Perforin expression in peripheral blood lymphocytes and skin-infiltrating cells in patients with lichen planus

BACKGROUND: Current evidence suggests that lichen planus is a T-cell-mediated autoimmune disease in which cytotoxic mechanisms have been poorly investigated. OBJECTIVES: We investigated the expression of perforin in subpopulations of peripheral blood lymphocytes (PBL) in exacerbation and remission phases of the disease as well as in skin lesions. METHODS: We performed a simultaneous detection of perforin (intracellular molecule) and cell surface antigens on PBL by flow cytometry, and skin lesions were investigated by immunohistochemistry. RESULTS: The most interesting finding was a significant increase of perforin expression in cytotoxic T lymphocytes (CD3+ perforin+ cells) in the exacerbation phase of disease (P < 0.05), which was mostly located in the CD8+ subpopulation (CD8+ perforin+) (P < 0.01). Using immunohistochemistry we confirmed the infiltration of T lymphocytes in skin lesions, especially of CD4+ and CD8+ phenotypes, compared with uninvolved (P < 0.05) and healthy skin (P < 0.01). The expression of perforin was also significantly higher in lesional skin compared with nonlesional and healthy skin (P < 0.05). CONCLUSIONS: Our results clearly show the upregulation of perforin expression in peripheral blood as well as in lesions of patients with lichen planus and therefore suggest an important role for perforin in this autoimmune disease.     

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.     

CD103+T细胞在银屑病皮损中的表达

目的：明确银屑病患者皮肤CD103+T细胞的表达及其与银屑病严重程度的关系。方法：免疫组化检测29例银屑病患者皮损和非皮损皮肤及6名健康对照皮肤中表皮及真皮CD103+T细胞的表达。计算银屑病患者PASI值。结果：CD103+T细胞主要在真皮表达。银屑病患者皮损和非皮损真皮中每个高倍视野CD103+T细胞百分率分别为（26.06%±11.72）%和（12.82±4.5）%（P<0.05）;健康人对照皮肤真皮内CD103+T细胞百分率为（7.47±1.3）%,明显低于银屑病非皮损区（P<0.05）。银屑病患者皮损中,CD103+T的表达与PASI值正相关（P<0.05）。 结论：真皮中CD103+T细胞可能与银屑病的发病及严重程度有关。     

Perforin and granzyme B may contribute to skin inflammation in atopic dermatitis and psoriasis

BACKGROUND: Infiltration of the skin by pathogenic T cells is regarded as a key factor in the development of inflammatory skin diseases such as atopic dermatitis (AD) and psoriasis. OBJECTIVES: To investigate whether T cells containing cytotoxic proteins may contribute to the generation of skin inflammation in these skin diseases. METHODS: Skin biopsy specimens were obtained from non-lesional and lesional skin of patients with chronic AD (n = 8) and psoriasis (n = 6), and from non-atopic controls with normal skin (n = 6). Expression of perforin and granzyme B was investigated by immunohistochemistry. RESULTS: A significant enhancement of perforin and granzyme B expression was observed in lesional AD skin as compared with normal skin, non-lesional AD skin and psoriasis. Expression of these cytotoxic proteins was also increased in psoriasis as compared with normal skin and non-lesional psoriatic skin. Immunoreactivity for perforin and granzyme B was mainly found in the cytoplasm of lymphocytic cells located in the perivascular infiltrate. In AD increased numbers of positive cells were also observed focally at sites of spongiosis in the epidermis. Double immunostaining revealed that both CD4+ and CD8+ T cells are capable of expressing perforin and granzyme B. CONCLUSIONS: Our data suggest that cytotoxic CD4+ and CD8+ T cells containing perforin and granzyme B may play an integral part in eliciting cutaneous inflammation in AD.     

银屑病患者角质形成细胞对朗格汉斯细胞免疫刺激功能的影响

为探讨银屑病患者皮损处角质形成细胞对朗格汉斯细胞（LCs）免疫刺激功能的影响，从健康者外周血分离单核细胞，经IL－4＋GM－CSF＋TGF－β1培养5天后分化发育为1Cs,再加入银屑病患者角质形成细胞培养上清继续培养2天，然后通过Leica显微镜观察其形态；通过混合淋巴细胞反应分析其种T的刺激功能。结果显示，以健康人角质形成细胞上清为对照，LCs经银屑病患者角质形成细胞上清培养2天后，拥有不规则突起的细胞明显较正常组增多。同时，其刺激T淋巴细胞增殖的能力也增强。结果表明，银屑病患者角质形成细胞上清培养的LCs表现出较强的免疫刺激功能，并在银屑病相关的免疫反应过程中发挥了重要作用，提示这可能与银屑病患者角质形成细胞表达的某些因子有关。     

Skewed distribution of natural killer cells in psoriasis skin lesions

Psoriasis is a hyper‐proliferative disease of the skin in which immunological mechanisms play a direct pathogenetic role. There have been limited studies of natural killer (NK) cells in psoriasis. The aim of this study was to examine the phenotype of NK cells in skin biopsies and peripheral blood mononuclear cells from patients with psoriasis and healthy controls. CD56⁺CD16^? and CD56⁺CD16⁺ NK cells were isolated from lesional skin, unaffected skin and PBMC of psoriasis patients, and normal skin and PBMC from healthy controls. The expression of CD57, NKG2A and NKG2C was assessed by flow cytometry. NK cells in psoriasis skin lesions were skewed in their expression of CD57, a marker of NK cell maturity, with CD57 expression significantly reduced and NKG2A expression increased on NK cells in lesional and unaffected skin compared to controls. These data suggest that in this patient cohort, NK cells could be isolated from psoriasis lesions and exhibit an immature phenotype.     

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。     

Routine flow cytometric immuno-staining of T-cell perforin is preserved using diethylene glycol for erythrocyte-lysis but lost by the use of ammonium chloride

Abstract:  The system of perforin-containing lytic granules of cytotoxic lymphocytes plays an important role in the immune defense machinery. Investigating the capacity and efficacy of this system in and ex vivo is helpful to understand immune responses and their modulation by therapeutic interventions. With regard to its pathophysiological function, we recently demonstrated a substantial increase of perforin-positive CD8⁺ T cells in the peripheral blood of patients with acute exacerbated psoriasis and severe generalized drug reactions, and, in marked contrast, a highly significant perforin-depletion and a perforin-hyperreleasability in atopic dermatitis (AD). To streamline the perforin staining procedure, isolation of peripheral blood mononuclear cells (PBMC) by Ficoll density centrifugation was to be replaced by lysis of erythrocytes. Ammonium chloride lysis, however, reduced the perforin content of CD8⁺ T cells substantially (up to 75–100%) as compared with Ficoll isolation of PBMC. Incubation of cells in concanamycin A, a selective inhibitor of H⁺-ATPases, resulted in a similar loss of perforin staining pointing to the critical influence of lysosomal pH. Using diethylene glycol-mediated erythrocyte lysis, perforin was well preserved to be readily detectable by immuno flow cytometry. Representative examples of the application of this optimized perforin staining procedure as well as accumulated data are given for various dermatological disorders [psoriasis, atopic dermatitis, cutaneous drug reactions, graft-versus-host disease (GVHD)] with strong involvement of the cytotoxic T-cell population. Our findings may help to explain recent conflicting reports about a widely varying range of the portion of perforin-positive cells in healthy individuals as a reflection of such artificial methodological influences.     

Alefacept therapy reduces the effector T-cell population in lesional psoriatic epidermis

Alefacept, a LFA-3/IgG1 fusion protein, interferes with the activation and proliferation of T cells by binding to the CD2 receptor on their surfaces. The clinical efficacy of this drug has been demonstrated in chronic plaque psoriasis. We performed a single-center, open-label study to investigate the immunohistochemical effects in psoriatic lesional skin. A group of 11 patients with plaque psoriasis all received 12 weekly doses of 7.5 mg alefacept intravenously. Skin biopsies were obtained at baseline and on days 8, 43 and 92, and were evaluated by digital image analysis after immunohistochemical staining. After completion of treatment, 8 out of the 11 patients experienced a reduction in PASI of 50% or more compared to baseline. Immunohistochemical analysis displayed a gradual decrease in the number of cutaneous T cells during therapy, with a significant reduction in epidermal CD8⁺ cells and dermal CD4⁺ cells on day 92. Patients with a reduction in PASI of 50% or more after therapy had a clearance of effector/memory T cells from the epidermis, in contrast to patients with a reduction in PASI of less than 50%. These findings support the hypothesis that effector/memory T cells play a prominent role in the pathogenesis of psoriasis, and that alefacept is capable of reducing these cells in lesional psoriatic skin.     

5—羟色胺在银屑病患者皮损中的表达

目的：探讨5—羟色胺在银屑病发病机制中的作用。方法：用免疫组化SP法检测银屑病患者皮损中5—羟色胺(5—HT)的表达。结果：进行期银屑病患者皮损处棘细胞，汗腺腺细胞，皮脂腺细胞，毛囊壁细胞浆中5—HT表达呈中等以上阳性，静止期减弱。寻常型和脓疱型无明显差异，正常人皮肤为阴性。结论：5—HT可能有促进角质形成细胞过度增殖的作用，从而参与银屑病的发病。     

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。     

The development of manifest psoriatic lesions is linked with the invasion of CD8+ T cells and CD11c+ macrophages into the epidermis

Koebner response was studied in 35 psoriatic patients. Two punch biopsies per patient were taken from non-lesional psoriatic skin before, and 6 h, 2 days, 7 days, 14 days and 21 days after, tape stripping. Alterations in the numbers of CD1+ Langerhans cells, CD4+ and CD8+ T cells and CD11c+ macrophages were mapped morphometrically. Results were compared with lesional and non-lesional psoriatic skin, and control skin. Nine of 35 patients were Koebner-positive. No statistically significant differences were noted between non-lesional psoriatic and control skin. CD4+ T cells increased in number 2 days after trauma in both the epidermis and the dermis, whereas epidermal CD8+ T cells and CD11c+ macrophages increased only in the Koebner-positive lesional skin after 7 days. The changes in lesions induced by tapestripping resembled those seen in lesional psoriatic skin (mature plaques). The number of CD1+ cells increased in mature psoriatic lesions only. It seems possible that trauma per se stimulates the accumulation of CD4+ T cells at the site of injury, but the development of manifest psoriatic lesions correlates with invasion of CD8+ T cells and CD11c+ macrophages into the epidermis.     

Suprabasal expression of human amphiregulin in the epidermis of transgenic mice induces a severe, early-onset, psoriasis-like skin pathology: expression of amphiregulin in the basal epidermis is also associated with synovitis

The expression of amphiregulin (AR) in the basal epidermis of transgenic mice [keratin 14 promoter AR gene (K14-ARGE)] has been previously shown to induce an early-onset and severe skin pathology, with many similarities to psoriasis. In this study, it is demonstrated that involucrin enhancer/promoter-dependent expression of human AR (INV-AR) in the suprabasal epidermis of transgenic mice also produces a cutaneous psoriasis-like phenotype. INV-AR mice possess a limited lifespan and scaling, papillomatous, erythematous skin with partial alopecia. INV-AR mouse histopathology also revealed epidermal hyperkeratosis, parakeratosis, acanthosis, and an exaggerated dermal vasculature. A dermal and epidermal infiltrate was also evident and consisted of both neutrophils and CD3(+) T lymphocytes. The histology of synovial joints in both the INV-AR mice and the K14-ARGE mice of our previous investigation was examined. The histologic examination revealed that 3-week-old INV-AR transgenic mice displayed normal knee joint histology, while 2- to 3-week-old K14-ARGE transgenic mice frequently displayed synovitis, as exemplified by the presence of a mixed leukocytic infiltration, increased vascularization, and enhanced deposition of fibrous matrix in the knee synovium. These results demonstrate that AR overexpression in both the basal and suprabasal epidermis of transgenic mice induces a phenotype that mimics cutaneous psoriasis, while basal AR expression is also associated with synovial inflammation, a precursor to the psoriasis-associated arthropathy, psoriatic arthritis. Collectively, the results implicate epidermal AR expression as a possible mediator of innate cutaneous immunity and epidermal proliferation and also as a potential trigger of both cutaneous psoriasis and psoriatic arthritis.     

Increased production of transforming growth factor-alpha in psoriatic epidermis

To elucidate the involvement of transforming growth factor-alpha (TGF-alpha) in the pathogenesis of psoriasis, we measured TGF-alpha levels in the extracts from six normal epidermis and four psoriatic involved epidermis samples by enzyme-linked sorbent assay using monoclonal antibody specific for TGF-alpha. The amount of TGF-alpha in the extracts of normal epidermis was 1.45 +/- 1.06 ng/g of wet tissue, while the amount in psoriatic involved epidermis was 6.71 +/- 0.75 ng/g of wet tissue. The TGF-alpha level in psoriatic involved epidermis was thus 4.62 fold higher than that of normal epidermis (P less than 0.001). TGF-alpha binds to epidermal growth factor receptors and functions as an autocrine growth factor for epidermal keratinocytes. Therefore, the increased levels of TGF-alpha may be involved in the induction or the maintenance of hyperproliferation of psoriatic epidermal keratinocytes.     

银屑病皮损中c-myc和c-jun的检测

目的:为了探索c-myc及c-jun与银屑病的关系。方法:运用免疫组化SP法对22例寻常型银屑病患者及15例正常人皮肤c-myc及c-jun的表达进行观察。结果:c-myc、c-jun在银屑病皮损中过度表达,而在正常皮肤不表达或弱表达,结论:c-myc、c-jun可能与银屑病的表皮细胞过度增殖、分化异常有关。     

Functional characterization of CD4+CD25+ regulatory T cells differentiated in vitro from bone marrow-derived haematopoietic cells of psoriasis patients with a family history of the disorder

BACKGROUND: In psoriasis CD4+CD25+ regulatory T cells are functionally deficient. The imbalance between regulatory and effector T-cell functions is important for inducing psoriasis. It is reasonable to speculate that the dysfunctional activity of CD4+CD25+ regulatory cells may originate partly from the abnormal haematopoietic cells determined mainly by genetic background. OBJECTIVES: To test the hypothesis that haematopoietic stem cells are responsible for dysfunctional CD4+CD25+ regulatory cells in psoriasis. METHODS: Bone marrow-derived CD34+ haematopoietic cells from patients with psoriasis (with a family history of psoriasis) and from normal controls were differentiated into T cells in vitro. CD4+CD25+ T cells were isolated by an immunomagnetic bead method, and proliferation activity and capacity for cytokine secretion were determined. Furthermore, the ability of CD4+CD25+ T cells to suppress the proliferative responses of allogeneous peripheral blood CD4+CD25- effector T cells was assessed in vitro. RESULTS: The differentiated CD4+CD25+ T cells of psoriatic origin showed similar characteristics to those of normal volunteers, including proliferation activity and secretion profile of the cytokines interleukin (IL)-2, IL-4, IL-8, IL-10 and interferon (IFN)-gamma. However, proliferation and secretion levels of the cytokines IL-2 and IL-10 for CD4+CD25+ cells of psoriatic CD34+ cell origin were significantly lower than those of normal controls in response to streptococcal superantigen (Strep-A). In particular, CD4+CD25+ T cells differentiated from psoriatic CD34+ cells were functionally insufficient to restrain effector T-cell proliferation. CONCLUSIONS: CD4+CD25+ T cells differentiated in vitro from haematopoietic cells of patients with psoriasis are impaired in regulatory function. The dysfunction of psoriatic CD4+CD25+ T cells may be due to inherent genetic programming passed down from bone marrow-derived haematopoietic cells.