Epidermal CD8+ T cells reactive with group A streptococcal antigens in chronic plaque psoriasis

Chronic plaque psoriasis is a T cell mediated disease associated with group A streptococci (GAS). We have previously shown the presence of a psoriasis-specific dermal Th1 subset that recognizes GAS antigens. To assess whether GAS-reactive T cells are also present in lesional epidermis, fresh cell suspensions or T cell lines isolated from lesional epidermis of 33 psoriasis patients were stained for intracellular interferon-gamma after stimulation with GAS antigens. The patients were typed by PCR for HLA-DR7 and HLA-Cw6 expression. A subset of GAS-reactive CD8+ T cells (2.4% +/- 2.4) was found in 14/21 (67%) fresh cell suspensions. A smaller subset of GAS-reactive CD4+ T cells (0.9% +/- 0.9) was found in 13/21 (62%) fresh cell suspensions, which was expanded in the T cell lines. There was a significant inverse correlation between the proportions of GAS-reactive CD4+ and CD8+ T cells in the fresh suspensions (r = -0.48, P = 0.0277). The presence of GAS-reactive CD4+ or CD8+ T cells did not correlate with HLA-DR7 or HLA-Cw6 expression, respectively. This study has demonstrated GAS-reactive CD8+, and to a lesser extent CD4+, T cell subsets in psoriatic epidermis and provides further evidence that GAS antigens may play a role in the pathogenesis of chronic plaque psoriasis.     

Epidermal CD8+ T cells in chronic plaque psoriasis are Tc1 cells producing heterogeneous levels of interferon-gamma

The majority of epidermal CD8+ T cells in chronic plaque psoriasis are activated Tc1 cells producing interferon-gamma and no interleukin-4, a small proportion of which express NK-T receptors. To quantitate their level of cytokine production and characterize them further, CD8+ T cells were isolated from epidermal cell suspensions of lesional biopsies from 24 patients with chronic plaque psoriasis. T-cell lines (TCL) were established by culture of CD8+ T cells with feeders and IL-2 for 11 days and expansion with PHA. Ten TCL were stained for surface markers; 6 were cloned with PHA by limiting dilution. Interferon-gamma, interleukin-4 and interleukin-10 production was measured by ELISA after PMA/anti-CD3 activation of 15 TCL and 39 CD8+ T-cell clones. The 10 TCL stained were CD8alphabeta+ (93.3%), T-cell receptor-alphabeta+ (99.5%), costimulatory molecule CD28+ (90.1%), with a small CD8alphaalpha+ population (2.3%). No NK-T-cell receptor CD158a or CD158b expression was detected, whilst CD94 was expressed on 6.2% of cells in 6/9 TCL. All the TCL and 37/39 CD8+ T-cell clones produced interferon-gamma but no or minimal interleukin-4 or interleukin-10. The TCL produced a wide range of interferon-gamma levels (138 to 15,020 pg/ml). Clones from 3 patients showed low levels (60 to 1,410 pg/ml), from 2 patients high levels (6,105 to 43,040 pg/ml) and from 1 patient a wide range (405 to 36,010 pg/ml) of interferon-gamma production. Thus epidermal CD8+ Tc1 cells in chronic plaque psoriasis produce highly heterogeneous levels of interferon-gamma, which may reflect clinical diversity.     

CD4~+CD25~+调节性T细胞与Th17细胞在寻常型银屑病中的表达

目的:检测外周血中CD4~+CD25~+调节性T细胞(简称Treg细胞)与Th17细胞在寻常型银屑病(PV)中的表达。方法:34例寻常型银屑病患者,18例正常人作为对照。采用流式细胞术检测外周血中Treg细胞、FOXP3~+Treg细胞及Th17细胞的表达水平。结果:PV患者外周血中Treg细胞比例和FOXP3~+Treg细胞比例分别为(3.68±1.22)%和(0.53±0.19)%,低于正常对照组的(6.63±1.00)%和(0.76±0.14)%(P0.05)。Th17细胞比例为(2.20±0.78)%,高于正常对照组的(0.65±0.22)%(P0.05)。PV患者外周血中Treg细胞的表达与FOXP3~+Treg细胞的表达呈正相关(r=0.563,P0.05),而Treg细胞的表达与Th17细胞的表达呈负相关(r=-0.522,P0.05);Treg细胞和Th17细胞二者与PASI评分无相关性,与病程亦无相关性。结论:Treg细胞表达的减少及Th17细胞应答的增强,可能是导致PV免疫失衡的重要原因。     

Identification of lesional CD4+ CD25+ Foxp3+ regulatory T cells in Psoriasis

BACKGROUND: Depletion of CD4+ CD25+ Foxp3+ naturally occurring regulatory T cells (T(reg)) induces autoimmune phenomena. These cells have not yet been fully characterized in the skin of psoriatic patients. OBJECTIVES: To prove that the Zenon immunofluorescent labeling technique is suitable for the demonstration of co-localization of T-cell markers and in particular to show the distribution of T(reg) in psoriatic skin. METHODS: In biopsies derived from normal and psoriatic skin, CD4+ CD25+, CD4+ CD45RO+, CD8+ CD25+, CD8+ CD45RO+ and CD4+ CD25+ Foxp3+ cells in the dermis and in the epidermis were immunophenotyped, using a quantitative immunofluorescent labeling technique (Zenon), analyzed and compared using image analysis. RESULTS: The immunofluorescent labeling technique was shown to be an easy and reliable tool to demonstrate co-localization of T-cell markers. In psoriasis, all pathogenic T-cell subsets (CD4+ CD25+, CD4+ CD45RO+, CD8+ CD25+ and CD8+ CD45RO+ cells) were significantly increased in the dermis and in the epidermis, as compared to normal skin (all p < 0.05). Using this labeling technique we were able to reveal CD4+ CD25+ Foxp3+ T(reg) in psoriatic dermis, but not in the dermis of normal skin (p < 0.0001). CONCLUSIONS: The Zenon immunofluorescence technique in combination with image analysis is suitable for the demonstration of co-localization of T-cell markers in tissue. Increased numbers of pathogenic T cells (CD4+ CD25+, CD4+ CD45RO+, CD8+ CD25+ and CD8+ CD45RO+) were shown in the dermis and epidermis, whereas CD4+ CD25+ Foxp3+ T(reg) were identified in psoriatic skin with a predilection for the upper dermis.     

Lesional T cells and dermal dendrocytes in psoriasis plaque express increased levels of granulysin

Granulysin is a broad-spectrum potent antimicrobial peptide produced by the immunocytes. We determined granulysin levels in certain cutaneous inflammatory diseases and correlated expression of granulysin with the relative risks of secondary infections in these conditions. In immunohistochemistry stains a monoclonal antigranulysin antibody was used at 1:150 dilutions. Compared with atopic dermatitis and nummular eczema lesions where secondary infection with Staphylococcus aureus is very common, we found that a significantly increased number of granulysin-positive T cells (P < .01) were present in psoriatic plaques. Psoriasis plaques are heavily colonized with S aureus . It is a well-known observation that despite open cracks and fissures these plaques do not get infected. Increased levels of granulysin provide an explanation for relative immunity of psoriatic plaques against both gram-positive and gram-negative bacterial infections.     

Correlation of psoriasis activity with abundance of CD25+CD8+ T cells: conditions for cloning T cells from psoriatic plaques

The role of T cells in the pathogenesis of psoriasis is widely acknowledged. However, key aspects of their precise function in the disease as well as the relative pathogenic contribution of T-cell subsets are still unknown. T-cell clones have been isolated from psoriatic plaques but a study of conditions affecting the isolation and expansion of T-cell clones from psoriatic skin has not been reported to date. Here, we observe a correlation of disease activity with the frequency of the CD3(+)CD8(+)CD25(+) subset. We show that prolonged in vitro culture changes the phenotypic subset distribution of T-cell lines derived from psoriatic skin and that T-cell clones can be isolated by sorting of CD25(+) cells emigrated from skin fragments after 7 days. We evaluate various conditions affecting expansion of psoriatic T-cell clones in vitro and show that blocking apoptosis can facilitate proliferation of activated T-cell clones in vitro. Our results indicate a prominent role of the CD8(+)CD25(+) T-cell subset in disease pathogenesis and should be useful in the design of experiments aiming at a systematic analysis of the specificity of clones present in psoriatic plaques.     

寻常型银屑病患者外周血CD4~+CD25~+及CD8~+CD25~+细胞的检测

目的研究进展期寻常型银屑病患者外周血CD4+CD25+和CD8+CD25+调节性T细胞的数量变化及其在银屑病免疫病理学发病机制中的作用。方法应用流式细胞术对进展期寻常型银屑病患者外周血CD4+CD25+和CD8+CD25+调节性T细胞进行检测。结果进展期寻常型银屑病外周血CD4+CD25+细胞及CD8+CD25+调节性T细胞数量与正常对照组相比,均显著降低(P<0.05,P<0.005),而CD4+CD25+/CD8+CD25+比值无显著性差异(P>0.05)。结论寻常型银屑病的发病与CD4+CD25+和CD8+CD25+调节性T细胞的同步降低有关,与二者的比值无关。     

Skin CD4+ T cells produce interferon-gamma in vitro in response to streptococcal antigens in chronic plaque psoriasis

Recently, we have demonstrated that group A streptococcal antigen reactive T cells are present in the skin lesions of chronic plaque psoriasis. To determine the cytokine profile (interferon-gamma, interleukin-4 and interleukin-10) of these T cells in response to streptococcal antigens, T cell lines were cultured from untreated lesional skin of 13 patients with chronic plaque psoriasis and 12 patients with other inflammatory skin diseases. T cell lines were incubated with or without a sonicated heat-killed mixture of group A streptococcal isolates for 18 h in the presence of a transport inhibitor, stained for surface CD4 or CD8 and intracellular cytokine expression, and analyzed by flow cytometry. Psoriatic T cell lines were grown from 10 of 13 patients and were predominately CD4+ (64%-85%) with 10%-32% CD8+ T cells. Variable numbers of CD4+ T cells produced interferon-gamma (0.8%-35%, median 13.9) in eight of 10 T cell lines (p < 0.02). In contrast, CD4+ T cells in five of 12 T cell lines obtained from disease controls did not produce or produced minimal interferon-gamma in response to group A streptococcal isolates; this was significantly different from the psoriatic T cell lines (p < 0.05). Small numbers of interleukin-10 positive (0.8%-1.3%) and interleukin-4 positive (2.1%-2.5%) CD4+ T cells induced by group A streptococcal isolates were also present in two out of five and three out of five psoriatic T cell lines, respectively. This was significantly less in each case than the numbers of CD4+/interferon-gamma+ T cells (p < 0.05). Cytokine-positive CD8+ T cells were rarely observed. These findings demonstrate that a subpopulation of CD4+ T cells in chronic plaque psoriasis skin lesions produces interferon-gamma in response to streptococcal antigens and may be relevant to the pathogenesis of psoriasis.     

调节性T淋巴细胞和Th17细胞与银屑病的研究进展

银屑病是一种与T淋巴细胞相关的自身免疫性疾病,新近研究发现,除了与Th1细胞有关外,调节性T淋巴细胞尤其叉头/翅膀状螺旋转录因子诱导表达的调节性T细胞和Th17细胞在银屑病的发病过程中起着非常重要的作用。其中,叉头/翅膀状螺旋转录因子（＋）调节性T细胞平衡免疫抑制和免疫激活的转换在银屑病加重方面起到关键作用,Th17细胞分泌的细胞因子IL-17A、IL-17F、IL-22、IL-23、IL-36及肿瘤坏死因子α等在皮肤疾病发生发展中起到重要的作用。银屑病是由调节性T细胞和Th17细胞等多种免疫细胞和细胞因子共同参与的疾病。     

The role of lesional T cells in recalcitrant psoriasis during infliximab therapy

With infliximab therapy (anti-TNF-alpha) for plaque psoriasis, over 80% of patients reach > or = 75% PASI improvement in 10 weeks of treatment. We describe a patient with severe recalcitrant psoriasis who was treated with infliximab 5 mg/kg for 22 weeks. Rather than the expected improvement, this patient experienced an initial exacerbation, followed by the lack of efficacy over the entire 22-week period of treatment. Before, during and after treatment we performed immunohistochemical analyses on lesional biopsies, with respect to T cells, NK-T cells, epidermal growth and differentiation. We found a discrepancy between the clinical aggravation and marked reductions of lesional T cell subsets. The most prominent decrease was for CD4+ T cells (72-74%), which suggests that a reduction of T cells in the psoriatic plaque might not be a guarantee for positive clinical outcomes. Remarkably, the number of epidermal CD94+ NK-T cells correlated fairly well with the lack of clinical efficacy, supposing a pathogenic role for these cells in psoriasis. Further studies are needed to clarify the ambiguous role of conventional pathogenic T cells in plaque psoriasis.     

银屑病患者皮损和外周血中CD8α+α+ T细胞的研究

目的 观察银屑病患者皮损和外周血中CD8α+α+ T细胞的分布和比例,探讨其在银屑病发病中的作用。 方法 采用免疫荧光技术观察5例进展期寻常性银屑病患者和5例健康人皮肤中CD8α+α+ T细胞的分布,流式细胞仪分别检测10例进展期寻常性银屑病患者和8例健康人外周血中CD8α+α+ T细胞比例及干扰素γ（IFN-γ）和肿瘤坏死因子α（TNF-α）的表达。采用Graphpad Prism统计软件对实验组和对照组各数据进行t检验。 结果 在5例银屑病患者皮损真皮浅层均可见以CD8α+α+ T细胞为主的浸润,未见明显的CD8α+β+ T细胞浸润;而5例健康人皮肤中均未见CD8α+α+ T细胞和CD8α+β+ T细胞浸润。流式细胞仪检测,8例健康人外周血中CD8α+α+ T细胞比例为9.12% ± 4.80%,10例银屑病患者组为26.47% ± 12.99%,银屑病患者组明显高于对照组,两组比较,t = 3.96,P ＜ 0.001。在银屑病患者外周血CD8α+α+ T细胞中分泌IFN-γ和TNF-α的细胞比例分别为47.36% ± 19.38%和54.14% ± 21.14%,健康对照组分别为13.44% ± 9.21%和34.03% ± 17.22%,两组差异均有统计学意义（t值分别为4.54和2.17,P值分别 ＜ 0.001和 ＜ 0.05）。 结论 银屑病患者皮损和外周血中存在CD8α+α+ T细胞的分布和比例增多,CD8α+α+ T细胞可能是参与银屑病发病的主要CD8+ T细胞亚群。     

Enkephalin-like immunoreactivity in human skin is found selectively in a fraction of CD68 – positive dermal cells: increase in enkephalin-positive cells in lesional psoriasis

Opioid peptides are synthesized in neurons, endocrine cells, monocytes/macrophages and B and T lymphocytes. They interact with opioid receptors located on immune cells and nociceptive nerve terminals. Because opioid peptides might be of importance in inflammatory skin diseases, for example psoriasis, sections of skin from psoriatic patients were immunohistochemically stained with antisera against methionine and leucine enkephalin, CD68 (KP1, PG-M1), calprotectin (M747), M130 (Ber-MAC3), CD1a and CD3. Enkephalin-like activity was detected selectively in dermal CD68-positive macrophages/monocytes. The activity showed no association with the activation markers M747 and Ber-MAC3. There was a statistically significant increase in enkephalin-positive cells in involved psoriatic skin compared with uninvolved and normal skin. These results were confirmed by radioimmunoassay which showed elevated levels in extracts from involved psoriatic skin compared with uninvolved skin (81%) and normal skin (204%). Furthermore, preproenkephalin mRNA of an expected size was detected in involved psoriatic skin. If the increased levels of enkephalins present in monocytes/macrophages in psoriatic skin lesions reach the threshold for biological activity, they may play a role in the regulation of the inflammatory processes seen in this skin disease. Received: 3 April 1996     

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.     

银屑病外周血CD4+CD25+Foxp3+调节性T细胞的表达

目的: 检测CD4+CD25+Foxp3+调节性T细胞在不同类型银屑病患者中的表达.方法: 应用流式细胞仪检测外周血中CD4+CD25+Foxp3+调节性T细胞的表达.结果: 红皮病型银屑病患者外周血中CD4+CD25+Foxp3+调节性T细胞明显高于其他类型银屑病和正常对照组(P<0.05);斑块状银屑病CD4+CD25+Foxp3+T细胞比例高于点滴状患者(P<0.05);脓疱型银屑病患者中脓疱存在患者调节性T细胞比例明显低于脓疱消退患者(P<0.05).结论: CD4+CD25+Foxp3+调节性T细胞通过抑制效应T细胞在银屑病的病情活动中可能发挥重要作用.     

Persistent CMV infection correlates with disease activity and dominates the phenotype of peripheral CD8+ T cells in psoriasis

Background: Previously, we have reported a frequent association of active plaque psoriasis with inflammation‐mediated cytomegalovirus (CMV) reactivation. Objectives: This study aimed at characterizing the impact of CMV infection on psoriasis disease activity and peripheral cellular adaptive immune response. Patients/Methods: Twenty nine patients with active plaque psoriasis and 29 healthy controls were analysed for CMV‐serostatus, CMV‐antigenaemia, frequencies of peripheral CMV‐specific T cells and the immunophenotype of peripheral CD8+ T cells. Results: (i) Psoriasis severity was higher in CMV‐seropositive patients and positively correlated to the severity of CMV‐antigenaemia. (ii) In comparison to CMV‐seropositive healthy controls, CMV‐seropositive psoriasis patients showed a reduced frequency of circulating CMV‐specific T cells that increased under effective antipsoriatic therapy. (iii) The immunophenotype of peripheral CD8+ T cells was dominated by CMV‐seroprevalence. (iv) Selective analysis of CMV‐seronegative psoriasis patients revealed a strong expansion of a – probably early activated – CD8+ T‐cell population with the yet undescribed differentiation phenotype ‘CD45RA‐dim/CD11a‐dim’. Under effective antipsoriatic therapy this population decreased in parallel to an increase of effector differentiated CD8+ T cells. Conclusions: Taken together with our previous results of inflammation‐mediated CMV reactivation in psoriasis, our data support the concept of an interactive relationship between psoriasis and CMV infection which may be mediated by peripheral CD8+ T cells.     

银屑病和白癜风患者外周血CD4+CD25+调节性T细胞的检测

目的: 检测CD4+CD25+调节性T细胞(Treg)在白癜风和银屑病患者外周血中的表达.方法: 用流式细胞术检测19例白癜风患者、18例银屑病患者及19名正常人外周血中CD4+CD25+Treg的表达水平.结果: 白癜风患者的CD4+CD25+Treg表达率为(1.056±0.662)%,低于正常对照组(2.022±0.98)%,差异有统计学意义(P＜0.05);银屑病患者的CD4+CD25+Treg为(1.761±1.396)%,与正常人无显著性差异(P＝0.177).结论: CD4+CD25+Treg细胞在白癜风患者外周血中数量明显减少.