Immunohistochemical analysis of sensory nerves and neuropeptides,and their contacts with mast cells in developing and mature psoriatic lesions

The distribution of the neuropeptides substance P (SP), vasoactive intestinal polypeptide (VIP) and calcitonin gene related peptide (CGRP) was studied immunohistochemically in psoriatic skin during the Koebner response (6 h, 2 days, 7 days, 14 days, 21 days), and in mature psoriatic plaques, of 37 psoriatic patients. The morphological association of sensory nerves, SP and VIP with papillary mast cells was also monitored. The nerves containing SP, VIP or CGRP were very scanty in control skin, and in non-lesional and Koebner-negative psoriatic skin. The first psoriatic lesions were seen 7 days after tape stripping the symptomless psoriatic skin. SP- and VIP-containing nerves were slightly increased in Koebner-positive specimens, but the increase was very prominent in dermal papillae of mature psoriatic plaques. In the plaques, nerve-mast cell contacts were significantly increased (p<0.001) compared with non-lesional psoriatic skin. Only SP-positive fibres were detected in the epidermis and in contact with papillary mast cells. VIP was mainly located around capillaries where SP was also found. No change was noted in CGRP-positive fibres between lesional and non-lesional specimens. The appearance of SP and VIP in the capillary walls is morphological evidence for their function as vasodilators in psoriatic lesion. A slight increase in SP- and VIP-positive fibres in Koebner-positive specimens suggests that these neuropeptides may participate in the inflammatory reaction at an early stage. Their prominence in mature psoriatic plaques in turn indicates a role for them in the maintenance of psoriatic lesions. Morphological contacts between mast cells and SP-containing nerves give further evidence to the view that SP is capable of amplifying the inflammatory reaction also through the axon-reflex mechanism.Part of this work was presented at the meeting of the European Society for Dermatological Research, London, UK, 4–7 April 1992     

蕈样肉芽肿与扁平苔藓、银屑病浸润细胞的免疫组化比较

目的 探讨免疫表型对蕈样肉芽肿与扁平苔藓、银屑病鉴别诊断的意义.方法 应用ABC免疫组化技术检测15例蕈样肉芽肿,17例银屑病和17例扁平苔藓,6例正常人皮肤的CD1a、CD4、CD8、ICAM-1、LFA-1、HLA-DR(树枝状细胞)、CD30和CD7的表达情况.结果 蕈样肉芽肿表皮CD1a,CD30,ICAM-1(单一核细胞P<0.001,树枝状细胞P<0.01)的阳性细胞密度明显高于扁平苔藓、银屑病、正常人皮肤.蕈样肉芽肿表皮CD4,CD8,HLA-DR的阳性细胞密度明显高于扁平苔藓.蕈样肉芽肿真皮中CD1a阳性细胞的线性密度(P<0.01),真皮内ICAM-1和LFA-1阳性细胞百分比亦较扁平苔藓增多(P<0.05).蕈样肉芽肿表皮CD7阳性细胞与扁平苔藓、银屑病比较差异无统计学意义.银屑病和扁平苔鲜真皮内CD7阳性细胞百分比高于蕈样肉芽肿和正常人皮肤.结论 蕈样肉芽肿和扁平苔藓、银屑病皮损CD1a、CD4、CD8、ICAM-1、LFA-1、HLA-DR、CD30和CD7免疫表型有差异,其结果可为探讨发病机制提供线索.     

Functional studies of skin mast cells in lichen planus

In order to identify possible functional differences between mast cells obtained from the skin of lichen planus (LP) patients and healthy donors, biopsies from lesional skin of 11 lichen planus patients and from normal skin of 7 healthy donors were sampled. Mast cells were obtained from the skin using an enzymatic dispersion technique. The cells were challenged in vitro with substance P (SP), tumor necrosis factor α (TNF-α) and anti-IgE. Their reactivity was estimated on the basis of histamine release. LP skin mast cells and healthy skin mast cells showed similar sensitivity to stimulation with TNF-α at a concentration of 10 ^–7 M (15.2% histamine release, as a proportion of total cellular content vs 15.9%) and to stimulation with anti-IgE at a dilution of 1:100) (38.8% vs 37.0%). Spontaneous histamine release was also very similar in both the populations of mast cells (10.2% vs 12.7%, respectively). However, LP skin mast cells showed significantly higher ( P < 0.01) sensitivity towards stimulation with SP at a concentration of 10 ^–4 M than healthy skin mast cells (15.9% histamine release vs 7.0%). This finding could suggest that neurogenic inflammatory mechanisms contribute to the pathogenesis of LP. Received: 3 July 1996     

血管内皮生长因子在扁平苔藓及银屑病皮损中的表达

目的探讨扁平苔藓及银屑病患者皮损表皮血管内皮生长因子(VEGF)表达情况。方法用抗VEGF及CD34抗体行免疫组化染色,对扁平苔藓及银屑病皮损标本进行观察,计数表皮下方真皮的毛细血管密度。结果正常人表皮VEGF基本阴性,扁平苔藓及银屑病患者非病变部VEGF阴性,移行部表皮上层VEGF染色逐渐由弱到强,由间断到连续;病变部表皮VEGF阳性,以表皮上层细胞质的细颗粒状染色为主。CD34染色各部分真皮上层毛细血管密度为;扁平苔藓的非病变部(45.61±15.70)个/mm²、移行部(68.63±15.36)个/mm²、病变部(92.07±16.84)个/mm²;银屑病的非病变部(43.73±14.55)个/mm²、移行部(72.12±18.81)个/mm²、病变部(100.29±21.93)个/mm²,各病种三个部位之间比较差异均有统计学意义。结论扁平苔藓及银屑病皮损表皮分泌VEGF,并与真皮毛细血管增生扩张密切相关。     

银屑病患者的心理压力、神经内分泌系统与肥大细胞研究现状

银屑病中有相当比例的患者因心理压力而使病情恶化,但其机制尚不明确.心理压力能激活下丘脑-垂体-肾上腺轴和皮肤感觉神经,导致内分泌激素和神经介质释放.多种激素和神经介质能活化肥大细胞产生和释放一系列的炎症介质和细胞因子.银屑病患者中,一些激素、神经肽、感觉神经纤维和肥大细胞在表达水平和数量上增高.心理压力影响银屑病病情的机制之一可能与应激介质通过肥大细胞的作用有关.     

扁平苔藓皮损中肥大细胞数和P物质的表达及其意义

目的:探讨肥大细胞和P物质在扁平苔藓发病中的作用。方法:采用组织化学和免疫组化的染色方法,检测扁平苔藓皮损中未脱颗粒的肥大细胞数和P物质的表达情况。结果:甲苯胺蓝特殊染色发现,扁平苔藓皮损中未脱颗粒的肥大细胞数(3.56±1.52)明显低于正常对照组(5.22±1.28),其差异具有统计学意义(P<0.01);免疫组化染色发现,扁平苔藓皮损中P物质的表达强度明显高于正常对照组,其差异具有统计学意义(P<0.01);采用Spearman等级相关分析,二者呈一定的负相关(rs=-0.397,P<0.05)。结论:肥大细胞和P物质在扁平苔藓的发病中可能起一定的作用。     

Assessment of depression in subjects with psoriasis vulgaris and lichen planus

AIM: The aim of this study was to investigate the frequency of depressive symptoms in psoriasis vulgaris and lichen planus and to evaluate the relationship between the Beck depression scores and the Psoriasis Area and Severity Index (PASI) scores of subjects with psoriasis vulgaris. SUBJECTS: The study involved 120 subjects attending the dermatology clinic of Izmir Ataturk Training Hospital (Izmir, Turkey) and comprised 50 subjects with psoriasis vulgaris, 30 with lichen planus and 40 healthy control subjects. RESULTS: Subjects with psoriasis vulgaris, lichen planus and controls had depression scores of 58%, 53% and 20%, respectively. The Beck depression scores of patients with psoriasis vulgaris were significantly higher than those of the control group. The PASI scores showed a correlation with Beck depression scores. Smoking and drinking were very common in subjects with psoriasis vulgaris. There was no correlation between the duration of illness and depressive symptoms. CONCLUSIONS: This study confirms the importance of depressive symptoms in two common dermatological diseases. It is important to recognize this association as it affects both clinical outlook and response to treatment.     

The presence of tryptase-positive and bikunin-negative mast cells in psoriatic skin lesions

Human mast cells are well known to produce a serine protease, tryptase, which appears to play a pathogenic role in various skin inflammations. It was previously reported that a rat homologue of bikunin may inhibit tryptase activity. Various type of cells (i.e. keratinocytes) are able to produce this protein inhibitor, it still remains unclear if bikunin is present in dermal inflammatory milieu, in which mast cells, through secretion of tryptase, play an inflammatory role. Therefore, the purpose of the present study was to exploit expression and production of bikunin in dermis and dermal constituents. We first compared the dermal mast cells in psoriatic lesions with those in lesional skin of atopic dermatitis or of chronic eczema by use of immunoelectron microscopy and immunohistochemical analyses using antibodies to bikunin and tryptase. Then, we tested what kinds of cytokines may regulate the de novo synthesis of bikunin. To do so, RNA was extracted from a human mastocytic cell line, HMC-1, reverse-transcribed, and semiquantitative RT-PCR was performed using primers specific for bikunin. With immunoelectron microscopy, bikunin was found to localize on the cell membrane, while tryptase was in the secretary granules of the mast cells. In psoriatic lesions, around 70% of dermal mast cells were positive for both tryptase and bikunin, and the remaining was mostly positive for tryptase, but the expression of bikunin was under the detection limit of the experimental setting. This observation was seen in only psoriatic lesions, even in almost cured lesions, while in atopic dermatitis or chronic eczema only mast cells doubly positive for bikuin and tryptase were seen. In HMC-1, bikunin was constitutively expressed at an mRNA level, which was upregulated by stimulation with interleukine-4, but was suppressed by interferon-γ. Bearing in mind the concept that in psoriasis local cytokine milieu is shifted toward a Th1 pattern (predominant secretion of interferon-γ), tryptase-positive, bikunin-negative mast cells may be induced.     

Quantitative enzyme-histochemical analysis of tryptase- and chymase-containing mast cells in psoriatic skin

Summary Tryptase-containing mast cells have recently been found to be increased in the upper dermis of psoriatic lesions. In the present study, the distribution of chymaseand tryptase-containing mast cells was morphometrically analysed at different dermal levels of lesional and non-lesional psoriatic skin (12 patients) as well as normal human skin. Mast cell tryptase was identified enzyme-histochemically, using Z-Gly-Pro-Arg-MNA as the substrate. For demonstrating mast cell chymase, a simple and specific enzyme-histochemical staining method was developed, using Suc-Val-Pro-Phe-MNA as the substrate. All mast cells positive for chymase were also positive for tryptase and Giemsa stain. Although the number of tryptase-positive mast cells was slightly increased throughout the dermis of lesional psoriatic skin, this increase was most pronounced in the upper dermis immediately beneath, and in close contact with, the epidermis. In contrast, the number of chymase-positive mast cells was clearly decreased in the upper dermis of psoriatic lesions, but not in the deeper dermis, as compared with non-lesional psoriatic skin. In addition, all chymase-positive mast cells observed in the upper dermis were very weakly stained when compared with those in the deeper dermis. No differences were found between non-lesional psoriatic skin and normal skin in which the number of mast cells containing chymase was 72–73% of the number containing tryptase. The present results suggest that T mast cells particularly, containing tryptase but no chymase, proliferate in psoriatic lesions, and that the increase in tryptase activity and the decrease in chymase activitiy in the upper dermis may lead to an imbalance in the biochemical regulatory systems.     

T cells reactive with the NC16A domain of BP180 are present in vulval lichen sclerosus and lichen planus

Background Lichen sclerosus (LS) is a chronic inflammatory skin condition. The recent demonstration of circulating autoantibodies to extracellular matrix protein 1 and to basement membrane zone (BMZ) components, chiefly BP180, suggests that autoimmunity to these components might contribute to pathogenesis. However, there is no binding of autoantibodies in vivo and as LS is characterized by a lymphocytic infiltrate, it seems likely that LS is mediated, in part, by antigen‐specific lymphocytes. Similar mechanisms may apply to vulval lichen planus (LP), an interface dermatitis, with clinical and immunological overlap with LS. Objectives This study aims to test the hypothesis that T cells reactive with the NC16A domain of BP180 are present in the peripheral blood of patients with vulval LS and LP. Methods Isolated peripheral blood mononuclear cells from 14 patients with vulval LS, 5 with vulval LP and 4 healthy controls were grown in vitro. We examined for immunogenicity of overlapping peptides spanning the NC16A domain of BP180 using interferon‐γ enzyme‐linked immunospot assay (ELIspot) on the cultured T‐cell lines. BMZ antibodies were assayed, HLA type determined and clinical parameters noted. Results Significant interferon‐γ production was observed in response to the NC16A peptides in 6 of the 14 vulval LS and 2 of the 5 LP patients, but not in the control subjects. There was an associated autoantibody response to BP180 in 3 LS and 1 LP patient with T‐cell responses. These data suggest that in some vulval LS and LP patients, NC16A domain‐specific T cells circulate at sufficiently high frequency to be detectable in vitro and show rapid effector function. There was no association with HLA type or clinical parameters. Conclusion We have demonstrated that in > 40% of our vulval LS and LP patients, the NC16A domain of BP180 is a target for circulating T cells, and in vulval LS and LP there are associated autoantibodies to BP180.     

Immunoperoxidase and enzyme-histochemical demonstration of human skin tryptase in cutaneous mast cells in normal and mastocytoma skin

Summary Trypsin-like proteinase isolated from human skin was localized in cutaneous mast cells using immunoperoxidase and enzyme-histochemical techniques. Skin biopsy specimens were taken from four mastocytoma and four healthy patients. Immunoperoxidase staining was performed with protein A-sepharose purified rabbit polyclonal antibody raised against human skin tryptase and using aminoethylcarbazole as chromogen. The positively stained cells in the dermis were granular in character. Using peptide 4-methoxy-2-naphthylamide substrates (Bz-Arg-MNA, Z-Lys-Arg-MNA, Z-Gly-Arg-MNA, Z-Pro-Arg-MNA and Z-Gly-Pro-Arg-MNA) and Fast Garnet GBC as chromogen the red azo dye was found to precipitate in the cytoplasmic granules of the cutaneous mast cells. The enzymatic reaction was totally inhibited by diisopropyl fluorophosphate, leupeptin, and benzemidine. No marked inhibition was seen with soybean trypsin inhibitor and alpha-1-antitrypsin. The best substrate was Z-Gly-Pro-Arg-MNA giving the strongest red azo dye when incubation time was 15,30 or 60 min. These results show the localization of human skin tryptase in dermal mast cells and the usefullnes of Z-Gly-Pro-Arg-MNA as a suitable substrate tested for enzyme-histochemical localization of mast cells in healthy or mastocytoma skin.     

Lichen planus remission is associated with a decrease of human herpes virus type 7 protein expression in plasmacytoid dendritic cells

The cause of lichen planus is still unknown. Previously we showed human herpes virus 7 (HHV-7) DNA and proteins in lesional lichen planus skin, and significantly less in non-lesional lichen planus, psoriasis or healthy skin. Remarkably, lesional lichen planus skin was infiltrated with plasmacytoid dendritic cells. If HHV-7 is associated with lichen planus, then HHV-7 replication would reduce upon lichen planus remission. HHV-7 DNA detection was performed by nested PCR and HHV-7 protein by immunohistochemistry on lesional skin biopsies from lichen planus patients before treatment and after remission. Biopsies were obtained from lichen planus lesions before treatment (n = 18 patients) and after remission (n = 13). Before treatment 61% biopsies contained HHV-7 DNA versus 8% after remission (P = 0.01). HHV-7-protein positive cell numbers diminished significantly after remission in both dermis and epidermis. Expression of HHV-7 was mainly detected in BDCA-2 positive plasmacytoid dendritic cells rather than CD-3 positive lymphocytes. HHV-7 replicates in plasmacytoid dendritic cells in lesional lichen planus skin and diminishes after remission. This study further supports our hypothesis that HHV-7 is associated with lichen planus pathogenesis.     

Use of proliferation rate, p53 staining and perforating elastic fibers in distinguishing keratoacanthoma from hypertrophic lichen planus: a pilot study

Background: Distinguishing keratoacanthoma (KA) and hypertrophic lichen planus (LP) histopathologically can be difficult, and the challenge is compounded by the tendency of KA to arise in association with hypertrophic LP. Methods: In this pilot study, we compared 18 cases each of KA and hypertrophic LP for proliferation index (MIB‐1), p53 staining and the presence of perforating elastic fibers (elastic Verhoeff‐van Gieson) to determine the utility of these staining modalities in distinguishing KA from hypertrophic LP. Results: Proliferation index in KA compared to hypertrophic LP is 88.2 (mean positive MIB‐1 cells/×100 field), SD = 56.6 and 47.3, SD = 68.4, respectively. p53 staining in KA compared to hypertrophic LP is 251 (mean positive cells/×100 field), SD = 117 and 158, SD = 119, respectively. Fifteen of eighteen (83%) keratoacanthomata demonstrate perforating elastic fibers compared to 1/18 (6%) for hypertrophic LP. Conclusion: Proliferation index is not significantly different between KA and hypertrophic LP (p = 0.059). Expression of p53 is increased in KA over hypertrophic LP (p = 0.024). The presence of perforating elastic fibers in KA is significantly different from hypertrophic LP (p < 0.0001) and suggests that elastic Verhoeff‐van Gieson staining may be of practical benefit in distinguishing KA from hypertrophic LP in difficult cases. Bowen AR, Burt L, Boucher K, Tristani‐Firouzi P, Florell SR. Use of proliferation rate, p53 staining and perforating elastic fibers in the distinction of keratoacanthoma and hypertrophic lichen planus: a pilot study.     

Reappraisal of in situ immunophenotypic analysis of psoriasis skin: interaction of activated HLA-DR+ immunocompetent cells and endothelial cells is a major feature of psoriatic lesions

Psoriasis is an inflammatory skin disease of unknown aetiology. Many observations indicate that T cells play an important role in the pathogenesis of the disease. Upregulation of MHC class-II molecules on immunocompetent cells, endothelial cells and keratinocytes on lesional psoriatic skin has been regarded as a hallmark of the disease. However, there is some controversy in the literature regarding the cell types expressing class-II molecules and there is limited information about the presence of immune cells other than T cells and antigen presenting cells in the cellular infiltrates of psoriatic skin. We therefore reinvestigated the subject using immunocytochemical single and multiple staining techniques. In agreement with earlier reports, our studies showed that the cellular infiltrates in lesional skin consist largely of HLA-DR⁺/IL-2R⁺ T cells, HLA-DR⁺/CD1a⁺ Langerhans cells, and HLA-DR⁺/CD68⁺ macrophages. We found increased HLA-DR expression mostly on immunocompetent cells and endothelial cells, but no prominent HLA-DR expression on keratinocytes in lesional psoriatic skin. Upregulation of HLA-DR on endothelial cells and in mononuclear infiltrates was also evident in the non-lesional skin of psoriatic patients as compared with normal controls. B cells and natural killer cells were also found in the cellular infiltrates in lesional psoriatic skin. In spite of the presence of a large amount of activated T cells in the epidermis, we found that HLA-DR expression on keratinocytes was not a major feature of psoriatic skin.     

Effects of FK506 and Cyclosporin a on proliferation,histamine release and phenotype of murine mast cells

Using mouse peritoneal cavity mast cells, we investigated the effects of FK506 and cyclosporin A (CsA) on cell proliferation and histamine release induced by anti-IgE antibody, calcium ionophore (A23 187), or neuropeptide (substance P). Both FK506 and CsA inhibited cytokine-dependent mast cell proliferation in a dose-dependent manner. The inhibitory effects of these compounds on mast cell proliferation was reversible; the removal of the chemicals from the incubation medium resulted in the reinitiation of mast cell proliferation. Flow cytometric analysis suggested that the inhibitory effect of FK506 and CsA was mostly due to G ₁ /S boundary block, although a significant number of G ₂ -arrested cells were also observed following FK506 treatment. Both FK506- and CsA-treated mast cells showed a similar inhibition of histamine release induced by A23187. However, CsA at higher concentrations inhibited the histamine release induced by anti-IgE antibody or substance P more markedly than FK506. Cellular histamine content was decreased by CsA treatment while FK506 had no effect. The staining properties of peritoneal mast cells changed from connective tissue-type mast cell-like to mucosal mast cell-like during CsA treatment but not during FK506 treatment. Thus FK506 and CsA have different effects on mast cell proliferation as well as histamine release, that might be associated with a phenotypic change of the cells during culture. Received: 28 February 1995     

A study of the pathogenesis of Rosacea: how angiogenesis and mast cells may participate in a complex multifactorial process

In the present study we evaluated, in involved and clinically uninvolved skin of Rosacea, microvessels density (MVD) and total vascular area (TVA) in addition to multiple morphologic characteristics of microvessels and also mast cells (MCs) number. We examined also the relationship between angiogenesis, MCs number and disease clinicopathological data. The study included 69 patients with Rosacea. A skin biopsy with a 4-mm punch was performed from clinically involved skin in each case. In nine randomly selected patients, facial biopsy specimens were obtained from both involved and clinically uninvolved skin. Histological sections, immunostained for factor VIII, were evaluated by image analysis for the quantification of MVD, TVA and several morphometric parameters related to the vessel size or shape. MCs detection in the dermis was carried out using the chloracetate esterase method (Fast Blue RR) in parafin sections. Serum antibodies against H.pylori were detected. Statistically important differences concerning the factors of angiogenesis between lesional and clinically non-lesional skin were demonstrated. A statistical important correlation was found also between high vascular density, PPR clinical type and the presence of ocular manifestations. MVD or TVA showed no correlation with the degree of solar elastosis or inflammation and with the Demodex density as well. However, high MVD values were found to correlate with granuloma formation in the dermis. MCs number were significantly greater in lesional compared to clinically non-lesional skin. Statistical significance was shown between MCs density and disease duration. However, no correlation between MCs number and blood vessel density was found. Angiogenesis seems to play an important role in the pathogenesis especially of the more severe clinical form of Rosacea. MCs seem to participate in evolution to disease chronicity by contributing to inflammation, angiogenesis and tissue fibrosis.     

Quantitative studies on nonlymphoid mononuclear cell subpopulations in cutaneous infiltrates. I. Stage-related changes of dendritic nonlymphoid mononuclear cells, Langerhans' cells, and macrophages in lichen planus lesions

In previous investigations on lichen planus, we suggested that in early lesions T4-positive cells might be antigen-specifically driven, whereas in late lesions T8-positive cells may be cytotoxic to keratinocytes. To verify this hypothesis, we investigated the following nonlymphoid mononuclear cell subpopulations in early versus late lichen planus lesions: interdigitating cells (phenotype: S100-positive, lysozyme-negative, T6-negative, M3-negative), Langerhans cells (phenotype: S100-positive, lysozyme-negative, T6-positive, M3-negative), macrophages (phenotype: S100-negative, lysozyme-positive, T6-negative, M3-positive). Interdigitating cells were moreover identified in semithin and ultrathin sections by distinctive morphological characteristics. The S100-positive/lysozyme-positive cell ratio was higher (p less than 0.01) in early lesions than late lesions. In dermis but not in epidermis (NS), of early lesions, T6-positive cells were less represented than S100 positive cells (p less than 0.025). Thus, Langerhans' cells largely predominated over interdigitating cells in epidermis, but the two populations were both represented in dermis. Lysozyme-positive and M3-positive cells, more abundant in late lesions than in early lesions (p less than 0.001), were often filled with pigment granules.