[Expression of cancer testis (CT) antigens in pediatric and adolescent melanomas]. / Expression von Cancer-Testis(CT)-Antigenen in Melanomen des Kindes- und Jugendalters.

BACKGROUND: One of the main problems in the diagnostics of pediatric melanomas is the differentiation from benign dermal lesions typical for this age group, such as Spitz nevus. The biological behavior of pediatric melanomas differs considerably from that of melanomas in adults. MATERIAL AND METHODS: Cancer testis (CT) antigens are named after their typical expression pattern since they are present in various types of malignant tumors but in normal adult tissues are solely expressed in testicular germ cells. Because of this tumor-associated expression pattern, CT antigens are regarded as potential targets for vaccine-based immunotherapy of cancer and might be used as diagnostic tools in surgical pathology. In adults, melanoma is among the tumors showing a high incidence of CT antigen expression; however, while there is ample knowledge about adult melanomas, little is known about the presence of CT antigens in pediatric melanomas. Consequently, the expression of CT antigens MAGE-A1, MAGE-A4, CT7/MAGE-C1, NY-ESO-1, and GAGE was analyzed in a series of pediatric melanomas. The study was restricted to cases of metastatic disease and/or fatal outcome. A total of 12 cases were available and immunohistochemically analyzed with monoclonal antibodies (mAb). RESULTS: The expression of CT antigens was generally low and present in only 4 of 12 cases. This is in stark contrast to the expression of these antigens in adult melanomas. Moreover, the extent of expression was very limited with most cases showing only a focal CT antigen expression and only marked in very small tumor areas (<5%). CONCLUSION: Despite the low case numbers this study indicates that CT antigens are most likely not useful as diagnostic markers in pediatric melanomas or as targets for vaccine-based immunotherapy. It supports the notion that pediatric melanomas show a different biological behavior than their adult counterparts.

Linear IgA dermatosis in an immunosuppressed patient after allogenic bone marrow transplantation.

Linear IgA dermatosis (LAD) is a well-recognized acquired subepidermal bullous autoimmune disease. LAD is characterized by clinical, histopathological and immunopathological findings. We report the case of a 38-year-old man who suffered from a chronic myeloic leukaemia. Although he received immunosuppressive therapy he developed LAD after an allogenic bone marrow transplantation. After diagnosis of LAD was established we started a successful systemic therapy with dapsone, while continuing the preliminary medication. Here we report for the first time on a possible relationship between LAD and bone marrow transplantation in an immunosuppressed patient.

[Treatment of methicillin-resistant Staphylococcus aureus (MRSA) as part of biosurgical management of a chronic leg ulcer]. / Therapie eines Methicillin-resistenten Staphylococcus aureus (MRSA) im Rahmen der Behandlung eines chronischen Ulkus mittels Biochirurgie.

Colonization with methicillin-resistant Staphylococcus aureus (MRSA) strains is an increasing problem in the treatment of wounds. Only a very limited repertoire of effective treatment strategies is available, especially for outpatient care. We successfully treated a chronic leg ulcer colonized with MRSA on an ambulatory basis, using larvae of the common greenbottle fly Lucilia sericata. Whereas the proteases secreted by Lucilia sericata may lead to efficient selective necrolysis, the phenylacetate and phenylacetataldehyde may exert antimicrobial effects. Treatment with Lucilia sericata represents an effective and inexpensive treatment strategy of chronic wounds, especially when colonized with MRSA Due to the low acceptance by patients and medical stuff, it is not often employed.

Self-administered topical 5% imiquimod for the treatment of common warts and molluscum contagiosum.

BACKGROUND: Despite numerous therapeutic options the treatment of common warts and molluscum contagiosum remains unsatisfactory for both patients and physicians. Imiquimod, a novel topical immune response modifier, has been successfully used for the treatment of external anogenital warts. OBJECTIVES: We aimed to evaluate the safety, tolerance and efficacy of imiquimod for the treatment of common cutaneous warts and mollusca that were resistant to previous therapeutic interventions. METHODS: Imiquimod 5% cream was self-applied by the patients to the warts or mollusca once daily for 5 days per week and left in place overnight. Assessment for response and the occurrence of side-effects was performed every 4 weeks until clinical cure or up to a maximum of 16 weeks. RESULTS: Twenty-eight of 50 (56%) patients with warts achieved a total clearance (n = 15; 30%) or a > 50% reduction in wart size (n = 13; 26%) after a mean treatment period of 9.2 weeks. Twelve of 15 (80%) patients with mollusca achieved a total clearance (n = 8; 53%) or a > 50% reduction in molluscum size (n = 4; 27%). There was no difference in response with regard to gender, human immunodeficiency virus serostatus or atopic predisposition. CONCLUSIONS: Patient-applied 5% imiquimod cream holds promise as an effective treatment of common warts and mollusca in a difficult-to-treat patient population.

The antipsoriatic agent dimethylfumarate immunomodulates T-cell cytokine secretion and inhibits cytokines of the psoriatic cytokine network.

Interactions between infiltrating T cells and keratinocytes via the secretion of the TH1 cytokines interleukin (IL) 2 and interferon gamma (INF-gamma), the keratinocyte growth factor transforming growth factor alpha (TGF-alpha) and the cytokines IL-6 and IL-8 are thought to be the predominant mechanisms inducing skin lesions in psoriatic patients. Systemic treatment of psoriasis with fumaric acid derivatives (FAEs) has been reported to be effective in the treatment of psoriasis, but the mode of action is still unknown. To clarify this phenomenon, keratinocytes from psoriatic patients as well as from healthy volunteers were mono- and cocultured with HUT 78 T cells with/without the addition of FAEs; the cytokine concentrations were then measured in the culture supernatants. Furthermore, mRNA expression was determined in epidermal growth factor (EGF) -activated keratinocytes as well as in phytohaemagglutinin (PHA)-activated HUT 78 T cells. Only dimethylfumarate (DMF) diminished IL-6 and TGF-alpha secretion in the psoriatic cocultures. However, it did not have this effect on cocultures from control subjects or on monocultures. DMF suppresses EGF-induced TGF-alpha mRNA induction in psoriatic keratinocytes. DMF inhibited INF-gamma secretion in all cultures but stimulated the IL-10 secretion. This immunomodulation away from the TH1 cytokine IFN-gamma to the TH2 cytokine IL-10 was confirmed in HUT 78 T cells by Northern blot analysis. An increased number of eosinophils is a known side-effect in patients treated with this drug, suggesting a clinical relevance of this immunomodulation in vivo. This immunomodulation and the suppression of cytokines from the psoriatic cytokine network could be responsible for the beneficial effect of DMF in the treatment of a hyperproliferative and TH1 cytokine-mediated skin disease.

Immune response against human primary malignant melanoma: a distinct cytokine mRNA profile associated with spontaneous regression.

Spontaneous regression of melanoma lesions is thought to be the result of an efficient immune response against melanoma cells in vivo. The outcome of immune responses is critically influenced by a complex network of interacting cytokines present in the local microenvironment. Analysis of cytokine gene transcription in melanoma lesions exhibiting or lacking a sufficient anti-tumor immune response thus may help to define cytokines or cytokine combinations critical to the development of this immune response. In the present study, we have investigated an extended panel of cytokine and cytokine receptor genes by reverse transcription-PCR and in situ hybridization in regressive and progressive primary human cutaneous melanoma samples. Whereas the presence of a lymphocyte infiltrate in tissue samples was associated with a TH1 cytokine mRNA profile (TNF-alpha, INF-gamma, IL12p35, IL12p40, IL2Rbeta, and IL2Rgamma), clinically and histologically regressive samples exhibited additionally increased transcript levels for GM-CSF, IL2, and IL15. mRNAs of TH2 cytokines IL4 and IL5 were detected only in a minor portion of progressive melanoma samples and regressive melanoma lesions. These results were further supported by comparison of progressive with regressive regions in three melanoma samples. Again, regressive regions contained higher transcript levels for GM-CSF, IL2, and IL15. In comparison to cutaneous metastatic melanoma lesions, regressive melanomas also overexpressed the same cytokine mRNA profile. These results provide evidence for an association of spontaneous regression with increased transcript levels for the cytokine combination GM-CSF, IL2, and IL15 in malignant melanoma. This cytokine combination could be relevant for experimental anti-tumor immune response studies and for immunotherapeutic and gene transfer studies in the treatment of melanoma patients.

Analysis of Pmel17/gp100 expression in primary human tissue specimens: implications for melanoma immuno- and gene-therapy.

Pmel17/gp100-encoded tumor-associated antigens are recognized by cytotoxic T lymphocytes in melanoma patients and may represent attractive target antigens for immuno- and gene-therapeutic strategies. An important prerequisite for identification and monitoring of melanoma patients that could potentially benefit from Pmel17/gp100-based immuno- and gene-therapies is the detailed knowledge of Pmel17/gp100 expression in vivo. Immunophenotyping is considerably hampered by the different immunoreactivities of Pmel17/gp100-reactive antibodies. Therefore, we analyzed an extended series of different primary normal and malignant human tumor specimens for Pmel17/gp100 expression at the mRNA level. Transcripts were detectable in all malignant melanoma tissue specimens representing all stages of tumor progression, with significant levels even in early and amelanotic melanoma lesions. In contrast, normal melanocytes exhibited significantly less Pmel17/gp100 mRNA in vivo, as determined by comparative in situ hybridization. Tissue specimens from the retina and substantia nigra also contained Pmel17/gp100 mRNA, whereas other normal and malignant human tissues were negative. As determined by comparative in situ hybridisation and HMB-45 immunostaining, even tumor tissue lacking Pmel17/gp100 immunoreactivity contained Pmel17/gp100 transcripts. Our results indicate a melanocytic-cell-lineage-restricted expression of Pmel17/gp100 with significant transcript levels in all stages of melanoma progression, including early and amelanotic melanoma lesions, and a significantly differential expression between melanoma cells and normal melanocytes in vivo. Owing to its higher sensitivity, phenotyping of individual tumor specimens by mRNA expression analysis seems to be more valuable than phenotyping by immunostaining.

Tyrosine phosphorylation in psoriatic T cells is modulated by drugs that induce or improve psoriasis.

BACKGROUND: The induction of protein tyrosine kinases (PTKs) is known to be a key element in the activation of lymphocytes. OBJECTIVE: Because immunologic mechanisms are important in the pathogenesis of psoriasis, we examined the time course of tyrosine-phosphorylated proteins (p-tyr) as a marker for cellular PTK activity in phytohemagglutinin (PHA)-stimulated T cells of psoriatic patients and healthy controls. METHODS AND RESULTS: PHA-stimulated T cells from both groups expressed peaks of p-tyr after 15 min and 4 h. In T cells from psoriatics, the 15-min peak was smaller but the 4-hour peak reached an enormous maximum, which was 270% higher than the basic p-tyr value. PHA-stimulated T cells were additionally treated with psoriasis-provoking drugs (lithium, chloroquine, propranolol and ethanol) and the two immunosuppressive drugs cyclosporin A and FK 506. Lithium and propranolol were able to increase the p-tyr level after 15 min in PHA-stimulated T cells from psoriatics in contrast to controls. Chloroquine and ethanol did not have a significant effect on T cells of both groups. CsA markedly diminished the phosphorylation of intracellular tyrosines in T cells of psoriatics and controls, whereas FK 506 diminished the p-tyr level in controls only slightly. CONCLUSION: We have characterized important differences in p-tyr phosphorylation activities of psoriatic T cells compared to controls. This could be a hint to explain the known abnormalities of psoriatic T cells.

Cyclosporin A, FK506 and dithranol after tyrosine-specific protein phosphorylation in HaCaT keratinocytes.

Protein tyrosine kinases (PTKs) are closely related to cell growth, proliferation and differentiation. In keratinocytes, various growth factor receptors and cytosolic proteins, including the EGF and IGF receptors, the proteins of the src family and others, exhibit PTK activity. In psoriatic epidermis an increased level of EGF receptors and their ligand TGF-alpha has been found, and this is thought to be one reason for the pathological hyperproliferation of keratinocytes in this disease. Oral treatment with cyclosporin A (CsA) and FK506 or topical treatment with dithranol lead to an improvement in psoriasis. In the present study we examined the effect of these three drugs on the cellular content of phosphorylated tyrosines in highly proliferative HaCaT keratinocytes. HaCaT keratinocytes can be used as a model for highly proliferative epidermis, e.g. psoriatic epidermis. CsA had no effect whereas FK506 and dithranol reduced the phosphorylation of tyrosine residues in HaCaT keratinocytes. The activation of serine/threonine protein kinase C (PKC) is known to downregulate PTKs. Therefore we incubated keratinocytes with the selective PKC inhibitor Ro 31-8220 in addition to the other drugs. Only after the addition of Ro 31-8220 to FK506-treated keratinocytes was the phosphotyrosine (p-tyr) level elevated, but this was only one-third of the increase measured without additional therapeutic drugs. We assume that an induction of PKC alone is not responsible for the reduced p-tyr level after treatment with dithranol and FK506.(ABSTRACT TRUNCATED AT 250 WORDS)

Chloroquine stimulates the mitogen-driven lymphocyte proliferation in patients with psoriasis.

Chloroquine is known to exacerbate psoriasis. Since immunological stimuli are considered to be important for the pathogenesis of psoriasis, we compared the effects of chloroquine on cell-mediated immunity in 15 healthy control individuals and 15 patients with psoriasis. We employed the spontaneous and phytohemagglutin (PHA)-induced uptake of 3H-thymidine to measure lymphocyte proliferation. Chloroquine was added to the cultures at concentrations ranging from 0.022 to 220 microM. We found that both spontaneous and PHA-driven lymphocyte proliferations were significantly lower in patients with psoriasis (p < 0.002). The spontaneous blastogenesis in both controls and patients remained stable under chloroquine. In PHA-driven cultures in controls, 0.022-2.2 microM chloroquine had no effect, higher concentrations of the drug suppressed proliferation. In patients, 22 microM chloroquine surmounted the suppression of the PHA-induced proliferative response found in controls; moreover, 2.2-0.022 microM chloroquine increased lymphocyte proliferation by > 300% (p < 0.002). Our data indicate that in psoriasis the lower lymphocyte transformation is abnormally stimulated by the addition of pharmacological doses of chloroquine.