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Please cite this paper as: Enhanced T-cell activation by immature dendritic cells loaded with HSP70-expressing heat-killed melanoma cells. Experimental Dermatology 2010; 19: 108–116. Vaccination protocols that utilize dendritic cells (DCs) to elicit therapeutic immunity against tumors are the subject of intense research. Given that the capacity of DCs to cross-present antigens is physiologically low, there is considerable interest to develop strategies that enhance that pathway. In order to best exploit the enhanced cross-presentation of antigens bound to heat shock protein 70 (HSP70), we analysed melanoma cell preparations for their HSP70 expression. Western blotting revealed strong upregulation of HSP70 after heat-killing in contrast to UV-B irradiation. When the uptake of heat-killed necrotic cells by DCs at various levels of maturation was assessed, 61 ± 7% of immature DCs (iDCs) internalized fluorescence-labelled necrotic material. Apoptotic material from UV-B-irradiated cells was internalized by only 48 ± 5% of iDCs. Maturation-inducing cytokines did not affect the uptake when added simultaneously with the tumor cell preparations. Loading DCs with heat-necrotic or apoptotic melanoma cells slightly reduced CD83 expression while leaving CD208 (DC-LAMP) expression unchanged. As determined by IFN-γ-detecting enzyme-linked-immunospot assays, iDCs loaded with heat-killed melanoma cells activated autologous T cells most effectively when used without any further maturation, whereas DCs loaded with apoptotic material required maturation. In conclusion, HSP70-expressing melanoma cells could be generated by heat-killing. Loading iDCs with heat-killed melanoma cells resulted in a superior priming of autologous T cells in vitro. [ABSTRACT FROM AUTHOR]

Abstract: Background: Breath analysis could offer a non-invasive means of drug monitoring if adequate analytical methods and robust correlations between drug concentrations in breath and blood can be established. We therefore applied headspace solid-phase microextraction coupled with gas chromatography–mass spectrometry (HS-SPME–GC–MS) to assess breath and blood concentrations of the intravenous drug propofol in patients under anesthesia or sedation. Methods: Arterial, central- and peripheral-venous blood and alveolar breath samples were drawn in parallel from 16 mechanically ventilated patients. In addition, six patients undergoing lung resection were investigated. Substances were preconcentrated by means of HS-SPME, separated by GC and identified by MS. Results: Propofol detection limits were 0.006 nmol/L in breath and 72.20 nmol/L in blood, the quantitation limits were 0.009 nmol/L and 75.89 nmol/L (end tidal breath/blood). Intraday precision was 8–11%, recovery 97–103%. Propofol concentrations were 0.04–0.5 nmol/L in breath and 2–120 μmol/L in blood. Only arterial propofol concentrations showed a correlation with concentrations in breath. Impaired ventilation/perfusion ratios in patients under lung resection resulted in changes of correlation coefficients. Conclusions: Reliable and precise analytical methods such as HS-SPME–GC–MS represent basic requirements if breath analysis is to be set up for non-invasive monitoring of intravenous drugs and control of anesthesia. [Copyright &y& Elsevier]

Dendritic cells (DCs) have become popular candidates in cancer vaccination because of their crucial role in inducing T-cell responses. However, clinical studies greatly differ in their protocols for generating DCs and the efficacy in treating established tumors needs to be improved. We systematically analyzed DCs maturated by five different protocols for surface markers, the alloproliferative T-cell response, the DC survival after cytokine deprivation, the stability of surface markers under the influence of interleukin-10 (IL-10) and the DC cytokine secretion pattern. Monocyte-derived DCs were maturated by CD40-ligand (CD40-L), unmethylated cytosine–guanosine dinucleotides-oligodinucleotides (CpG-ODN), an inflammatory cytokine cocktail (ICC), a combination of ICC and CD40-L, or ICC, CD40-L and CpG-ODN. A high co-expression of DC maturation and costimulation markers was found after treatment with ICC plus CD40-L (69.3 ± 9.6% CD83/CD80 double positive staining) and correlated with a significantly increased cell survival, a high expression of the antiapoptotic factor bcl-XL, a stable CD83high/CD14low expression under the influence of IL-10, and a strong alloproliferative T-cell response. In conclusion, our data support the use of maturation protocols containing ICC plus CD40-L in order to generate highly mature, phenotypically stable, cell-death resistant, and T-cell stimulatory DCs for clinical application in cancer patients. [ABSTRACT FROM AUTHOR]

We analyzed the value of digital epiluminescence microscopy (DELM) for the long-term follow-up of atypical nevi. Patients (n=530) were prospectively categorized into defined melanoma risk groups and followed by clinical and epiluminescence microscopy (ELM) examinations. Atypical nevi (n=7001) were additionally followed by DELM. During follow-up (median 32.2 months), we detected 53 melanomas among 637 excised lesions (8.3% overall chance of success). The chance of success for melanoma detection among lesions suspicious by ELM criteria was increased to 17% when additional DELM-documented changes were present. Moreover, 18 of the 53 melanomas were exclusively identified by DELM-documented changes, indicating that DELM increased the sensitivity of the ELM analysis by identifying additional melanomas. However, for lesions exclusively excised due to DELM changes, the chance of success was lower than for ELM (5.2 vs 11.8%). Excisions due to mere DELM changes detected 66.7% of melanomas in familial atypical mole and multiple melanoma (FAMMM) and 32.5% of melanomas in atypical mole syndrome (AMS) patients. We conclude that DELM is a valuable tool for the long-term follow-up of atypical nevi, especially in the high-risk groups of FAMMM and AMS patients. Randomized controlled trials are needed to validate the data from this clinical trial.Journal of Investigative Dermatology (2006) 126, 980–985. doi:10.1038/sj.jid.5700119; published online 2 March 2006 [ABSTRACT FROM AUTHOR]

Dieckhoff K, Graf P, Beinhauer B, Schwaerzler C, Carballido JM, Neumann C, Zachmann K, Jung T. Deficient translocation of c-Rel is associated with impaired Th1 cytokine production in T cells from atopic dermatitis patients.Decreased production of T helper type 1 (Th1) cytokines, such as interferon-γ (IFN-γ) or interleukin-2 (IL-2), is a hallmark of atopic diseases. While accessory signals from antigen-presenting cells may be missing, T cells themselves may be suppressed in their ability to produce substantial amounts of Th1 cytokines. We show, in this study, that T cell receptor (TCR)-activated T cells from atopic dermatitis (AD) patients proliferate less than control T cells and produce lower amounts of IFN-γ and IL-2, but comparable amounts of IL-4. Because mice lacking the nuclear factor kappa B (NF-κB) transcription factors– p65 or c-Rel– show reduced Th1, but undisturbed Th2 responses, we investigated the role of c-Rel and p65 for Th1 cytokine production in T cells from healthy and severe AD patients. TCR-activated primary T cells from healthy donors treated with c-Rel antisense oligonucleotides produced lower levels of IL-2 and IFN-γ and proliferated less efficiently than the corresponding control T cells. Moreover, transfection of primary T cells with c-Rel or p65 enhanced proliferation and production of IL-2 and IFN-γ. Nuclear extracts of activated primary T cells from AD donors bound weakly to NF-κB-specific oligonucleotides, compared to extracts from healthy control T cells. Western blotting studies revealed that nuclear, but not cytosolic, extracts from T cells of AD patients lacked significant amounts of c-Rel and p65. T cell clones derived from AD patients failed to sufficiently translocate c-Rel and p65 into the nucleus following activation. Thus, impaired nuclear translocation of c-Rel and p65 may determine an impaired Th1 cytokine response in AD. [ABSTRACT FROM AUTHOR]

Reich K, Hugo S, Middel P, Blaschke V, Heine A, Neumann C. The maturation-dependent production of interleukin-16 is impaired in monocyte-derived dendritic cells from atopic dermatitis patients but is restored by inflammatory cytokines TNF-α and IL-1β.Maturation of dendritic cells (DCs) influences important DC functions such as production of cytokines. Recently, DCs were identified as a source of interleukin-16 (IL-16), a chemotactic factor for DCs themselves, CD4+ T cells, and eosinophils. There is evidence that DC-derived IL-16 may contribute to the pathogenesis of atopic dermatitis (AD).To investigate the production of IL-16 during differentiation of monocytes into DCs in healthy individuals and patients with AD.IL-16 production was investigated by quantitative real-time RT-PCR, intracellular cytokine staining, immunoblotting, and ELISA.DCs generated from peripheral monocytes by 5-day culture in the presence of IL-4 and granulocyte/macrophage colony-stimulating factor acquired the capability to synthesize, store, and secrete IL-16. Storage and release of IL-16 was further enhanced during final DC maturation induced by additional 3-day culture with tumor necrosis factor-α (TNF-α) and monocyte-conditioned medium. Maturation, as determined by up-regulation of CD83 and CD86 surface expression, and production of IL-16, but not production of IL-10 and IL-12p40 was impaired in day 8 DCs derived from AD patients compared to those from healthy donors. Stimulation of day 8 DCs from AD patients with TNF-α and IL-1β enhanced the expression of CD83 and CD86 and restored the production of IL-16.Signals involved in the activation and maturation of DCs enhance their capacity to produce IL-16. Functional abnormalities present in patients with AD at the monocyte level may account for impaired maturation and IL-16 production of monocyte-derived DCs. [ABSTRACT FROM AUTHOR]

Lippert U, Zachmann K, Henz BM, Neumann C. Human T lymphocytes and mast cells differentially express and regulate extra- and intracellular CXCR1 and CXCR2. CXCL8 plays a major role in cell recruitment to sites of inflammation. Apart from neutrophils, little is known, however, about the cellular distribution and regulation of CXCL8 receptors in cells involved in acquired and adaptive immune responses. In previous studies, we have demonstrated the extracellular expression and function of CXCR1/2 on mast cells and also detected an intracellular pool of CXCR1/2. Here, we have addressed the question of receptor regulation during stimulation of human mast cells (HMC-1 cell line) and have studied T cells in comparison. Cell permeabilization was performed to detect both surface and possible intracellular receptor pools. HMC-1 cells stained positive for both receptors on the cell surface (CXCR1, 50%; CXCR2, 51%) and also after cell permeabilization (CXCR1, 86%; CXCR2, 74%). Similarly, T cells exhibited both cell-surface receptor expression (CXCR1, 30%; CXCR2, 23%) and higher total receptor expression (CXCR1, 50%; CXCR2, 36%), although overall values were lower than that in HMC-1 cells. On immunoblot, molecular weights of extra- and intracellular receptors on mast cells were the same, excluding altered receptor glycosylation. On stimulation with phorbol 12-myristate 13-acetate plus calcium ionophore, a time-dependent decrease of surface-membrane receptors was observed in both cell types, while total receptor remained the same, suggesting that receptor shedding is not involved. The kinetics of membrane receptor internalization and replenishment differed for the two cell types. Furthermore, receptor internalization was associated with decreased F-actin polymerization, a basic prerequisite for cell migration. These findings demonstrate for the first time the expression of extra- and intracellular CXCR1/2 receptors on T cells and delineate the dynamics of CXCR1/2 receptors on mast cells and T cells. Furthermore, they suggest a cell-type-specific and finely tuned regulation of chemokine responses at the receptor level in the context of inflammation. [ABSTRACT FROM AUTHOR]

The three peroxisome proliferator-activated receptor (PPAR) subtypes α, δ (β), and γ belong to the group of nuclear receptors that act as ligand-activated transcription factors. Recently, expression of PPARα and γ in keratinocytes has been demonstrated, and ligands of PPARα and γ have been found to enhance epidermal maturation and protect against cutaneous inflammation. There is evidence for a possible role of PPARs in psoriasis, as the expression of PPARα and γ is decreased in lesional skin and treatment with PPARγ agonists improves psoriatic keratinocyte pathology in vitro and in vivo. We performed a case-control study to search for possible associations between variations in the genes encoding PPARα and γ and psoriasis. Seven variations in these genes were analyzed in 192 patients with chronic plaque-type psoriasis and 330 healthy controls by PCR-based methods. No association between any of the investigated PPAR variants and psoriasis was found. Our findings argue against a significant contribution of the investigated PPAR variations to the genetic basis of psoriasis. [ABSTRACT FROM AUTHOR]

The diagnostic and prognostic importance of recurrent chromosomal aberrations in systemic B cell lymphoma is well documented. In contrast, limited data exist on genetic changes in primary cutaneous B cell lymphoma. In this study we investigated chromosomal aberration patterns in two types of primary cutaneous B cell lymphoma with a different clinical behavior. Twenty-two primary cutaneous B cell lymphomas, including nine follicle center cell lymphomas and 13 large B cell lymphomas of the leg, were analyzed by comparative genomic hybridization and in part by fluorescence in situ hybridization. The most frequent imbalances detectable were gains in 18q (eight of 22), 1q (six of 22), 7 (six of 22), 12q (six of 22), or Xp (four of 22), and losses in 6q (four of 22). In contrast to large B cell lymphomas of the leg, primary cutaneous follicle center cell lymphomas had fewer imbalances and lacked translocations affecting the IGH locus. Gains in 18q (eight of 13) and losses in 6q (four of 13) as well as breakpoints within the IGH locus (six of 11) were restricted to the large B cell lymphomas of the leg subtype. Translocation t(14; 18) was excluded in 16 primary cutaneous B cell lymphomas of both subtypes that were studied by fluorescence in situ hybridization. These results suggest that primary cutaneous follicle center cell lymphoma and large B cell lymphoma of the leg are characterized by different chromosomal aberration patterns, which in part might determine the different clinical course of these malignancies. [ABSTRACT FROM AUTHOR]

Peroxisome proliferator-activated receptor γ is a member of the nuclear receptor superfamily involved in adipocyte differentiation and glucose homeostasis. There is evidence that peroxisome proliferator-activated receptor γ may also act as a tumor suppressor. Here, we demonstrate expression of peroxisome proliferator-activated receptor γ in benign melanocytic naevi, different variants of primary cutaneous melanomas, and melanoma metastases. Peroxisome proliferator-activated receptor γ protein and peroxisome proliferator-activated receptor γ1 mRNA were also detected in human melanoma cell lines. The peroxisome proliferator-activated receptor γ specific agonists 15-deoxy-Δ12,14 -prostaglandin J2 , troglitazone, and rosiglitazone dose-dependently inhibited cell proliferation in four melanoma cell lines, whereas a specific agonist of peroxisome proliferator-activated receptor α had no such effect. At a concentration of 50 µM rosiglitazone, the most potent peroxisome proliferator-activated receptor γ agonist tested suppressed cell growth by approximately 90%. Apoptosis could be induced in melanoma cell lines by incubation with tumor-necrosis-factor-related apoptosis-inducing ligand. In contrast, the growth inhibitory effect of peroxisome proliferator-activated receptor γ activation was independent of apoptosis and seemed to occur primarily through induction of cell cycle arrest. Our data indicate that melanoma cell growth may be modulated through peroxisome proliferator-activated receptor γ. [ABSTRACT FROM AUTHOR]

The psoriatic inflammatory process is characterized by an overexpression of pro-inflammatory cytokines such as tumor necrosis factor-α and interleukin-1β compared with a relative deficiency of anti-inflammatory factors such as interleukin-10 and the interleukin-1 receptor antagonist (interleukin-1Ra). Gene polymorphisms that affect cytokine production may contribute to the disease-associated cytokine imbalance and influence susceptibility to psoriasis. Here, we investigated the relationship between polymorphisms in the genes encoding for tumor necrosis factor-α (G-238A, G-308A), interleukin-1β (C-511T, T+3953C), and interleukin-1Ra (intron 2), and cytokine production in peripheral blood mononuclear cells of healthy donors, and analyzed the distribution of these polymorphisms in patients with psoriasis vulgaris (n = 231) and healthy controls (n = 345). Carriage of tumor necrosis factor A-238 allele 2 (–238*A) was associated with increased production of tumor necrosis factor-α in response to lipopolysaccharide in vitro , and with early onset disease (< 40 y), especially in male patients with psoriasis [32% vs 7% in male controls; odds ratio = 6.78, 95% confidence interval = (3.18–15.15), padjusted = 2 × 10-7 ]. Carriage of the interleukin-1B-511*1 (–511*C) homozygous genotype was associated with increased production of interleukin-1Ra in response to lipopolysaccharide and interleukin-10, and with late onset psoriasis [≥ 40 y; 61% vs 44% in controls; odds ratio = 2.04, 95% confidence interval = (1.19–3.53), padjusted = 0.0419]. These findings indicate that gene polymorphisms associated with altered cytokine responses in vitro may modify age of onset of psoriasis. They also provide further evidence that patients with early and late onset psoriasis differ in their genetic background. [ABSTRACT FROM AUTHOR]

Summary Psoriasis is a chronic inflammatory skin disease in which epidermal hyperplasia results from the release of cytokines by infiltrating type 1 T cells. Up- regulation of endogenous interleukin-10 controls type 1 skin responses in animal models; however, interleukin-10 production is low in psoriatic lesions. Consistent with an important role of interleukin-10 in psoriasis, we and colleagues have recently demonstrated clinical efficacy of subcutaneous administration of recombinant interleukin-10 to affected patients. Here, we studied the effects of interleukin-10 on disease-related inflammatory pathways. Patients were treated with recombinant interleukin-10 over 6 wk in an open-label phase II clinical trial. Tissue was obtained before and after therapy and examined by histology/immunohistochemistry, in situ hybridization, and quantitative real-time reverse transcription–polymerase chain reaction. Ten of 14 patients showed a marked reduction of the clinical disease activity. The clinical response was associated with a significant decrease of cutaneous T cell infiltration and the lesional expression of type 1 cytokines interferon-γ and tumor necrosis factor-α. Interleukin-10 inhibited the epidermal interleukin-8 pathway by downregulating the expression of interleukin-8, its receptor CXCR2, and its inducer interleukin-17, and partially reversed the aberrant keratinocyte maturation defining psoriatic epidermal pathology. Remarkably, there was evidence that genetic factors are involved in the response to interleukin-10 as individual variations in the downregulation of tumor necrosis factor-α were related to the presence of polymorphisms in the tumor necrosis factor-α promoter. These data suggest that excessive production of type 1 cytokines in human skin disease can be counter-regulated by the administration of recombinant interleukin-10. Genotypic analysis may help to identify patients that will preferentially respond to interleukin-10 therapy. [ABSTRACT FROM AUTHOR]