killer (NK) cell lineage are rarely encountered in Western populations and their clinical and pathological features have not been fully defined. The majority of reported cases are lymphomas of the nasal cavity, which are most commonly seen in Asia. A subtype of CD56+ lymphoma has recently been described (blastoid NK-cell lymphoma) which characteristically presents in older patients with cutaneous infiltrates and disease at other nodal and extranodal sites. We describe a case that correlates well with the clinicopathological features of blastoid NK-cell lymphoma. An unusual feature in our patient was that the cutaneous features of the lymphoma showed complete resolution shortly following commencement of oral steroid therapy.     

Evaluation of activatory and inhibitory natural killer cell receptors in non-segmental vitiligo: a flow cytometric study

Background Recent observations established the role of altered cellular immunity and autoimmune hypothesis in the pathogenesis of vitiligo. There have been several reports discussing T‐cell and natural killer (NK) cell populations, but NK cell receptors were not evaluated in vitiligo. Objective The purpose of this investigation was to assess the role of T and NK cells as well as activatory and inhibitory NK cell receptor alterations in the pathogenesis of vitiligo and whether any aberrations were correlated with clinical findings of the disease. Patients/methods Fifty‐three patients with non‐segmental vitiligo and 45 age‐ and sex‐matched healthy controls were enrolled in the study. The percentages of lymphocytes, granulocytes, monocytes and CD3, CD4, CD8, CD14, CD16, CD56, CD45, CD45RA, CD54RO, CD28, CD80, CD94, CD158a, KIR3DL‐1 receptors as well as CD94, CD158a, KIR3DL‐1 receptors on CD16⁺ cells were detected by using flow cytometry. The patient and control groups were compared in terms of the results of flow cytometric analysis, and the results were assessed regarding the type and activity of vitiligo. Results The percentages of CD16⁺CD56⁺, CD3⁺CD16⁺CD56⁺, CD8⁺ and CD45RO⁺ cells were significantly increased in vitiligo group compared with the controls. No difference was detected between the patients and control groups in percentages of CD3⁺, CD4⁺, CD3^?CD16⁺CD56⁺, CD28⁺, CD45⁺, CD45RA⁺, CD94⁺, CD158a⁺ and KIR3DL‐1⁺ cells. The percentage of CD16⁺CD158a⁺ cells was significantly decreased in a randomized selected group of vitiligo patients. There were no differences in percentage expression of studied cell surface antigens between patients in the active or stable period. CD3⁺ cells were significantly increased in generalized form, and CD45RO⁺ cells were significantly increased in acral/acrofacial form when compared with the other types of vitiligo. Conclusions These results indicate further evidence for T and NK cell abnormalities in non‐segmental vitiligo. The present data show that NK cell activation may be responsible in the pathogenesis of vitiligo in conformity with decreased inhibitory and increased activatory NK cell receptors.     

Lymphocytes and Langerhans cells in patch tests

The distribution of immunocompetent cells was analysed in allergic (nickel) and irritant (dithranol) patch tests using conventional transmission electron microscopy and labelling with monoclonal antibodies in an avidin-biotin immunoperoxidase study. The biopsies were taken 24 or 48 h after the allergen/irritant application. In allergic and irritant reactions, most inflammatory cells were OKT11 positive (pan T lymphocytes). The majority of these cells were also OKT4 positive (helper/inducer T lymphocytes), while the minority were OKT8 positive (suppressor/cytotoxic T lymphocytes). NK9 positive cells (natural killer cells) were observed in small numbers. The number of dendritic OKT6 and OKIal positive cells (Langerhans cells) in the epidermis was unaffected in allergic reactions. In irritant reactions, a normal number of OKT6 positive Langerhans cells was observed, while the number of OKIal positive cells had increased in the epidermis. Dithranol caused prominent fine structural changes in the mitochondria of the Langerhans cells, while the keratinocytes appeared largely unaffected. The present study indicates that allergic and irritant patch tests cannot be differentiated reliably using current immunohistopathological or electron microscopic techniques, in spite of the small differences observed.     

树突状细胞在银屑病中的研究进展

银屑病是一种免疫系统异常激活的慢性炎症性皮肤病,其确切发病机制尚不完全清楚,但近年来,免疫应答失调在银屑病病理生理中的作用日益受到重视.树突状细胞作为先天免疫细胞,通过调节炎症相关因子和信号通路,启动和调节T细胞的免疫反应,在银屑病的发病过程中发挥重要作用.本文旨在总结近期树突状细胞在银屑病发病过程中的研究进展,以探讨...