bluuebunny/crossref_metadata_2025 huggingface dataset:
The central rôle of T‐cells in allergic sensitization and IgE regulation
Authors: Renz Harald
Published: April 2006

Abstract The atopic phenotype develops on the basis of a genetic predisposition. Several candidate genes and chromosomal regions have been recently identified that may play a role in the development of allergic sensilization and total IgE production, including genes encoding MHC and T‐cell receptor (TCR) molecules, cytokines and others. Genetic predisposition triggers and immunological dysregulation which is controlled by CD4+ T‐cells. (Specialized) antigen presenting cells process and present allergenic peptides (T‐cell epitopes) on MHC class II molecules to T‐cells that recognize MHC plus peptide using the TCR. Cognate and non‐cognate interaction results in T‐cell activation. Selective stimulation of the allergen specific T‐cells is the result of allergen‐specific sensitization. These T‐cells are characterized by (simultaneous) production of IL‐3, IL‐4, IL‐5 (and may be IL‐13). These cytokines control the production of IgE by B cells and play a critical role in the activation and differentiation of effector cells of the allergic response (such as eosinophils and mast cells). In additon to MHC‐TCR interaction and cytokine production, ligation of CD40 and CD40L represents an additional requirement for the production of functional IgE molecules. Immediate hypersensitivity responses are characterized by an early phase response (triggered by many mediators released from effector cells following allergen exposure. IgE cross‐linking and activation of signal transduction pathways) and a late phase response that is mediated to a large extend by the influx of T‐cells and effector cells into the site of allergic inflammation. Deliniation of the immunological mechanisms that result in allergic sensitization will contribute to the development of specific immunomodulatory strategies aimed to prevent the development of allergies.
Calcium: a crucial consideration in serum‐free keratinocyte culture
Authors: Daniels J. T. , Harris I. R. , Kearney J. N. , Ingham E.
Published: April 2006

Abstract This investigation was conducted when previously rcpealable experimental data became impossible to reproduce when using keratino‐cytes cultured in serum‐free medium. Differences in calcium molarity between batches of medium were identified as a source of variation in cultured keratinocyte populations. The susceptibility of cultured keralinocytes to even small alterations in calcium molarily has been demonstrated. 2 regular medium batches were compared with a special preparation of medium, devoid of calcium chloride then supplemented with a known concentration of calcium ions. Culture progress in each medium was assessed by: morphological observation, % cells expressing involucrin and proliferating cell nuclear antigen, cell attachment, growth rate and colony forming efficiency. In order to control the phenotype of cultured kera‐tinocytes, in a rcpoducible system, it is recommended that serum‐free keratinocyte medium is purchased with the omission of calcium chloride. Supplementation of this medium may then be made by the investigator to suit individual culture requirements.
Interaction of palladium ions with the skin
Authors: Santucci B. , Cristaudo A. , Cannistraci C. , Picardo M.
Published: April 2006

Abstract 87 subjects sensitive to both nickel sulfate and palladium‐chloride pet., were contemporaneously patch retested to nickel sulfate 5% pet., metallic palladium chloride 1% pet. and to palladium chloride 1% aq. Whilst all subjects reacted to nickel sulfate and palladium chloride pel., only 3 reacted to palladium chloride aq. No positive reactions were found to metallic palladium. The negative results to palladium chloride aq. are probably due to the formation of a new palladium ion (PdC4)2−, achieved on adding an amount of hydrocloric acid to the aqueous solution of PdCl2. The findings seem to demonstrate that the allergic reaction to palladium depends on the arrangement of the metal electrons. The sensit‐ization to palladium does not seem to be dependent on the element itself but on the complexes formed by the different compounds. The concomitant reactions to nickel and palladium ions could be dependent on the generation of similar complexes between the ions and the skin proteins.
Mast cell ontogeny and apoptosis
Authors: Metcalfe Dean D. , Mekori Joseph A. , Rottem Menachem
Published: April 2006

Abstract The regulation of tissue mast cell number depends both on the rate of production of mast cell precursors from bone marrow and the length of survival of mature mast cells within tissues. Mast cells develop from bone marrow under the influence of both interleukin‐3 (IL‐3) and the c‐kit ligand, also known as stem cell factor (SCF). In humans, the mast cell precursor is CD34+, FcERI‐. Mast cell precursors with time become less responsive to IL‐3 and more responsive to SCF. Mast cell proliferation directed by SCF is enhanced by other cytokines including both IL‐4 and IL‐10. Once mast cell precursors target to tissues, their survival may largely be dependent upon the local production of SCF. Withdrawal of IL‐3 or SCF results in mast cell apoptosis; SCF rescues mast cells following IL‐3 withdrawal. TGF‐beta prevents this SCF rescue. Engagement of extracellular matrix by integrin receptors may also effect mast cell numbers. Thus, in the final analysis, mast cell numbers, while relatively constant in the normal state, may be up‐regulated by altering the rate of their production centrally or length of survival in the periphery.
Cytokines involved in growth and differentiation of human basophils and mast cells
Authors: Valent Peter
Published: April 2006

Abstract Mast cells and basophils are multifunctional effector cells of the immune system. Both are myeloid cells and originate from multipotent hemopoietic progenitor cells. Usually, human basophils complete their differentiation in the bone marrow. In contrast, mast cells usually undergo differentiation in extramedullary organs. During the past few years, growth factors for human basophils and a growth factor for human mast cells have been identified. Interleukin‐3 is the most potent differentiation factor for human basophils and activates mature basophils via high affinity binding sites. Other basophil agonists are GM‐CSF. IL‐5. NGF and certain chemokines (IL‐8, MCP‐1). Mast cells apparently loose cytokine binding sites during mastopoiesis and as mature cells, do not express detectable amounts of IL‐3R, GM‐CSFR or 1L‐8R. However, in contrast to other myeloid cells, mast cells express SCF receptor/c‐kit during mastopoiesis and on mature cells. Furthermore, the ligand of c‐kit, SCF, induces differentiation of human mast cells from their progenitor cells and upreglates effector functions in mature mast cells.
Mast cells as modulators of hair follicle cycling
Authors: Maurer Marcus , Paus Ralf , Czarnetzki Beate M.
Published: April 2006

AbstractWhile the central rôle of mast cells (MC) in allergy and inflammation is well‐appreciated, much less is known about their physiological functions. The impressive battery of potent growth modulatory MC products, and increasing evidence of MC involvement in hyperproliferalive and librotic disorders suggest that tissue remodelling may be one of those, namely in the skin. Here, we delineate why this may best be studied by analysing the potential role of MC in hair growth regulation. On the background of numerous, yet widely under‐appreciated hints from the older literature, we summarize and discuss our recent observations from the C57BL/6 mouse model for hair research which support the concept that MC are functionally important modulators of hair follicle cycling, specifically during anagen development. This invites to exploit the murinc hair cycle as a model for dissecting the physiological growth modulatory functions of MC and encourages the exploration of MC‐targeting pharmaceutical strategies for the treatment of hair growth disorders.
The induction of the α‐1‐adrenoceptor signal transduction system on human melanocytes
Authors: Schallreuter Karin U. , Körner Christa , Pittelkow Mark R. , Swanson Norma N. , Gardner Michael L. G.
Published: April 2006

Abstract Human melanocytes established in MCDB‐153 culture medium do not express α1‐, β1‐, β‐2 adrenoceptors without extracellular stimulation. The addition of 50×10−9 M norepinephrine to the medium causes a time‐dependent induction of α‐1‐adrenoceptors with 4.278 receptors/melanocyte after 24 h. Under the same experimental conditions, the dendricity of melanocytes as well as melanogenesis was unaffected over 60 h. Since keralinocytes hold the full capacity for catecholamine biosynthesis but melanocytes lack this system, the secretion of catecholamines from keratinocytes appears to be of critical importance to the α‐1‐adrenoceptor in melanocytes, underlining the symbiosis of both cells in the epidermal unit.
Modulation of Ia+ Langerhans cell numbers in vivo by cultured epidermis derived supernatants and by GM‐CSF
Authors: O'Sullivan Gabrielle M. , Sluyter Ronald , Boswell Christopher M. , Barnetson R. St. C. , Halliday Gary M.
Published: April 2006

Abstract This paper demonstrates that epidermal cells in culture produce an activity which can increase the frequency of Ia+ epidermal Langerhans cells (LC). This was achieved by treating mice topically with a mixture containing supernatant derived from primary culture of murine epidermis (ES) and a synthetic corticosteroid, triamcinolone acetonide (TAG). The presence of the supernatant in the mixture partially protected the Ia+ LC from depletion by the steroid. The Ia+ LC frequency increasing activity was measured as the difference between the Ia+ LC frequency due to treatment with steroid mixed with supernatant and the Ia+ LC frequency due to treatment with steroid mixed with negative control medium. The mean frequency of Ia+ LC in epidermis treated with TAC mixed with ES was 606(SD 43) cells/mm2, as compared with 486 (SD 68) cells/mm2 in the epidermis treated with TAC mixed with control medium. The activity appeared to be caused by (a) proteinaceous factor(s). A fraction of ES which was retained above a ≥10 KDa molecular weight cut‐off membrane was capable of partially protecting Ia+ LC frequency from TAC depletion. Supernatants from cultured lymph nodes, dermis as well as the squamous cell carcinoma lines T7 and T79, but not the human osteosarcoma cell‐line 143B, also contained similar activities. We demonstrate that GM‐CSF also increased the number of Ia+ epidermal LC when applied topically to mouse skin in this system. Therefore, using this Ia+ LC frequency modulation system, we propose that GM‐CSF is one example of a cytokine which may be involved in the regulation of Ia+ LC numbers in epidermis and that epidermal cells produce factors which can increase the number of Ia+ LC.
Neuropeptides accentuate interleukin‐4 induced human immunoglobuline E synthesis in vitro
Authors: Aebischer Iwan , Stämpfli Martin R. , Miescher Sylvia , Horn Michael , Zürcher Adrian W , Stadler Beda M.
Published: April 2006

Abstract Corticotropin releasing factor, adrenocorticotropic hormone (ACTH) and alpha‐melanocyte stimulating hormone either inhibit or enhance in a dose‐dependent fashion an interleukin‐4 (IL‐4) driven human IgE synthesis in vitro. Here, we show that culture conditions strongly influence the earlier observed dose‐ and donor‐dependent effects of adrenocorticotropic hormone. The effect of ACTH on IgE synthesis became only apparent late during culture periods, suggesting an indirect effect via the cellular microenvironment rather than by acting directly at the level of B‐cell isotype switching. Thus, we studied other proopiomelanocortin (POMC) derived peptides and neuropeptides known to influence the cellular microenvironment. Indeed, similar modulatory effects on IgE synthesis were also observed by the addition of other proopiomelanocortin‐derived peptides such as α‐, β‐, and γ‐endorphins as well as by the opioid binding pentapeptide Leu‐enkephalin. Furthermore the neuropeptide substance P accentuated an IL‐4 or an IL‐4 and anti‐CD40 antibody driven class switch to IgE. In contrast to ACTH, substance P interfered not only with IgE synthesis but also with the synthesis of the other immunoglobulin isotypes. Thus, systemically acting neuroendocrine peptides such as ACTH and locally acting neuropeptides such as the enkephalins and substance P can modulate the magnitude of an IL‐4 induced IgE response.
Decreased expression of α2β1 integrin in scleroderma fibroblasts
Authors: Kozlowska Ewa , Sollberg Stephan , Mauch Cornelia , Eckes Beate , Klein C. Eberhard , Krieg Thomas
Published: April 2006

Abstract Systemic scleroderma (SSc) is a complex connective tissue disorder of unknown etiology. In early stages of the disease, libroblasts are activated to produce large amounts of collagen with subsequent fibrosis. Collagen metabolism of fibroblasts is modulated by their contact with the extracellular matrix (ECM), which involves distinct receptors on the cell surface, mainly belonging to the integrins. We investigated the expression of collagen receptor α2β1, in SSc and normal fibroblasts, since this receptor has been shown to be utilized by fibroblasts for adhesion to and reorganization of collagen I. 9 strains of scleroderma fibroblasts grown as monolayer cultures were first analyzed with respect to their collagen I expression. 6 of these strains were similar to controls (“low” producers) and 3 strains showed up to 2–3 × higher levels of collagen I mRNA expression (“high” producers). Northern hybridization using a cDNA probe specific for the α2 integrin subunit revealed a decrease of the corresponding mRNA in SSc fibroblasts as compared to controls (75% versus 100%). “High” collagen producing cell strains displayed the lowest values for α2 integrin mRNA. The decrease of α2 integrin subunit expression at the mRNA level in selected fibroblasts was further substantiated by radioimmunoprecipitation using specific mAbs directed against α2 integrin subunit. No significant changes in β1 integrin expression could be observed‐neither at mRNA nor at the protein level. Our data indicate a correlation between excessive synthesis of collagen and low levels of α2 integrin subunit expression in SSc fibroblasts. Further experiments should clarify whether this observation is a phenomenon specific for scleroderma or whether it reflects an “activated” state of fibroblasts.
Interactions of sulfates of divalent metals in nickel‐sulfate‐sensitive patients
Authors: Santucci B. , Cannistraci C. , Cristaudo A. , Picardo M.
Published: April 2006

Abstract 70 nickel‐sensitive subjects who previously gave positive patch test response lto 10 μl of nickel sulfate 0.1 M, were patch tested to 10 μl of mixed aqueous solutions containing nickel sulfate 0.1 M +magnesium sulfate 0.3 M, nickel sulfale 0.1 M+zinc sulfate, 0.3 and 0.5 M, respectively, nickel sulfate 0.1 M+ manganese sulphate 0.3 and 0.5 M, respectively nickel sulphate 0.1 M+ cadmium sulfate 0.1 and 0.3 M, respectively, nickel sulfate 0.1 M + iron sulfate (III) 0.1 and 0.3 M, respectively, and to 10 μl of aq. cadmium sulfate 0.1 M, aq. cadmium sulfate 0.3 M, aq. iron sulfate 0.1 M, aq. iron sulfate 0.3 M. The results showed that, whilst sulfates of divalent metals with similar size and redox properties (Mg, Zn and Mn) were able to reduce or to suppress, in a dose‐dependent way, the majority (75%) of nickel reactions, those with large radius and different oxidation state(Fe III), generally gave an increase in the reactions. In about 15% of the tested subjects, an increase in all the positive reactions to the mixed solutions was found. The findings seem to demonstrate that in only a majority but not all of nickel sulfate allergic reactions, is Ni(II) able to substitute for divalent ions with similar properties at the ion sites of some proteins. This tendency reproduces the results of experimental systems, in which nickel toxicity and cancerogenity are considered responsible. In contrast, in about 15% of the tested subjects, there was a general enhancement of the reactions. In these cases, either the occurrence of a “hyper‐irritable” skin caused by the adopted test system or, more likely, the formation of Ni complexes with different geometries, is hypothesized.
Merkel cells and Merkel cell carcinoma express the BCL‐2 proto‐oncogene
Authors: Plettenberg Andreas , Pammer Johannes , Tschachler Erwin
Published: April 2006

Abstract The bcl‐2 proto‐oncogene, which is involved in the regulation of apoptosis, is expressed in a wide varity of fetal and adult tissues. We and others have demonstrated recently that in the human skin melanocytes, nevus cells and melanoma cells express bcl‐2 constitutively. In the present study, we have analysed the expression of bcl‐2 in Merkel cells and in Merkel cell carcinomas. In 2 colour immunofluorescencc staining, normal human Merkel cells as identified by the expression of cytokeratins 8, 18 and 20, were also anti‐bcl‐2 positive. Staining of paraffin sections of Merkel cell carcinomas with an anti‐bcl‐2 monoclonal antibody revealed strong bcl‐2 protein immunoreactivtiy in all 5 tumors tested. Serial sections of Merkel cell carcinomas stained with the monoclonal antibodies CK 20, CAM 5.2, anti‐neuron‐specific enolase and anti‐bcl‐2 showed that the anti‐bcl‐2 reactive cells were indeed tumor cells. Our data demonstrate for the first time, that normal human Merkel cells and Merkel cell carcinomas express bcl‐2 constitutively. Considering the biological function of the bcl‐2 proto‐oncogene, i.e., its anti‐apoptotic effect, it is conceivable that in the near future, modulations of the expression of this protein may offer a new strategy in the therapy of bcl‐2 expressing tumors such as Merkel cell carcinoma.
Granulocyte/macrophage‐colony‐stimulating factor induces the migration of human epidermal Langerhans cells in vitro
Authors: Rupec R. , Magerstaedt R. , Schirren C. G. , Sander E. , Bieber T.
Published: April 2006

Abstract In the present study, we investigated the in vitro migratory activity of human epidermal Langerhans cells (LC). Freshly isolated LC exhibit very low spontaneous migration. In contrast, a strong migration is recorded 6 h after the isolation. This migration is due to the presence of GM‐CSF released by surrounding keratinocytes in vitro. Picomolar concentrations of GM‐CSF promote the migration of LC, but nanomolar concentrations are inhibitory. Checker‐board experiments indicate that GM‐CSF acts as a chemokinetic mediator for LC. Bulk cultured LC exhibit a significant decrease of their spontaneous migration but retain the capacity to respond to GM‐CSF only at nanomolar concentrations. In contrast, LC cultured in the presence of picomolar concentrations of exogenous GM‐CSF exhibit a spontaneous migratory activity comparable to that of 6 h rested LC but do not respond to GM‐CSF. These results suggest that GM‐CSF represents an essential factor triggering the egress of LC from their epidermal environment.
Absence of MHC class II antigen on mast cells at sites of inflammation in human skin
Authors: Lipski S. , Grabbe J. , Henz B. M.
Published: April 2006

Abstract Since the presence of major histocompatibility complex (MHC) antigens has recently been reported on murine and human mast cells under various conditions, we have investigated their expression on mast cells in different types of cutaneous inflammation. Cryostat sections from lesional biopsies of patients with psoriasis, atopic eczema, chronic urticaria, lichen planus, bullous pemphigoid and urticaria pigmentosa were immunohistochemically stained with monoclonal antibodies against MHC class I and class II antigens using a double staining APAAP/toluidine blue methodology. While strongly positive staining with the antibody directed against MHC class I antigens was found on nearly all mast cells in normal skin and in inflammatory dermatoses, reactivity for HLA‐DR and HLA‐DQ antigens on mast cells could not be detected, except for less than 2% of cells with doubtful staining. Human mast cells therefore probably play no significant rôle as antigen‐presenting cells in the conditions studied.
Effects of UVB irradiation on keratinocyte growth factor (KGF) and receptor (KGFR) expression in cultured human keratinocytes
Authors: Zhou Youwen , Lee Hyung‐Suk T. , Kooshesh Fatemeh , Fujisawa Hiroshi , Sauder Daniel N. , Kondo Seiji
Published: April 2006

Abstract Keratinocyte growth factor (KGF) and its receptor (KGFR) are thought to play important roles in normal keratinocyte growth and differentiation. Since UVB radiation is known to influence keratinocyte growth, we sought to determine whether UVB would alter the expression of KGF and KGFR. Using a reverse‐transcription coupled polymerase chain reaction (RT‐PCR). the present study examined the expression of KGF and KGFR mRNA in cultured normal human keratinocytes exposed to UVB irradiation. Total cellular RNA was extracted from cultured keratinocytes at various time points after irradiation, reverse transcribed and used for PCR amplification using primers specific for KGF and KGFR. Constitutive expression of KGFR mRNA, but not KGF mRNA, was detected in normal cultured human keratinocytes. After UVB irradiation at 300 J/m2, the KGF mRNA remained undelectable while the KGFR mRNA level was significantly decreased. The downregulation of KGFR mRNA expression was also confirmed by Northern blot analysis. Immunohistochemical studies demonstrated a decreased positive signal of KGFR in human keratinocytes after UVB irradiation. Our results suggest a possible role for the KGF‐KGFR signalling pathway in the skin after exposure to UVB, and that UVB‐induced growth inhibition of keratinocytes in hyperproliferative skin disorders may be related to downregulation of KGFR.
Unusual wrinkle formation after temporary skin fixation followed by UVB irradiation in hairless mouse skin
Authors: Takema Yoshinori , Fujimura Tsutomu , Ohsu Hiroyuki , Imokawa Genji
Published: April 2006

Abstract Generally, many wrinkles form on the human face, and temporary wrinkles eventually become permanent. We evaluated the effects of temporary skin fixation on wrinkle formation after UVB irradiation using the back skin of hairless mice. In the group treated with UVB irradiation immediately after production using cyanoacrylate resin of an artificial groove parallel to the midline, wrinkles formed parallel to the midline, an uncommon direction for wrinkle formation in this mouse model. These wrinkles did not disappear even when the skin was stretched. No such changes were observed in the group in which only the temporary groove alone was produced without UVB irradiation. In 3‐D surface parameter analysis, all roughness parameters in the group treated with UVB irradiation immediately after production of an artificial groove were significantly increased relative to the age‐matched control group. In contrast, no differences were observed between the group in which only the temporary groove alone was produced without UVB irradiation and age‐matched controls. The results of this study suggest that both a temporary groove in the skin and UVB irradiation are necessary for wrinkle formation in the back skin of hairless mice.
Plectin and human genetic disorders of the skin and muscle
Authors: Uitto Jouni , Pulkkinen Leena , Smith Frances J. D. , McLean W H Irwin
Published: April 2006

Abstract Recent progress in understanding the molecular organization of the cutaneous basement membrane zone (BMZ) has revealed an intricate network of structural proteins necessary for stable association of the epidermis to the underlying dermis. Molecular genetics of the cutaneous BMZ has also revealed that defects in as many as nine distinct genes within the dermal‐epidermal junction which result in different forms of epidermolysis bullosa (EB). a group of heritable mechano‐bullous disorders. We have recently demonstrated that a variant of EB associated with late‐onset development of muscular dystrophy (EB‐MD. MIM no. 226670) results from mutations in the gene encoding plectin (PLEC1). a cytoskeleton associated attachment protein present in the hemidesmosomal inner plaque and the sarcolemma of the muscle. Consequently, mutations in this multi‐functional gene/protein system can result in phenotypic manifestations of EB‐MD both in the skin and the muscle. In this overview, we will summarize the domain organization of plectin and the structure of the corresponding gene (PLEC1). as well as the genetic basis of EB‐MD in families studied thus far. Elucidation of the molecular basis of this subtype of EB adds to our understanding of the structural and functional complexity of the cutaneous BMZ.
A screening of skin changes, with special emphasis on neurochemical marker antibody evaluation, in patients claiming to suffer from “screen dermatitis” as compared to normal healthy controls
Authors: Johansson O. , Hilliges M. , Han S.‐W.
Published: April 2006

Abstract In the present study, facial skin from so‐called “screen dermatitis” patients were compared with corresponding material from normal healthy volunteers. The aim of the study was to evaluate possible markers to be used for future double blind or blind provocation investigations. Differences were found for the biological markers calcitonin generelated peptide (CGRP), somatostatin (SOM), vasoactive intestinal polypeptide (VIP), peptide histidine isoleucine amide (PHI), neuropeptide tyrosine (NPY). protein S‐100 (S‐100). neuron‐specific enolase (NSR), protein gene product (PGP) 9.5 and phenyl‐ethanolamine N‐methyltransferase (PNMT). The overall impression in the blind‐coded material was such that it turned out easy to blindly separate the two groups from each other. However, no single marker was 100% able to pin‐point the difference, although some were quite powerful in doing so (CGRP, SOM. S‐100). However, it has to be pointed out that we cannot, based upon the present results, draw any definitive conclusions about the cause of the changes observed. Whether this is due to electric or magnetic fields, a surrounding airborne chemical, humidity, healing, stress factors, or something else, still remains an open question. Blind or double‐blind provocations in a controlled environment are necessary to elucidate possible underlying causes for the changes reported in this investigation.
Exposure of UVB‐sensitive mice to immunosuppressive doses of UVB in vivo fails to affect the accessory function or the phenotype of draining lymph node dendritic cells
Authors: Lappin M. B. , Kimber I. , Dearman R. J. , Norval M.
Published: April 2006

Abstract Following the application of sensitizing chemicals to the skin, hapten‐bearing Langerhans cells (LC) and possibly other cutaneous dendritie‐cells (DC) migrate to the draining lymph nodes (DLN) of mice and induce the proliferation of antigen specific effector T cells. This migration of DC to the DLN is required for the induction of primary immune responses. In certain strains of mice, irradiation with ultraviolet‐B light (UVB) before sensitization results in the suppression of contact hypersensitivity responses. in vitro investigations have suggested that one influence of UVB is to modify the ability of Langerhans cells (LC) to present antigen. In the present investigation, putative UVB‐induced alterations in lymph node DC in vivo were examined. Lymph node DC were analysed following exposure of C3H/HeN mice to an immunosuppressive dose of UVB (1440 J/m2) 48 and 24 h prior to skin painting with the sensitizers fluorescein isothiocyanate or oxazolone. In functional studies. DC prepared from the DLN of contact sensitized mice were examined for their ability to induce hapten‐specific secondary T‐lymphocyte proliferative responses or mixed lymphocyte reactions in vitro. It neither case was the activity of DC influenced by local exposure to an immunosuppressive dose of UVB. The migration of LC from the epidermis to the draining lymph node in response to contact sensitization is associated with increased expression of several membrane determinants necessary for effective antigen presentation, including intercellular adhesion molecule‐1 (ICAM‐I: CD54), B7‐2 (CD86) and la antigen. The expression of these molecules was identical on DC isolated from the DLN of UVB‐irradiated and from control, unirradiated mice. Thus, the immunosuppressive effect of UVB on Ihe cutaneous immune system may not necessarily reflect changes in the antigen‐presenting DC that accumulate in the DLN following skin sensitization.
Human keratinocytes constitutively express IL‐4 receptor molecules and respond to IL‐4 with an increase in B7/BB1 expression
Authors: Junghans V. , Jung T. , Neumann C.
Published: April 2006

Abstract In certain pathological conditions, such as atopic dermatitis, interleukin‐4 (IL‐4) can be detected in the skin. As the rôle of this cytokine in inflammatory skin lesions is not completely clear, we investigated its biological effects on skin keratinocytes. It was found that freshly isolated as well as cultured keratinocytes obtained from normal individuals express mRNA for the IL‐4 receptor (IL‐4R) and produce IL‐4R protein, as determined by How cytometry. Moreover, IL‐4 induced a proliferative response in keratinocyles after 1 day of culture and enhanced B7/BB1 expression in these cells. B7‐2 (CD86) mRNA and protein were neither detected on untreated nor IL‐4 treated keratinocytes. In contrast to interferon‐γ (IFN‐γ), IL‐4 did not induce ICAM‐1 (CD54) or HLA‐DR‐expression. Keratinocytes which had been treated with IL‐4 showed an enhanced ability to stimulate allogeneic T‐cell proliferation in the presence of staphylococcus enterotoxin B (SEB),(p<0.01). Neutralizing anti‐ B7/BBI monoclonal antibodies did not block this effect. These results indicate that other molecules than B7/BB‐I, HLA‐DR or ICAM‐1 on IL‐4‐activated keratinocytes may be involved in T‐cell stimulation. In conclusion our results suggest, that locally produced IL‐4, besides modulating keratinocyte membrane molecules, may enable keratinoeytes to interact with skin infiltrating lymphocytes.
Melanotropic peptide receptors: membrane markers of human melanoma cells
Authors: Jiang Jinwen , Sharma Shubh D. , Fink Jody L. , Hadley Mac E. , Hruby Victor J.
Published: April 2006

Abstract The objectives of this research were to determine whether melanotropin receptors are characteristic (constant) membrane markers of human melanoma cells. Methodologies were developed to visualize these receptors by fluorescence microscopy. Multiple copies (10–20) of both [Nle4.D‐Phe7]α‐MSH, a superpotent analog of α‐melanocyte stimulating hormone (α‐MSH). and a fluorophore, were conjugated to polyvinyl alcohol (PVA). Incubation in the presence of the multivalent macromolecular conjugate (FITC‐PVA‐MSH) resulted in binding of human epidermal melanocytes and keratinocytes and human melanoma cells (both melanotic and amelanotic) to the fluorescent conjugate. Binding of the conjugate to the cells exhibited a unique cluster pattern (capping) suggesting a receptor internalization related phenomenon. Most importantly, every cell of every melanoma cell line, melanotic or amelanotic. possessed receptors as visualized by fluorescence microscopy. Since the cells were not synchronized, some binding apparently took place during all phases of the cell cycle. Therefore, receptor expression appears not to be cell‐cycle dependent. Specificity of binding of FITC‐PVA‐MSH was demonstrated by several studies, (i) Binding of the conjugate to melanoma cells could be blocked by prior incubation of the cells in the presence of the unconjugated hormone analog: [Nle4,D‐Phe7]α‐MSH. (ii) The macromolecular conjugate lacking bound ligand (FITC‐PVA) did not bind to the melanoma cells, (iii) Another peptide, a substance‐P analog, attached to the substrate (FITC‐PVA‐SP) failed to bind to the cells, (iv) With the exception of keratinocytes, other cells of nonmelanocyte origin (e.g., fibroblasts, spleen, liver, kidney cells, and mammary cancer cells, lung cancer cells) did not bind to the conjugate. Thus, cell‐specific melanotropin receptors appear to be characteristic cell surface markers of epidermal melanocytes, keratinocytes, and melanoma cells. In several human melanoma cell lines these receptors appeared to be functional since [Nle4,α‐Phe7]α‐MSH stimulated tyrosinase activity. Fluorescent melanotropin conjugates might prove useful in determining whether all human melanoma (primary and metastatic) tumors possess such receptors. These receptors might then provide targets for melanotropic peptides for the identification, localization, and chemotherapy of melanoma.
Plectin abnormality in epidermolysis bullosa simplex Ogna: non‐responsiveness of basal keratinocytes to some anti‐rat plectin antibodies
Authors: Koss‐Harnes D. , Jahnsen F. L. , Wiche G. , Soyland E. , Brandtzaeg P. , Gedde‐Dahl T.
Published: April 2006

Abstract Epidermolysis bullosa (EB) is a heterogeneous group of genetic bullous skin diseases. The EB simplex group (EBS) is characterized by intraepidermal blistering. EBS‐Ogna was first described as a separate entity based on clinical studies. Later genetic linkage of EBS‐Ogna to the GPT locus for glutamate pyruvate transaminase (alanine transaminase) was delected and GPT was assigned to chromosome 8. then to the terminal long arm band 8q24. Plectin is an abundant and widespread cytoskeletal protein which has been proposed as a general crosslinking element of intermediate filaments. Human plectin has recently been cloned and in situ hybridized to chromosome 8q24. To examine whether plectin could be associated with EBS‐Ogna we performed an immunohistochemical study with a panel of mAbs to rat plectin. Interestingly, 2 of these mAbs showed strong intracellular staining of the suprabasal and basal layer of the epidermis in all control samples, whereas no reactivity of the basal layer was found in the Ogna group. These results strongly suggest that plectin is involved in the pathogenesis of EBS‐Ogna.
Establishment and characterization of a novel human cell line exhibiting both immunophenotypic markers of monocyte/macrophage and natural killer cell lineages from peripheral blood of a patient with atopic dermatitis
Authors: Hamamoto Y. , Nagai K. , Muto M. , Nakamura K. , Yasui H. , Asagami C.
Published: April 2006

Abstract Large amounts of homogeneous cells are not always available for in vitro studies of inflammatory skin disorders. Here we demonstrate that a novel cell line, termed YAA, has been established from peripheral blood mononuclear cells, which were separated by the Ficoll method, of a patient with atopic dermatitis. YAA cells were grown in suspension culture. The cytochemical staining showed a positive reaction for α‐naphthyl butyrate esterase, which was completely inhibited by sodium fluoride, but a negative result for periodic acid‐Schiff, peroxidase and alkaline phosphatase. A large population of YAA cells exhibited phenotype of CD33 and CD56 but neither of CD2 nor CD3. The phorbol ester‐stimulated YAA cells produced a considerable amount of tumor neerosis factor‐α. These findings suggest that YAA might be a monocytoid line with an additional phcnolype specific for natural killer cells.
Antinuclear antibodies in patients with lichen planus
Authors: Carrizosa Ana M. , Elorza Félix L. , Camacho Francisco M.
Published: April 2006

Abstract Lichen planus (LP) is a mucocutaneous syndrome of yet uncertain pathogenesis, and it has usually been considered to be a dermatosis without antinuclear antibodies (ANA) nor other specific auto‐antibodies. Over 10 years ago a series of indirect immunofluorescence researches with patients' lesional skin and serum disclosed the presence of lichen planus specific antigens (LPSA). After this, a number of substrates have been submitted for evaluation. In this study we have carried out indirect immunofluorescent test in relation with different substrates, with the aim of verifying whether the negative results previously obtained were due to poor sensitivity of the substrates employed. Subsequently we have compared the results obtained in the erosive forms of LP with those obtained in the non‐erosive forms. We have concluded that rat oesophagus is a better substrate for the detection of ANA in patients with LP, as it has proved to have a positivity rate of 40.42%. Monkey oesophagus has provided a rate of 27.6%, and HEP‐2 cells and rat liver have proved to be unsuitable. In addition, we have observed that the frequency of ANA is higher in the erosive forms of LP (P= 0.0389). In this article we demonstrate that the presence of ANA in patients with LP depends on the substrate employed, the most suitable substrate being rat oesophagus. Also, we demonstrate that ANA is more frequently observed in patients with erosive LP.
Significant reduction of human monocyte chemotactic response to monocyte‐chemotactic protein 1 in patients with primary and metastatic malignant melanoma
Authors: Müller Rembert , Zheng Min , Mrowietz Ulrich
Published: April 2006

Abstract The recruitment of leukocytes from the peripheral blood is a key event for the development and composition of the inflammatory infiltrate in solid tumors and tumor metastases like malignant melanoma. Tumor‐infiltrating lymphocytes (TIL) and tumor‐associated macro‐phages (TAM) are thought to play a crucial rôle in tumor immunosurveillance. In malignant melanoma expression and secretion of monocyte‐chemotactic protein 1 (MCP‐1) have been demonstrated. MCP‐1 serves as an attractant for monocytes and activated T‐cells. In this study we addressed the question whether circulating monocytes show altered chemotaxis to MCP‐1. Therefore the chemotactic responsiveness of monocytes towards MCP‐1 was investigated in patients with primary and metastatic melanoma and compared to patients with basal cell carcinoma and healthy persons. The results show that monocytes from melanoma patients showed a significantly decreased chemotactic migration towards MCP‐1 while chemotaxis to the stimulus N‐formyl‐methionyl‐leucyl‐phenylalanine (FMLP) remained normal. Patients with basal cell carcinoma showed normal monocyte chemotaxis to all stimuli tested. In primary melanoma, there was no relation of the number of TAM or TIL to ihe decreased chemotaxis of circulating monocytes to MCP‐1. From these data it can be concluded that circulating monocytes from patients with primary and metastatic melanoma show a MCP‐1‐specific decrease in chemotactic migration. This may be due to deactivation or modulation of the MCP‐1‐receptor expression on these cells.
Expression pattern of human hair keratin basic 1 (hHbl) in hair follicle and pilomatricoma
Authors: Règnier Catherine H. , Asch Pierre‐Henri , Grosshans Edouard , Rio Marie‐Christine
Published: April 2006

Abstract Using in situ hybridization. human hair keratin basic I (hHbl) gene expression was investigated in human normal scalp. hHbl transcripts were specifically detected in the cortical cells of hair shaft but neither in the outer and inner root sheaths, nor in the hair cuticle or the medulla. hHbl expression was detected strongly in cortical cells located from the beginning of the keratogenous zone up to the isthmus. These data specify the localization of hHbl expression. Furthermore, neoplasms with follicular differentiation, including trichoblastoma. trichoepithelioma, pilomatricoma. pilar carcinoma and basal‐cell carcinoma, were analysed for hHbl gene expression. One of the 4 pilomatricoma specimens examined exhibited a very high level of hHbl transcripts. Interestingly, this labeling was specifically associated to a transitional cell layer en route to trichocytic differentiation, providing evidence that in pilomatricoma. epithelial germ cells can differentiate towards hair shaft keratinocytes before evolving in ghost cells.
Serum‐free conditions for the long term growth and differentiation of neoplastic canine keratinocytes*
Authors: Crameri F. M. , Varvayanis M. , Cromie B. R. , Rekers W. L. , Suter M. M.
Published: April 2006

Abstract Long term cultures of canine keratinocytes have been established but culture conditions currently used require supplementation with fetal bovine serum (FBS). Unfortunately. FBS contains many non‐defined components which may interfere with in vitro studies. This study describes the development of defined serum‐free culture conditions for neoplastic canine keratinocytes grown submerged and at the air‐liquid interface. Two commercially available serum‐free media established for human epidermal cells failed to support canine keratinocyte growth. In contrast, a defined serum‐free medium developed in our laboratory successfully supported proliferation of neoplastic canine keratinocytes for at least 40 passages. Cells showed a slower growth rate, but reached similar final densities and were morphologically identical to those cultured in FBS. Grown at the air‐liquid interface, the cells reached the same degree of differentiation as in vivo stratified squamous epithelium and cultures grown in FBS. These results demonstrate that canine keratinocytes require different serum‐free growth conditions than human cells. Neoplastic canine keratinocyte cultures, grown under serum‐free culture conditions, provide an ideal in vitro system for comparative studies of keratinocyte biology and pathogenesis of various dermatoses.
Different patterns of soluble adhesion molecules in systemic and cutaneous lupus erythematosus
Authors: Nyberg F. , Acevedo F. , Stephansson E.
Published: April 2006

Abstract Circulating isoforms of cellular adhesion molecules (CAMs) have been described recently, and elevated levels of certain sCAMs have been reported in various inflammatory diseases such as systemic lupus erythematosus (SLE). There are previously no reports on sCAMs in cutaneous LE. Sera from 61 patients with LE: systemic (SLE: n= 24), chronic cutaneous (discoid LE, DLE: n= 19) or subacute cutaneous (SCLE: n= 8), chronic biologically false positive (CBFP) reactors for syphilis (n= 10) and 32 controls were examined for sICAM‐1, sVCAM‐l and sE‐Se‐lectin with specific ELISA kits. Protocol forms were reviewed. We found significantly elevated levels of sE‐Selectin in patients with DLE and widespread cutaneous symptoms, and a correlation between active cutaneous disease as well as polymorphous light eruption (PLE) and elevated levels of sE‐Selectin. In contrast, patients with systemic LE did not have elevated levels of sE‐Selectin, but in concordance with earlier reports, sICAM‐1 and sVCAM‐l levels were elevated compared to controls in SLE. as well as in SCLE patients, which has not been reported previously. Since activated endothelial cells are the only source for E‐Selcetin, the elevated sE‐Selectin level in patients with widespread and active cutaneous disease suggests a more important role for endothelial cells in the pathogenesis of cutaneous LE than previously assumed.
Expression of c‐fos in cultured human nevus cells: an increase over melanocytes and melanoma cells
Authors: Rallis T. M. , Larkin M. T. , Schmidt L. A. , Meyer L. J.
Published: April 2006

Abstract Nevus cells exhibit growth characteristics in culture which differentiate them from melanocytes and melanoma cells. We examined the expression of c‐jun, c‐fos and jun‐B mRNA levels in cultures of different melanocytic cell types to determine if biologic differences among these cells was due to their level of proto‐oncogene expression. Because cell growth and differentiation are also known to be affected by serum conditions, the expression of c‐jun, c‐fos and jun‐B was examined under normal serum conditions and serum starved and repleted conditions which stimulates proto‐oncogene expression. Expression of c‐jun and jun‐B was not significantly different among the cell types studied under normal serum conditions, or serum starved and refed conditions and c‐fos was not detectable in any of the unstimulated cell types. In contrast, when the cells were serum starved and refed, the level of c‐fos expression was uniformly increased (2‐10 fold) in 3 different nevus ceil lines. This increase was not seen in normal melanocyte cultures or 2 melanoma cell lines. With serum deprivation and repletion, c‐fos was also elevated in 1 melanoma cell line. We conclude that the regulation of the proto‐oncogene c‐fos is different in nevus cells than in normal melanocytes, which may contribute to the different growth characteristics seen with nevus cells.
The mode of action of prostaglandin (PG) I1 analog, SM‐10906, on fibroblasts of hypertrophic scars is similar to PGE1 in its potential role of preventing scar formation
Authors: Zhou L.‐J. , Inone M. , Ono I. , Kaneko F.
Published: April 2006

Abstract The effects of prostaglandin (PG) I1, analog, SM‐10906 (SM‐6) and PGE1, on extracellular matrix formation and the release of cytokines by cultured normal human dermal fibroblasts (NDF) and hypertrophic scar fibroblasts (HSF) were compared in order to evaluate the clinical efficacy of PGs in preventing scar formation. In the present study, we measured type I collagen synthesis, collagenase activity, production of interleukin (IL)‐6, IL‐8, and transforming growth factor (TGF)‐β1, and levels of adenosine 3,5‐cyclic monophosphate (cAMP) in NDF and HSF cultured with or without PGs. The results demonstrated that HSF culture supernatants has a significantly higher level of type I collagen and TGF‐β1 than those of NDF. However, the levels of collagenase activity and IL‐8 in HSF were significantly lower in comparison to that of NDF. There was no substantial difference in IL‐6 production between two types of culture cells. On the other hand, PGE1 and SM‐6 significantly enhanced collagenase activity and raised the collagenase/type I collagen ratio in the HSF supernatants. In addition, both PGE1 and SM‐6 increased production of TGF‐β1, IL‐8 and IL‐6 and levels of cAMP in both cell types. However, they had no effect on the type I collagen synthesis of either types. These results suggest that, the stable PGI1 analog, SM‐6, similarly acts as PGE1 in HSF by increasing the activity of collagenase.
The 72‐kDa and the 92‐kDa gelatinases, but not their inhibitors TIMP‐1 and TIMP‐2, are expressed in early psoriatic lesions
Authors: Feliciani C. , Vitullo P. , D'orazi G. , Palmirotta R. , Amerio P. , Pour S. Mohammad , Coscione G. , Amerio P. L. , Modesti A.
Published: April 2006

Abstract Psoriasis is histologically characterized by hyperkeratosis and papillomatosis with elongated vessels in the upper dermis. In order to evaluate the role of gelatinases in remodelling psoriatic skin in this study we examined the production of the 72‐kDa (gelatinase A). 92‐kDa collagenase (gelatinase B) and their tissue inhibitors TIMP‐2 and TIMP‐1. A total of 19 patients affected by different types of psoriasis were included in this study. An immunohistochemical study on cryosections was performed using antibodies to 72‐kDa gelatinase, 92‐kDa gelatinase. TIMP‐1. TIMP‐2, laminin, collagen types I, III, IV, VII, mRNA expression for gelatinases and their inhibitors were also analyzed by reverse transcriptase polymerase chain reaction (RT‐PCR). In 14 of 19 patients there was a positivily in 92‐kDa protein expression in keratinocytes. The 92‐kDa gelatinase protein was also present in the upper dermis with prevalence around blood vessels. In 15 of 19 patients the 72‐kDa was localized in the upper dermis, almost exclusively in the papillary dermis but absent in epidermis. TIMP‐1 and TIMP‐2 were both negative in all eases in immunoperoxidase and RT‐PCR. Using RT‐PCR we show that the 72‐kDa mRNA is expressed exclusively in the dermis, on the contrary the 92‐kDa was present in epidermis and dermis. Type I, III, IV and VII collagens did not show any alteration or disruption. Overexpression and production of gelatinases without inhibitory effects suggest a role of these proteins in remodelling the psoriatic skin probably inducing the typical histological pattern of papillomatosis.