Skin cancer in organ transplant recipients: dynamics in the incidence and clinical predictors for the first and subsequent post-transplant non-melanoma skin cancer.

BACKGROUND: Risk factors for primary non-melanoma skin cancer (NMSC) in organ transplant recipients (OTR) have been well described. Data for subsequent NMSC and dynamics in their occurrence in OTR are limited. OBJECTIVE: To study long-term risks of primary and subsequent NMSC and associated risk factors in OTR. METHODS: A retrospective single-centre cohort study analysing medical records from a dermato-oncological specialty clinic. RESULTS: Of 464 OTR 110 (23.7%) developed at least one, 73 (15.7%) two and 51 (11%) three NMSC during a median follow-up of 9.6 years. Cumulative incidences at 5, 10 and 15 years were 14.7%, 23.5% and 34.5% for the first and 75.8%, 86.5% and 93.3% for the second. Median time-to-diagnosis declined from 22 years (95% CI 19-25) to 2 years (1-3) and about 1 year (0-2) for the first, second and third NMSC. Risk for subsequent NMSC only partially related to risk factors for the primary NMSC. Histologic type of the first NMSC predicted subtype and time-to-diagnosis of the subsequent NMSC. CONCLUSIONS: A first post-transplant NMSC, particularly a SCC, confers a high risk for subsequent NMSC arising with accelerated dynamics. Risk-adapted dermato-oncologic surveillance is advisable for all OTR.

Dimethyl fumarate modulates neutrophil extracellular trap formation in a glutathione- and superoxide-dependent manner.

BACKGROUND: Neutrophil (polymorphonuclear) granulocytes (PMN) have been shown to contribute to the pathogenesis of psoriasis by releasing interleukin-17 and LL37-DNA complexes via neutrophil extracellular traps (NETs), webs of chromatin strands decorated with antimicrobial peptides, in psoriatic skin. Fumaderm® , a fumaric acid ester (FAE) formulation consisting of different FAE salts, has been successfully used to treat psoriasis for decades. Most recently, FAE treatment was reported to inhibit NET formation in murine epidermolysis bullosa acquisita. OBJECTIVES: To elucidate the effect of FAE treatment on human psoriasis and healthy donor NET formation. RESULTS: Among the compounds present in the FAE formulation, dimethyl fumarate (DMF) pretreatment of human psoriasis and healthy donor PMN resulted in a consistent inhibitory effect on NET formation in response to phorbol 12-myristate 13-acetate but not to platelet activating factor and ionomycin. This effect was l-glutathione (GSH) dependent and involved a decrease in reactive oxygen species (ROS) production, a key event in NET formation. In contrast, G-protein-coupled signalling and protein synthesis were not involved. Monomethyl fumarate (MMF) was found to slightly reduce ROS production without affecting NET formation. CONCLUSIONS: We report DMF as a potent, stimulus-specific, GSH- and ROS-dependent modulator of NET formation. Our results support the notion that modulation of NET formation contributes to the beneficial effects of FAEs in a variety of inflammatory conditions.

Altered density, composition and microanatomical distribution of infiltrating immune cells in cutaneous squamous cell carcinoma of organ transplant recipients.

BACKGROUND: The inflammatory tumour microenvironment is crucial for effective tumour control, and long-term immunosuppression has been identified as a major risk factor for skin carcinogenesis. In solid organ transplant recipients (OTRs) undergoing long-term pharmacological immunosuppression, an increased incidence of cutaneous squamous cell carcinoma (SCC) and more aggressive tumour growth compared with immunocompetent patients has been reported. OBJECTIVES: To determine the density and phenotype of immune cells infiltrating SCC and surrounding skin in OTRs, and to characterize the microanatomical distribution patterns in comparison with immunocompetent patients. METHODS: We analysed immune cell infiltrates within SCC and at defined regions of interest (ROIs) of tumour-surrounding skin in formalin-fixed paraffin-embedded tissue of 20 renal transplant patients and 18 carefully matched immunocompetent patients by high-resolution semiautomated microscopy on complete tissue sections stained for CD4, CD8, CD20 and CD68. RESULTS: The overall immune cell density of SCC arising in OTRs was significantly reduced compared with immunocompetent patients. Particularly CD4+ infiltrates at the directly invasive margin and tumour vicinity, intratumoral CD8+ T-cell densities and the overall density of CD20+ tumour-infiltrating B cells were significantly reduced in the tissue of OTRs. CONCLUSIONS: Immune cell infiltrates within SCC and at defined ROIs of tumour-surrounding skin in OTRs differ markedly in their composition and microanatomical distribution compared with tumours arising in immunocompetent patients. Our findings substantially broaden the understanding of how long-term systemic immunosuppression modulates the local inflammatory microenvironment in the skin and at the site of invasive SCC.

At first sight or second glance: clinical presentation of mosaic manifestations of autosomal dominant skin disorders - a case series.

BACKGROUND: Several autosomal dominant disorders may manifest in mosaic patterns with cutaneous involvement. Genomic mosaicism results from postzygotic autosomal mutations, giving rise to clonal proliferation of two genetically distinct cell groups, which clinically present as lesions following the lines of Blaschko. OBJECTIVE: To increase the awareness of the clinical variability of mosaic manifestations in autosomal dominant skin disorders in order to avoid delayed diagnosis. METHODS: Clinicopathologic correlation in a case series including three patients with mosaic manifestations of different autosomal dominant skin diseases. RESULTS: Here, we describe a patient with type 1 segmental mosaicism of epidermolytic ichthyosis (case 1) and two patients with either type 1 (case 2) or type 2 (case 3) segmental neurofibromatosis 1 (NF1). CONCLUSION: Dermatologists should be familiar with mosaic manifestations of autosomal dominant skin diseases to ensure appropriate guidance of the affected patient. Genetic counselling is mandatory as even limited forms of mosaicism may involve the patient's germline with a moderately increased risk to transmit the mutation to their offspring, resulting in a more severe, generalized form of the respective disease.

Retrospective analysis evaluating the effect of a keratolytic and physical pretreatment with salicylic acid, urea and curettage on the efficacy and safety of photodynamic therapy of actinic keratoses with methylaminolaevulinate.

BACKGROUND: Photodynamic therapy (PDT) is a highly effective treatment option for actinic keratosis (AK). Hyperkeratosis of the AK impairs penetration of the photosensitizer and light and leads to a reduced efficacy of PDT. Therefore, it is commonly recommended to perform curettage of the AK prior to treatment. OBJECTIVE: This observational, monocentric, retrospective study sets out to compare the effects of curettage (CUR), chemical keratolytic pretreatment with salicylic acid 10% (SA), and urea cream 40% (UR) on the efficacy and tolerability of PDT. METHOD: A total of 44 subjects aged 73.2 ± 7.7 years (mean ± SD) with multiple AKs (mean 11.1 per patient) in face and scalp were analysed. In 15 patients, CUR was performed prior to PDT while 15 and 14 patients underwent keratolytic pretreatment with SA and UR, respectively, 1 day prior to PDT. All patients underwent one session of methylaminolaevulinate (MAL) PDT using a 630-nm LED lamp at 37 J/cm(2) , pain was measured using a visual analogue scale. The response rate was calculated using the documented number of AKs prior and 4 weeks after PDT. RESULTS: Mean lesion response rates were 68.5%, 61.4% and 60.8% for CUR, SA and UR respectively. Differences were not significant. Patients with SA or UR experienced significantly more pain (SA: 6.3 ± 2.7, P = 0.02; UR: 6.1 ± 1.8, P = 0.04) than patients with curettage (4.4 ± 2.1). The cosmetic result and the patients' satisfaction 4 weeks after PDT were good to excellent in all three groups without a significant difference. However, pretreatment with SA or UR led to pronounced local reactions compared to CUR. CONCLUSION: Keratolytic therapy with SA or UR is an effective pretreatment for PDT. However, it leads to an increase in pain during PDT and pronounced local reactions.

European Guidelines (S1) on the use of high-dose intravenous immunoglobulin in dermatology.

BACKGROUND: The treatment of severe dermatological autoimmune diseases and toxic epidermal necrolysis (TEN) with high-dose intravenous immunoglobulin (IVIg) is a well-established procedure in dermatology. As treatment with IVIg is usually considered for rare clinical entities or severe clinical cases, the use of immunoglobulin is not generally based on data from randomized controlled trials that are usually required for the practice of evidence-based medicine. Owing to the rarity of the indications for the use of IVIg, it is also unlikely that such studies will be available in the foreseeable future. Because the high costs of IVIg treatment also limit its first-line use, the first clinical guidelines on its use in dermatological conditions were established in 2008 and renewed in 2011. MATERIALS AND METHODS: The European guidelines presented here were prepared by a panel of experts nominated by the EDF and the EADV. The guidelines were developed to update the indications for treatment currently considered as effective and to summarize the evidence base for the use of IVIg in dermatological autoimmune diseases and TEN. RESULTS AND CONCLUSION: The current guidelines represent consensual expert opinions and definitions on the use of IVIg reflecting current published evidence and are intended to serve as a decision-making tool for the use of IVIg in dermatological diseases.

Autoantibodies in psoriasis as predictors for loss of response and anti-infliximab antibody induction.

BACKGROUND: Infliximab is successfully used to treat psoriasis and psoriatic arthritis. However, some patients lose therapeutic response after several cycles. Antibodies to infliximab (infliximab-Abs) are induced during treatment in a subgroup of patients and are thought to be associated with loss of response (LOR). Routine screening for infliximab-Abs is expensive and not regularly performed. A reliable and affordable method for identifying patients who are at risk for LOR to infliximab is desirable. OBJECTIVES: To analyse the development of antinuclear antibodies (ANA)/antidouble-stranded DNA antibodies (anti-dsDNA) over time in patients with psoriasis receiving infliximab. To analyse if there is an association between ANA titres/anti-dsDNA concentrations, infliximab-Ab status and LOR. METHODS: A retrospective data analysis of 29 patients with psoriasis receiving infliximab was carried out. ANA titres and anti-dsDNA concentrations were regularly monitored in these patients and sera were tested for infliximab-Abs by enzyme-linked immunosorbent assay. RESULTS: Median ANA titres increased from 1 : 80 [interquartile range (IQR) 0 to 1 : 320, n = 29] pretreatment, to 1 : 1280 (IQR 1 : 640 to 1 : 1920, n = 15) after infusion 10, and 1 : 1920 (IQR 1 : 1280 to 1 : 2560, n = 10) after infusion 20. Infliximab-Abs were found in 21% of patients. Infliximab-Ab-positive patients and patients with LOR had significantly higher pretreatment anti-dsDNA concentrations and higher pretreatment ANA titres than infliximab-Ab-negative and responsive patients, respectively. CONCLUSIONS: The results of this study suggest a role for autoantibodies in the identification of patients with psoriasis at higher risk of developing infliximab-Abs and of LOR under treatment with infliximab.

Induction of interleukin 10-producing, nonproliferating CD4(+) T cells with regulatory properties by repetitive stimulation with allogeneic immature human dendritic cells.

The functional properties of dendritic cells (DCs) are strictly dependent on their maturational state. To analyze the influence of the maturational state of DCs on priming and differentiation of T cells, immature CD83(-) and mature CD83(+) human DCs were used for stimulation of naive, allogeneic CD4(+) T cells. Repetitive stimulation with mature DCs resulted in a strong expansion of alloreactive T cells and the exclusive development of T helper type 1 (Th1) cells. In contrast, after repetitive stimulation with immature DCs the alloreactive T cells showed an irreversibly inhibited proliferation that could not be restored by restimulation with mature DCs or peripheral blood mononuclear cells, or by the addition of interleukin (IL)-2. Only stimulation of T cells with mature DCs resulted in an upregulation of CD154, CD69, and CD70, whereas T cells activated with immature DCs showed an early upregulation of the negative regulator cytotoxic T lymphocyte-associated molecule 4 (CTLA-4). These T cells lost their ability to produce interferon gamma, IL-2, or IL-4 after several stimulations with immature DCs and differentiated into nonproliferating, IL-10-producing T cells. Furthermore, in coculture experiments these T cells inhibited the antigen-driven proliferation of Th1 cells in a contact- and dose-dependent, but antigen-nonspecific manner. These data show that immature and mature DCs induce different types of T cell responses: inflammatory Th1 cells are induced by mature DCs, and IL-10-producing T cell regulatory 1-like cells by immature DCs.

Induction of hapten-specific tolerance by interleukin 10 in vivo.

Interleukin 10 (IL-10) is released during the induction phase of contact sensitivity and was shown in prior functional studies to convert epidermal Langerhans cells (LC) from potent inducers of primary immune responses to specifically tolerizing cells in vitro. To investigate whether IL-10 also subserves the function of a tolerizing agent in vivo ears of BALB/c or C3H mice were injected intradermally with 1-2 micrograms of recombinant mouse (rm)IL-10 8 h before epicutaneous application of 3% trinitrochlorobenzene (TNCB; a contact allergen). As a control, mice were injected with phosphate-buffered saline or IL-10 plus neutralizing amounts of anti-IL-10 mAb. 5 d later, mice were challenged with 1% TNCB on contralateral ears and ear swelling response was measured 24 h later. Whereas control-treated mice showed a normal ear swelling response to epicutaneous challenge (delta mm-2 = 25 +/- 5), ear swelling response of IL-10-treated animals was significantly inhibited (delta mm-2 = 3 +/- 2). Coinjection of IL-10-specific mAb together with rmIL-10 completely abrogated this effect. To differentiate between a state of nonresponsiveness and induction of tolerance by IL-10, mice initially treated with IL-10 and TNCB were resensitized with 3% TNCB in the absence of any treatment after 14 d of rest (group 1). Again mice were challenged 5 d later and ear swelling responses were tested. Whereas control mice treated with allergen alone (group 2) showed a good swelling response (delta mm-2 = 28 +/- 6), IL-10-treated mice (group 1) showed a minimal response towards application of allergen (delta mm-2 = 4 +/- 2). To show that anergy induction by IL-10 was antigen-specific, mice initially treated with IL-10 plus TNCB were exposed to 0.5% dinitrofluorobenzene (DNFB) 14 d later (group 1). After challenge with 0.1% DNFB, IL-10-treated mice showed an ear swelling response (delta mm-2 = 13 +/- 3; group 1) similar to that of control mice only sensitized with DNFB (delta mm-2 = 14 +/- 3; group 3). In an attempt to show the induction of antigen-specific tolerance in these mice in vitro, regional lymph nodes of mice initially treated with TNCB plus IL-10 (group 1) and control-treated mice (groups 2 and 3) were prepared and cultured in the presence of TNBS, dinitrobenzene sulfonate (DNBS), or medium to measure antigen-specific proliferation.(ABSTRACT TRUNCATED AT 400 WORDS)

Identification and functional characterization of human CD4(+)CD25(+) T cells with regulatory properties isolated from peripheral blood.

A subpopulation of peripheral human CD4(+)CD25(+) T cells that expresses CD45RO, histocompatibility leukocyte antigen DR, and intracellular cytotoxic T lymphocyte-associated antigen (CTLA) 4 does not expand after stimulation and markedly suppresses the expansion of conventional T cells in a contact-dependent manner. After activation, CD4(+)CD25(+) T cells express CTLA-4 on the surface detectable for several weeks. These cells show a G1/G0 cell cycle arrest and no production of interleukin (IL)-2, IL-4, or interferon (IFN)-gamma on either protein or mRNA levels. The anergic state of CD4(+)CD25(+) T cells is not reversible by the addition of anti-CD28, anti-CTLA-4, anti-transforming growth factor beta, or anti-IL-10 antibody. However, the refractory state of CD4(+)CD25(+) T cells was partially reversible by the addition of IL-2 or IL-4. These data demonstrate that human blood contains a resident T cell population with potent regulatory properties.

Malignant syphilis with ocular involvement and organism-depleted lesions.

Diagnosis and treatment of syphilis are challenging because of the condition's diverse clinical symptoms, histopathological variance, and the lack of definite tests for treatment follow-up. We report a case of secondary pustular-ulcerative malignant syphilis with ocular involvement in a human immunodeficiency virus-infected patient. It was striking to find that ulcerative lesions can be highly organism depleted.

[Immunology of allergic contact dermatitis]. / Immunologie des allergischen Kontaktekzems.

Eczema is one of the most common skin diseases in dermatological practice. The broad medical definition of eczema includes any acute but non-infectious inflammatory reaction of the skin. The relative homogeneity of both the clinical and histological manifestations of eczema is in stark contrast to the profound pathogenetic differences of its various forms. The group of contact dermatitis can be divided into two main categories: irritant and allergic. Irritant contact dermatitis is due to a principally non- immunological inflammatory reaction of the skin to various physical or chemical irritants. In sharp contrast, allergic contact dermatitis is an antigen-specific cellular immune response of the skin, which in general requires prior antigen-recognition and priming of immune cells. A comprehensive understanding of the complex interactions between immune cells, inflammatory mediators and adhesion molecules in the underlying pathogenesis of allergic contact dermatitis is key for a better functional understanding and the development of new therapeutic strategies.

Identification and induction of human keratinocyte-derived IL-12.

Interleukin 12 is a heterodimeric molecule that serves as a potent co-stimulator enhancing the development of Th1 cells. As one of the classical Th1 cell-mediated responses is contact sensitivity in skin, we wondered whether IL-12 might be produced by epidermal cells and serve as a mediator of this immune response. Using a sensitive, quantitative PCR technique we demonstrate that p35 chain mRNA of IL-12 is produced constitutively by human epidermal cells, whereas p40 chain mRNA can only be detected in epidermis treated with contact allergen, but not epidermis exposed to irritants or tolerogens. Time course studies showed a dramatic induction of IL-12 p40 mRNA 4 h after in vivo allergen treatment reaching peak strength after 6 h. In cell depletion assays we show that epidermal keratinocytes are the major source of this cytokine in the epidermis. This was further supported by analysis of mRNA derived from the human keratinocyte cell line HaCat expressing IL-12 p35 and p40 mRNA upon stimulation. The presence of bioactive IL-12 in supernatants derived from allergen-stimulated epidermal cells was demonstrated by IL-12-specific bioassay. Additional evidence for the functional importance of IL-12 in primary immune reactions in skin was obtained in allogeneic proliferation assays using human haptenated epidermal cells containing Langerhans cells as APC and allogeneic CD4+ T cells as responders. Anti-IL-12 mAb inhibited the proliferation of T cells by approximately 50%. In aggregate our data demonstrate that nonlymphoid keratinocytes are capable of producing functional IL-12 and provide evidence for the functional significance of IL-12 in primary immune responses in skin.

Dendritic cells: key cells for the induction of regulatory T cells?

Even though dendritic cells (DCs) are well known for their capacity to induce immune responses, recent results show that they are also involved in the induction of tolerance. These two contrary effects of otherwise homologous DCs on a developing immune response maybe explainedby different DC developmental stages, i.e., different subsets of DCs may exist and/or different spatial distribution of DCs in the body might influence their function. However, independently from the subtype(s), it is obvious that the ability of DCs to act in a tolerogenic fashion depends on the maturation status, since immature DCs are prone to induce regulatory T cells and hence promote tolerance, whereas mature DCs stimulate effector T cells, facilitating immunity. The means by which DCs convey tolerance are not entirely clear yet, but secretion of suppressive cytokines such as IL-10 and induction of regulatory lymphocytes are involved. In this review we focus on the interaction between DCs and T cells and highlight some mechanisms in the decision-making process of whether immunity or tolerance is induced.