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Notes: Summary Despite the fact that several cell types residing in or travelling through the skin are targets and/or sources of nerve growth factor (NGF), little is known about the role of NGF in skin development, physiology and disease. Employing a previously defined skin organ culture assay for studying the proliferation of murine keratinocytes in their natural tissue environment, we have assessed the effect of murine NGF (7S) on keratinocyte proliferation in intact skin derived from two defined stages of the murine hair cycle. We found that 10–200 ng/ml NGF stimulated epidermal keratinocyte proliferation in organ-cultured C57 BL-6 mouse skin in the telogen phase of the hair cycle. Follicle keratinocyte proliferation was stimulated by 100 ng/ml NGF in telogen skin organ culture, but this concentration of NGF inhibited both epidermal and follicle keratinocyte proliferation in organ culture of anagen skin. The latter inhibitory effect of NGF was abrogated by co-incubation with neutralizing anti-NGF antibodies or with the protein kinase C inhibitor staurosporine. The proliferation-modulatory effects of NGF were associated with the induction of significant mast cell degranulation, and were inhibited by cromoglycate co-administration. This is the first report of a modulatory, hair cycle-dependent effect of NGF on keratinocyte proliferation in situ, which may require the presence of mast cells. Our study supports the notion of auto- and paracrine functions of NGF in murine skin physiology, which can be further assessed in the physiologically relevant mouse model delineated here.

Notes: Background  Cancer testis antigens (CTAs) are expressed in a variety of malignant tumours. No CTA expression is found in normal adult tissues, except in male germ cells and occasionally placenta. To date, more than 20 CTAs or antigen families have been identified.Objectives  Owing to their tumour-associated expression pattern, CTAs may be useful for making a distinction between benign and malignant neoplasms. The present study was done to analyse the value of CTAs for the discrimination of cutaneous melanoma and naevi.Patients and methods  Primary melanomas (38) and 19 naevi were analysed for their expression of CTAs by immunohistochemistry using the following monoclonal antibodies (mAb) to the following antigens (mAb/antigen): MA454/MAGE-A1, 57B/MAGE-A4, ES121/NY-ESO-1. In a subset of melanomas (n = 26), the CTA panel was extended to three additional CTAs (mAb/antigen): CT7-33/MAGE-C1, M3H67/MAGE-A3 and GAGE/GAGE.Results  All 19 naevi were negative for the mAbs MA454, M3H67, 57B, ES121, CT7-33 and GAGE. In melanoma, the immunoreactivity was as follows: MA454: 8/38 (21%), 57B 11/38 (29%), ES121 9/38 (24%). However, 19/38 (50%) were positive for at least one CTA. When 26 melanomas were tested for the expression of six different CTAs 20/26 (77%) were positive for at least one CTA.Conclusions  CTAs may be useful in the determination of suspected malignancy in cutaneous melanomas. The low incidence of particular CTAs can be overcome by increasing the number of CTAs analysed.

Notes: Background  Autoantibodies against the glycoproteins desmogleins 1 and 3 which are components of the desmosomal adhesion complex have been shown to be responsible for the loss of epidermal adhesion characteristic of pemphigus. Elimination of these antibodies should clinically improve the pathology of this group of severe autoimmune blistering skin disorders.Objectives  To gather information about the efficacy of immunoadsorption in the reduction of pathogenic serum autoantibodies against desmogleins 1 and 3 and to evaluate the clinical benefit of immunoadsorption in the treatment of pemphigus.Patients and methods  Nine patients with pemphigus and detectable circulating desmoglein antibodies were included in this open trial. Two immunoadsorption treatments separated by a 48-h interval were performed per patient. Anti-desmoglein 1 and 3 antibodies in the patients' sera were monitored by enzyme-linked immunosorbent assay and indirect immunofluorescence before and following each immunoadsorption. In addition, the efficacy of the tryptophan-linked polyvinylalcohol adsorber in removing antidesmoglein antibodies was directly evaluated.Results  IgG antibodies against desmogleins 1 and 3 were effectively eliminated from the patients' plasma upon passage through the adsorber and levels of serum autoantibodies were significantly reduced by immunoadsorption. A single immunoadsorption treatment led to a reduction of antidesmoglein autoantibodies of about 30%. Clinically, mucosal and cutaneous lesions improved allowing for a reduction of the systemic immunosuppressive treatment with glucocorticoids.Conclusions  Immunoadsorption with tryptophan-linked polyvinylalcohol adsorbers holds promise as a highly effective and safe adjuvant therapeutic regimen in pemphigus.

Notes: Background  Cutaneous T-cell lymphomas (CTCLs) are a heterogeneous group of skin neoplasms that originate from T lymphocytes. An anti-CTCL T-cell immunity has been described but seems to be inefficient to clear CTCL cells. It is not known whether cutaneous dendritic cells (DCs) perpetuate the proliferation of the malignant CTCL cell clone or play a role in the control of this usually slowly progressing disease.Objectives  To characterize CTCL cell properties in the control of anti-CTCL T cells and to pave the way for a DC-based immunotherapy for CTCL.Methods  We studied the interaction of a CTCL cell line with DCs and with allogeneic T cells.Results  We found an antigen non-specific capacity of viable but not apoptotic CTCL cells to hamper CD4+ and CD8+ T-cell proliferation in a dose-dependent manner, indicating a suppressive potential of CTCL cells. Both viable and apoptotic CTCL cells were phagocytosed by immature DCs but only apoptotic CTCL cells induced an upregulation of DC maturation markers to a degree which enabled classification of these DCs as semimature. CTCL cells did not respond with proliferation when encountering allogeneic, mature DCs either loaded with CTCL cell material or unloaded, indicating a role for DCs in the induction of anti-CTCL T-cell immunity rather than in perturbation of clonal proliferation. For the loading of DCs with CTCL material lysate seems to be optimal as apoptotic cells were not phagocytosed extensively and necrotic CTCL material induced a partial cellular toxicity in DCs. DCs loaded with CTCL material were cryopreservable without significant loss of DC viability, surface marker expression or allostimulatory activity.Conclusions  Together, these data argue in favour for a DC-based immunotherapy for CTCL patients and provide an experimental protocol for preparing CTCL cell-loaded DCs.

Notes: Summary Background  The existence of an effective antitumour immune response in mycosis fungoides (MF) has been shown by the isolation of tumour-specific T-cell clones from such patients. Dendritic cells (DCs) are considered crucial for the induction of immunity, including resistance to tumours. Apoptotic tumour cells are a major source for tumour antigens processed and presented by DCs via cross-presentation. The production of interleukin (IL)-10 by MF tumour cells is acknowledged and may block DCs maturation leading to tumour tolerance. Objectives  Cross-presentation of apoptotic tumour cells by DCs will induce immunity if the DCs mature, but tolerance if maturation does not occur. We now further characterize the DCs in skin infiltrates of patch/plaque-stage MF (PS) and tumour-stage MF (TS) in situ . Secondly, we demonstrate apoptosis in MF infiltrates in situ and analyse the association of apoptotic cells to immature DCs, mature DCs and IL-10-positive cells. Methods  Immunohistochemical staining (single, double, triple) employing novel markers specific for immature and mature DCs, IL-10 and a terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labelling (TUNEL) test were done on representative skin biopsies from PS and TS. Results  In PS, the immature DCs are mostly lag/langerin + Langerhans cells (LCs). In the epidermis of PS, LCs predominate over fully mature DCs (non-LC type, CD83+, DC-lamp+). In the dermis of PS and TS, equal numbers of mature and immature (CD1a+, CD1c+) DCs are densely interspersed between the lymphocytic infiltrate. In TS, immature DCs mostly lack lag or langerin expression. Immature DCs with incorporated apoptotic cells were found rarely in PS but increasingly in TS. By triple staining in situ we could now show that strongly IL-10+ cells frequently surround immature DCs, some of them with incorporated apoptotic cells. Conclusions  DCs in MF perform a dual role, namely induction and maintenance of antitumour immunity, or, under less favourable circumstances such as production of IL-10 downregulation of antitumour immunity. The latter condition was mainly seen in TS, possibly explaining disease progression. Further in vitro studies are now required illuminating the role of DCs for the antitumour immune response in MF.

Notes: Background  In inflamed skin, keratinocytes and inflammatory cells both produce large amounts of tumour necrosis factor (TNF) -α, a cytokine with broad effects that are relevant to inflammation. Blockade of this proinflammatory cytokine by a monoclonal anti-TNF-α antibody might be effectively used in the treatment of inflammatory skin diseases. Objectives  To gather information about the efficacy of an anti-TNF-α antibody (infliximab) in the treatment of skin lesions of psoriatic arthritis. Methods  Six patients with progressive joint disease and psoriatic skin lesions unresponsive to methotrexate therapy were treated with anti-TNF-α antibody. The Psoriasis Area and Severity Index was determined before and 10 weeks after initiation of therapy. Results  Improvement of psoriatic skin lesions was observed in all patients. In addition, a marked improvement of the joint disease was noted. Conclusions  Therapy with anti-TNF-α antibody may be an effective treatment regimen for both psoriatic arthritis and psoriatic skin lesions.