Interaction of HSV-1 infected peripheral blood mononuclear cells with cultured dermal microvascular endothelial cells: a potential model for the pathogenesis of HSV-1 induced erythema multiforme

The effect of herpes virus infection on human dermal microvascular endothelial cells and herpes-virus-1-infected peripheral blood mononuclear cells on human dermal microvascular endothelial cells was studied as a model of herpes-associated erythema multiforme. After infection of human dermal microvascular endothelial cells with native herpes virus and overnight culture, 60%--90% of human dermal microvascular endothelial cells showed cytopathic effects. HLA class I molecules and CD31 (PECAM-1) surface expression in herpes-virus-infected endothelial cells were substantially downregulated, whereas CD54 (ICAM-1) remained unchanged. Cocultivation with herpes-virus-1-infected peripheral blood mononuclear cells left characteristic plaques on the human dermal microvascular endothelial cell monolayer; however, very few human dermal microvascular endothelial cells (1%--3%) were infected. Adhesion molecule expression of human dermal microvascular endothelial cells cocultivated with herpes-virus-infected peripheral blood mononuclear cells demonstrated a 5-fold increase in CD54 expression, a 2-fold increase in HLA class I expression, but no change of CD31 by fluorescence-activated cell sorter analysis. Incubation of human dermal microvascular endothelial cells with ultraviolet-C irradiated herpes-virus-infected peripheral blood mononuclear cells had no effect on morphology or adhesion molecule expression levels. Changes of adhesion molecule expression by direct infection or cocultivation with peripheral blood mononuclear cells (with native and ultraviolet-C inactivated herpes virus infection) were also documented at the mRNA level. Adhesion assays demonstrated an increased binding of herpes-virus-infected peripheral blood mononuclear cells versus noninfected peripheral blood mononuclear cells to noninfected human dermal microvascular endothelial cells. Our results suggest that incubation of herpes-virus-infected peripheral blood mononuclear cells with human dermal microvascular endothelial cells induces significant upregulation of CD54 and major histocompatibility complex class I molecules in the surrounding noninfected human dermal microvascular endothelial cells, which is associated with an increased binding of peripheral blood mononuclear cells. Our in vitro findings may serve as a model for herpes-associated erythema multiforme possibly explaining the dermal inflammatory reaction seen in that condition.     

Therapy of banal HSV lesions: molecular mechanisms of the antiviral activity of zinc sulfate]

Preparations of heparin in combination with the physiologically harmless and even beneficial zinc sulphate are available for the topical treatment of superficial mucocutaneous lesions caused by HSV (herpes simplex virus). We study the molecular mechanism of the antiviral effects of zinc ions. A concentration of 100 mumol/l Zn2+ in the culture medium reduces the virus yield in a HSV infected AGMK cell line to less than 1/1000 of the control. At this concentration zinc sulphate does not exert any major cytotoxic effects, nor does it block the synthesis of viral or cellular DNA. Free virus, however, is inactivated by 8 orders of magnitude by 15 mmol/l zinc sulphate within a few hours. The inactivated virus is limited in the glycoprotein-dependent functions adsorption and penetration. Electron micrographs show massive deposition of zinc onto virion components. The dramatic antiviral effect in vivo is therefore explained by an inhibition of virion glycoprotein functions after accumulation of zinc in the virion, presumably by binding to sulphhydryl groups of glycoprotein B.     

Peroxidase-mediated mechanisms are involved in the melanocytotoxic and melanogenesis-inhibiting effects of chemical agents

Melanogenesis is based on the enzymatic conversion of the amino acid tyrosine, through a series of intermediates, to melanin pigments. The nature of the enzymes involved in the different steps of melanogenesis has been intensely debated. However, it is now believed that tyrosinase is responsible for the conversion of tyrosine to dopa and of dopa to dopaquinone, and that peroxidase accomplishes the oxidative polymerization of the eventually formed indoles to eumelanin pigments. Some very few investigators have also considered a main role for peroxidase in initiating melanogenesis. At present, most different hypotheses are focused on tyrosinase-mediated mechanisms to elucidate the melanocytotoxic and depigmenting activities of chemicals. However, many properties of these agents cannot be explained by such mechanisms. Most of the melanocytotoxic agents (e.g. hydroquinone, catechols, butylated hydroxyanisole) can be converted to cytotoxic species, such as quinones, by the peroxidase-H(2)O(2) system. On the other hand, many of the melanogenesis inhibitors which are not known to inhibit tyrosinase (e.g. glucocorticoids, ascorbic acid, indomethacin) have the capacity to strongly inhibit peroxidase activity. We have proposed that peroxidase-mediated mechanisms, in addition to or in several instances rather than tyrosinase-mediated mechanisms, can explain the melanocytotoxic and depigmenting properties of such agents.     

Cutaneous effects of infrared radiation: from clinical observations to molecular response mechanisms

Human skin is exposed to infrared (IR) radiation (760 nm-1 mm) from natural as well as artificial sources that are increasingly used for cosmetic or medical purposes. Epidemiological data and clinical observations, however, indicate that IR radiation cannot be considered as totally innocuous to human skin. In particular, IR radiation, similar to ultraviolet radiation, seems to be involved in photoaging and potentially also in photocarcinogenesis. The molecular consequences resulting from IR exposure are virtually unknown. Recent studies, however, have begun to shed light on the basic molecular processes such as cellular signal transduction and gene expression triggered by exposure to IR radiation. In response to IR irradiation, mitogen-activated protein kinase signaling pathways were activated mediating the upregulation of matrix metalloproteinase-1 expression. This previously unrecognized molecular 'IR response' shows that IR radiation is capable of specifically interfering with cellular functions and provides a molecular basis for biological effects of IR on human skin.     

凝血机制参与慢性荨麻疹发病的研究进展

凝血机制与慢性荨麻疹有关.内外凝血途径均参与其发病,同时被激活产生凝血酶.凝血酶不仅可以直接作用于血管内皮细胞,增加血管通透性,还可以间接使肥大细胞脱颗粒释放组胺,从而诱发荨麻疹.慢性荨麻疹患者检测出的一些凝血标记物也间接证明凝血机制参与其发病.在慢性荨麻疹发病过程中,凝血机制与炎症反应机制、自身免疫机制和血管机制密切相关.对于抗组胺治疗无效的顽固性荨麻疹患者,抗凝血治疗提供了新的思路和方向.     

The burden of infection with HSV-1 and HSV-2 in England and Wales: implications for the changing epidemiology of genital herpes

OBJECTIVE: To measure the burden of infection with herpes simplex type 1 (HSV-1) and herpes simplex type 2 (HSV-2) in the general population of England and Wales and to assess temporal changes in the incidence of HSV-1 infection in childhood. METHODS: 4930 residual blood samples taken from people aged 0-69 years and submitted to 15 public health laboratories in England and Wales between January 1994 and June 1995, and 500 samples taken from people aged 10-14 years between November 1986 and December 1987, were screened for IgG antibody to HSV-1 and HSV-2 using type specific ELISA assays. RESULTS: The prevalence of antibody to HSV-1 in 10-14 year olds declined from 34% in samples collected in 1986-7 to 24% in samples collected in 1994-5 (p < 0.001). HSV-1 antibody prevalence in adults increased with age and was higher in females than males, reaching 54% in females aged 25-30 years in 1994-5. In samples collected in 1994-5 from people aged 16-69 years HSV-2 antibody was detected in sera from 3.3% of men and 5.1% of women. CONCLUSIONS: The incidence of HSV-1 infection in childhood is falling in England and Wales. The prevalence of HSV-2 infection in the general population is low, with the rate of infection significantly lower than that described for the general population in the United States and developing countries. The falling rate of HSV-1 infection in childhood may be one factor contributing to the increasing incidence of genital HSV-1 infection.     

Propranolol for infantile haemangiomas: insights into the molecular mechanisms of action

Infantile haemangiomas (IH) are the most common benign tumours of infancy. Although most IH are innocuous and 85–90% regress spontaneously, some may become life‐ or function‐threatening and require immediate treatment. Previous standard therapeutic options include physical measures (laser surgery, cryosurgery) and systemic corticosteroids, in severe cases also vincristine, α‐interferon or cyclophosphamide, all bearing the risk of serious side‐effects. Oral propranolol is a very recent therapeutic option for complicated IH with impressive efficacy and generally good tolerance. The effects of propranolol on IH were discovered by chance, and very little is known about its mechanisms of action in IH. Here we present a summary of current knowledge of how propranolol interferes with endothelial cells, vascular tone, angiogenesis and apoptosis. Early, intermediate and long‐term effects of propranolol on IH can be attributed to three different pharmacological targets. Early effects (brightening of the haemangioma surface within 1–3 days after start of therapy) are attributable to vasoconstriction due to decreased release of nitric oxide. Intermediate effects are due to the blocking of proangiogenic signals (vascular endothelial growth factor, basic fibroblast growth factor, matrix metalloproteinase 2/9) and result in growth arrest. Long‐term effects of propranolol are characterized by induction of apoptosis in proliferating endothelial cells, and result in tumour regression.     

分枝杆菌肉芽肿形成的细胞及分子机制究进展

分枝杆菌肉芽肿是由细菌与不同的宿主细胞如巨噬细胞、树突细胞、淋巴细胞等相互作用,在各种免疫分子如细胞因子、黏附分子、补体等参与下,形成的特征性病理学结构.其形成过程中细菌各种成分、宿主不同细胞、产生的不同免疫分子均起重要作用.而斑马鱼模型的建立及原位荧光观察方法的应用亦为分枝杆菌尤其是海鱼分枝杆菌感染肉芽肿的体内形成及演变研究提供基础.     

Sodium lauryl sulfate effect on the density of epidermal Langerhans cells.

The effect of different test models for sodium lauryl sulfate (SLS)-induced irritant contact dermatitis on epidermal Langerhans cells (LC) numbers was examined. Finn Chambers, 8 and 12 mm, containing 15 and 34 or 50 μl, respectively. of l% aq. solution of SLS were applied to human forearm skin for 48h as single or repeated application. The results showed a clear difference between the effects with the 2 chamber Sizes. The effect of the 8-mm chambers could result in increased, unchanged or decreased LC numbers, while 12-mm chambers always produced a decrease. These results seem to explain, at least partly, the discrepant results reported from various laboratories.     

Suppressive valacyclovir therapy: impact on the population spread of HSV-2 infection

OBJECTIVES: Recent trial results demonstrate that the transmission probability of HSV-2 in monogamous couples is nearly halved by the use of valacyclovir as suppressive therapy. GOAL: The goal of this study is to understand the potential impact of suppressive valacyclovir therapy on the transmission of HSV-2 within a population. STUDY DESIGN: A mathematical model of HSV-2 epidemiology was developed which included suppressive therapy with the efficacy observed in the clinical trial. The model represented HSV-2 spread in an age and sexual activity stratified population where rates of viral shedding declined based on time since infection. The model tested the impact of a range of suppression coverage levels. RESULTS: Suppressive therapy reduces the population incidence of HSV-2. With coverage rates of 3.2%, the incidence of HSV-2 would be reduced by between 1.8% and 2.8%. Higher coverage rates were estimated to reduce the incidence of new cases up to 13%. Starting suppression closer to the time of infection also reduces the incidence of new cases. CONCLUSION: The impact of suppressive therapy on the HSV-2 epidemic is modest at current coverage levels but could be substantially increased with higher rates of diagnosis and a focus on coverage soon after infection.     

Caveolin-1 is expressed on multipotent cells of hair follicles and might be involved in their resistance to chemotherapy

BACKGROUND: Caveolin-1 is the principal protein that composes caveolae, which are vesicular invaginations present on the plasma membrane of different cell types. Caveolae are involved in a variety of cellular functions including regulation of proliferation rate and resistance to chemotherapeutic drugs. Chemotherapy frequently induces alopecia which is reversible most probably due to the low proliferative rate of hair follicle stem cells and due to the expression of proteins which confer resistance. OBJECTIVES: Using a specific animal model and immunohistochemistry, we analysed the expression of both caveolin-1 and the cell proliferation marker beta-catenin, at different stages of the hair follicle cycle, both before and after doxorubicin (DXR) -induced alopecia. METHODS: Seven-week-old C57BL/6 mice were depilated in order to synchronize hair follicle cycle in the anagen phase. Chemotherapy with DXR 15 mg kg(-1) was used to induce alopecia. Control and treated mice were then sacrificed at precise time points and caveolin-1 expression in hairs at different stages of the cycle were analysed by immunohistochemistry. By double immunofluorescence, colocalization of caveolin-1 and cytokeratin-15 was confirmed in the bulge region. The state of proliferation of cells composing hair follicle was assessed by beta-catenin immunohistochemistry. RESULTS: Caveolin-1 was expressed by the cells of the bulge area, the multipotent compartment of the hair follicle, during all phases of growth (anagen), regression (catagen) and resting (telogen). During the anagen phases, nuclear beta-catenin labelling was not observed in bulge cells, but rather in the deeper portion of the follicle. Damaged hair follicles from DXR-treated mice presented bulge cells which still expressed caveolin-1, suggesting that this protein might play a role in their drug resistance. As expected, no beta-catenin nuclear staining was detectable in DXR-treated hair follicles, indicating the complete lack of proliferative processes. The differential localization of caveolin-1 and beta-catenin suggests that the mutually exclusive expression of these proteins is useful for correct hair regrowth, whether during the physiological cycle or after chemotherapy-induced alopecia. CONCLUSIONS: Expression of caveolin-1 within the multipotent cell compartment of the hair follicle can explain the resistance of bulge cells to many chemotherapeutics, suggested by the reversibility of chemotherapy-induced alopecia.     

谷氨酸受体拮抗剂对恶性黑素瘤WM451LU细胞增殖、迁移的调控作用及相关机制研究

目的 探讨谷氨酸受体拮抗剂对恶性黑素瘤WM451LU细胞增殖、迁移的调控作用及相关机制。方法 取对数生长期人侵袭性恶性黑素瘤WM451LU细胞,分为3组,分别接受100 μmol/L谷氨酸受体拮抗剂MK?801（MK?801组）、10 μmol/L谷氨酸受体拮抗剂CPCCOEt（CPCCOEt组）或单纯培养基（对照组）处理。24 h后,噻唑蓝（MTT）法检测细胞增殖率,划痕实验检测细胞迁移能力,免疫印迹法检测增殖细胞核抗原（PCNA）、细胞膜及胞质中蛋白激酶Cα（PKCα）以及磷酸化MAPK（p?MAPK）表达水平。结果 处理24 h后,对照组、MK?801组以及CPCCOEt组细胞增殖率分别为100% ± 1.1%、63% ± 3.1%、60% ± 2.4%,后两组与对照组比较,差异均有统计学意义（P < 0.05）。划痕实验结果显示,对照组无细胞带随着时间的推移而逐渐变窄,划痕趋于愈合状态,而经MK?801及CPCCOEt作用后,无细胞带的变窄速度要明显缓慢,培养24 h后无细胞带仍然较宽,缩窄程度不明显。MK?801及CPCCOEt组细胞PCNA蛋白表达水平分别为77.0% ± 5.4%和72.0% ± 4.2%,显著低于对照组（100.0% ± 1.3%）,差异均有统计学意义（P < 0.05）。对照组、MK?801组以及CPCCOEt组细胞膜上PKCα表达水平分别为0.38 ± 0.01、0.12 ± 0.02、0.14 ± 0.02,后两组与对照组比较,差异均有统计学意义（P < 0.05）。MK?801组及CPCCOEt组p?MAPK表达水平分别为0.48 ± 0.03、0.36 ± 0.04,显著低于对照组（1.00 ± 0.02）,差异均有统计学意义（P < 0.05）。结论 体外阻滞谷氨酸受体能够抑制WM451LU细胞增殖、迁移,该作用可能部分由PKCα?MAPK信号通路介导。     

重组Ad-SOCS1介导的树突状细胞源外泌体对银屑病样小鼠模型的影响

目的:明确重组腺病毒(Ad-SOCS1)介导的树突状细胞(DCs)分泌的外泌体对银屑病样小鼠模型的影响。方法:Ad-SOCS1腺病毒感染小鼠骨髓来源的DCs,分离纯化培养物中的外泌体,Western blot分析鉴定外泌体中的CD63、SOCS1和ICAM-1蛋白。咪喹莫特(IMQ)诱导10只银屑病样小鼠模型,其中5只给予外分泌体治疗(外分泌体组)组,5只作为对照(IMQ组)。RT-PCR检测小鼠外周血IL-17A、IL-22和IL-23 mRNA的表达水平。结果:外泌体中能够鉴定到SOCS1、CD63和ICAM-1蛋白。外分泌体组小鼠的银屑病样表现较IMQ组轻。外分泌体组小鼠外周血IL-17A和IL-23 mRNA的表达低于IMQ组(P0.01),IL-22水平两组间无显著差异(P0.05)。结论:Ad-SOCS1感染DC后培养物分离的外泌体可改善银屑病的症状,其机制可能与外泌体SOCS1抑制IL-17A有关。     

Thy-1+ dendritic epidermal cells in mice: precursor frequency analysis and cloning of concanavalin A-reactive cells

Bulk cultures of mouse Thy-1+ dendritic epidermal cells (Thy-1+ DEC) have been shown to proliferate in response to concanavalin A (Con A) and IL-2, to secrete IL-2-like growth factors, and to lyse target cells such as YAC-1. Limiting dilution microculture was utilized in order to determine the precursor frequency of Con A-responsive Thy-1+ DEC in suspensions of AKR/J epidermal cells as well as whether these several functional activities all reside within a single Thy-1+ DEC precursor. Precursor frequency analysis of cultures established with limiting numbers of FACS-purified Thy-1+ DEC, irradiated syngeneic splenic filler cells and exogenous IL-2 indicated that approximately 20% of Thy-1+ DEC proliferated in response to Con A. Parallel microcultures in which purified Thy-1+ DEC were plated at a density of 0.5 cells/well were used to establish clones. Twenty clones were characterized phenotypically, and ten of these were also tested for their capacities to proliferate in response to Con A or IL-2, to secrete IL-2-like growth factors, and to exhibit cytotoxicity. All clones were Thy-1+ and L3T4-, but while most were also Lyt-2-, several contained 3%-18% dull Lyt-2+ cells. Functional studies revealed that each clone displayed all of the above functional activities, albeit with substantial quantitative variation. Clones with the highest cytotoxic activity had relatively low responsiveness to Con A or IL-2 and included all clones containing dull Lyt-2+ cells; conversely, clones with the highest proliferative responses had relatively low cytotoxic activity and were all Lyt-2-. This degree of functional and phenotypic heterogeneity among cloned Thy-1+ DEC may reflect their particular states of activation or differentiation; whether it reflects the biologically relevant in vivo activities of these cells must still be determined.