Quantitative analysis of the natural history of prolidase deficiency: description of 17 families and systematic review of published cases.

PURPOSE: Prolidase deficiency is a rare inborn error of metabolism causing ulcers and other skin disorders, splenomegaly, developmental delay, and recurrent infections. Most of the literature is constituted of isolated case reports. We aim to provide a quantitative description of the natural history of the condition by describing 19 affected individuals and reviewing the literature. METHODS: Nineteen patients were phenotyped per local institutional procedures. A systematic review following PRISMA criteria identified 132 articles describing 161 patients. Main outcome analyses were performed for manifestation frequency, diagnostic delay, overall survival, symptom-free survival, and ulcer-free survival. RESULTS: Our cohort presented a wide variability of severity. Autoimmune disorders were found in 6/19, including Crohn disease, systemic lupus erythematosus, and arthritis. Another immune finding was hemophagocytic lymphohistiocytosis (HLH). Half of published patients were symptomatic by age 4 and had a delayed diagnosis (mean delay 11.6 years). Ulcers were present initially in only 30% of cases, with a median age of onset at 12 years old. CONCLUSION: Prolidase deficiency has a broad range of manifestations. Symptoms at onset may be nonspecific, likely contributing to the diagnostic delay. Testing for this disorder should be considered in any child with unexplained autoimmunity, lower extremity ulcers, splenomegaly, or HLH.

Activated melanoma vessels: A sticky point for successful immunotherapy.

Metastatic melanoma is a devastating disease with a marginal-albeit increasing-hope for cure. Melanoma has a high mutation rate which correlates to the expression of numerous neo-antigens and thus is associated with the potential to induce and strengthen effective antitumoral immunity. However, the incomplete and potentially insufficient response to established immunotherapies (response rates usually do not markedly exceed 60%) already points to the need of further studies to improve treatment strategies. Multiple tumor escape mechanisms that allow melanoma to evade from antitumoral immune responses have been characterized and must be overcome to achieve a better clinical efficacy of immunotherapies. Recently, promising progress has been made in targeting tumor vasculature to control and increase the infiltration of tumors with effector lymphocytes. It has been hypothesized that amplified lymphocytic infiltrates in melanoma metastases result in a switch of the tumor microenvironment from a non-inflammatory to an inflammatory state. In this view point essay, we discuss the requirements for successful homing of lymphocytes to melanoma tissue and we present a mouse melanoma xenograft model that allows the investigation of human tumor vessels in vivo. Furthermore, current clinical studies dealing with the activation of melanoma vasculature for enhanced effectiveness of immunotherapy protocols are presented and open questions for routine clinical application are addressed.

Activation of human vascular endothelium in melanoma metastases induces ICAM-1 and E-selectin expression and results in increased infiltration with effector lymphocytes.

Lymphocytic infiltration into melanoma tissue is an important prerequisite for effective antitumoral immunity. However, analysis of human metastatic melanoma has shown that leucocyte adhesion receptor expression on melanoma blood vessels is very low or absent, thereby impairing the entry of cytotoxic lymphocytes into tumor tissue. We hypothesized that adhesion molecules can be induced on melanoma vasculature allowing better infiltration of cytotoxic lymphocytes. Quantitative real-time PCR and immunofluorescence staining indicated that the adhesion molecules ICAM-1 (CD54) and E-selectin (CD62E) can be significantly induced by intralesional application of TNF alpha in tissue from human melanoma metastases either in vitro or in vivo when grafted onto immunodeficient NSG (NOD.Cg-PrkdcscidIl2rgtm1Wjl/SzJ) mice that preserved human vessels. Furthermore, activated human autologous CD3+ lymphocytes were injected intravenously into mice bearing melanoma xenografts treated with TNF-α or PBS in addition to the leucocyte chemoattractant TARC (CCL17). Significantly increased numbers of CD8+ cells were detected in TNF-α-treated melanoma metastases compared with PBS-treated controls. In addition, tumor cell apoptosis was enhanced and melanoma cell proliferation reduced as shown by TUNEL assay and KI-67 staining. We conclude that adhesion molecules can be induced on human melanoma vasculature resulting in significantly improved homing of activated autologous cytotoxic T cells to melanoma tissue and inhibition of melanoma cell proliferation. These observations should be considered when designing protocols for immunotherapy of malignant melanoma.

Systemic therapies for leg ulcers.

Successful management of patients with leg ulcers requires identification of the underlying etiology, with subsequent initiation of causal treatment, if feasible. Supplementary measures of first choice include stage-adjusted wound treatment, usually combined with compression therapy. The significance of systemic drugs has been the subject of controversial debate, depending on the underlying cause of the condition. The present review article is therefore meant to highlight current aspects of systemic drug therapies for the treatment of leg ulcers associated with chronic venous insufficiency, peripheral arterial disease, livedoid vasculopathy, vasculitis, necrobiosis lipoidica, calciphylaxis and pyoderma gangrenosum. In summary, the majority of therapeutic options presented herein are used off-label. While systemic drugs are promising options for the more common types of wounds such as venous, mixed or arterial leg ulcers, they do not represent the current standard of treatment. By contrast, systemic agents play a key role in the management of many of the other disorders presented herein. These agents primarily include immunomodulatory and rheological drugs used to expedite wound healing.

Single platelets seal neutrophil-induced vascular breaches via GPVI during immune-complex-mediated inflammation in mice.

Platelets protect vascular integrity during inflammation. Recent evidence suggests that this action is independent of thrombus formation and requires the engagement of glycoprotein VI (GPVI), but it remains unclear how platelets prevent inflammatory bleeding. We investigated whether platelets and GPVI act primarily by preventing detrimental effects of neutrophils using models of immune complex (IC)-mediated inflammation in mice immunodepleted in platelets and/or neutrophils or deficient in GPVI. Depletion of neutrophils prevented bleeding in thrombocytopenic and GPVI(-/-) mice during IC-mediated dermatitis. GPVI deficiency did not modify neutrophil recruitment, which was reduced by thrombocytopenia. Neutrophil cytotoxic activities were reduced in thrombocytopenic and GPVI(-/-) mice during IC-mediated inflammation. Intravital microscopy revealed that in this setting, intravascular binding sites for platelets were exposed by neutrophils, and GPVI supported the recruitment of individual platelets to these spots. Furthermore, the platelet secretory response accompanying IC-mediated inflammation was partly mediated by GPVI, and blocking of GPVI signaling impaired the vasculoprotective action of platelets. Together, our results show that GPVI plays a dual role in inflammation by enhancing neutrophil-damaging activities while supporting the activation and hemostatic adhesion of single platelets to neutrophil-induced vascular breaches.

von Willebrand factor fibers promote cancer-associated platelet aggregation in malignant melanoma of mice and humans.

Tumor-mediated procoagulatory activity leads to venous thromboembolism and supports metastasis in cancer patients. A prerequisite for metastasis formation is the interaction of cancer cells with endothelial cells (ECs) followed by their extravasation. Although it is known that activation of ECs and the release of the procoagulatory protein von Willebrand factor (VWF) is essential for malignancy, the underlying mechanisms remain poorly understood. We hypothesized that VWF fibers in tumor vessels promote tumor-associated thromboembolism and metastasis. Using in vitro settings, mouse models, and human tumor samples, we showed that melanoma cells activate ECs followed by the luminal release of VWF fibers and platelet aggregation in tumor microvessels. Analysis of human blood samples and tumor tissue revealed that a promoted VWF release combined with a local inhibition of proteolytic activity and protein expression of ADAMTS13 (a disintegrin-like and metalloproteinase with thrombospondin type I repeats 13) accounts for this procoagulatory milieu. Blocking endothelial cell activation by the low-molecular-weight heparin tinzaparin was accompanied by a lack of VWF networks and inhibited tumor progression in a transgenic mouse model. Our findings implicate a mechanism wherein tumor-derived vascular endothelial growth factor-A (VEGF-A) promotes tumor progression and angiogenesis. Thus, targeting EC activation envisions new therapeutic strategies attenuating tumor-related angiogenesis and coagulation.

Chronic venous insufficiency - a review of pathophysiology, diagnosis, and treatment.

Chronic venous disease is a common disorder associated with a variety of symptoms in later disease stages but also with complications such as venous leg ulcer. This, in turn, has substantial socioeconomic effects and significantly impacts patients' quality of life. While there are a number of diagnostic procedures available, color-flow duplex ultrasound has become the gold standard. As regards therapeutic options, major advances have been made in recent decades. Today, there are alternatives to saphenofemoral ligation and stripping of the great saphenous vein, including endovenous thermal ablation techniques. However, treatment selection continues to depend on many factors such as individual anatomical circumstances and disease stage. The following article provides an overview of the anatomy and pathophysiology as well as current diagnostic and therapeutic standards.

Die chronische venöse Insuffizienz - Eine Zusammenfassung der Pathophysiologie, Diagnostik und Therapie.

Die chronische Venenerkrankung ist eine weit verbreitete Krankheit, die in späteren Stadien mit einer Vielzahl an Symptomen, aber auch Komplikationen wie dem Ulcus cruris, einhergeht. Dies wiederum hat weitreichende Auswirkungen auf die Lebensqualität der Patienten wie auch auf das Gesundheitssystem. Für die Diagnostik der chronischen Venenerkrankungen steht eine Auswahl an Verfahren zur Verfügung, wobei sich die farbkodierte Duplexsonographie als Goldstandard etabliert hat. Im Bereich der Therapie kam es in den letzten Jahrzehnten zu großen Fortschritten, sodass heute auch Alternativen zum klassischen Stripping durch die endoluminalen Verfahren zur Verfügung stehen. Die Wahl der Therapieoption ist jedoch weiterhin stark abhängig von mehreren Faktoren, unter anderem von den anatomischen Gegebenheiten und dem Krankheitsstadium. Im folgenden Artikel werden die Anatomie und Pathophysiologie, sowie die aktuellen Standards der Diagnostik und Therapie zusammengefasst.

Sclerotherapy of varicose veins in dermatology.

Venous disorders rank among the most frequent diseases in the German population. Early diagnostic investigation and treatment can prevent their progression and may reduce the risk for secondary diseases. The therapeutic spectrum for varicose veins includes conservative as well as interventional and surgical methods. Because it is minimally invasive and well-tolerated, sclerotherapy represents an important treatment method for venous insufficiency, recurrent varicosis and venous malformations. We review the role of sclerotherapy as a treatment option of chronic venous insufficiency in dermatology.

Modern wound care - practical aspects of non-interventional topical treatment of patients with chronic wounds.

The treatment of patients with chronic wounds is becoming increasingly complex. It was therefore the aim of the members of the working group for wound healing (AGW) of the German Society of Dermatology (DDG) to report on the currently relevant aspects of non-interventional, topical wound treatment for daily practice. -Beside necessary procedures, such as wound cleansing and débridement, we describe commonly used wound dressings, their indications and practical use. Modern antiseptics, which are currently used in wound therapy, usually contain polyhexanide or octenidine. Physical methods, such as negative-pressure treatment, are also interesting options. It is always important to objectify and adequately treat pain symptoms which often affect these patients. Modern moist wound therapy may promote healing, reduce complications, and improve the quality of life in patients with chronic wounds. Together with the improvement of the underlying causes, modern wound therapy is an important aspect in the overall treatment regime for patients with chronic wounds.

Early treatment with rutoside and ascorbic acid is highly effective for progressive pigmented purpuric dermatosis.

BACKGROUND AND OBJECTIVES: Progressive pigmented purpuric dermatosis (PPPD, Schamberg disease) is a rare benign, but chronic dermatosis frequently misdiagnosed as vasculitis or bleeding disorder. Although affected patients experience significant impairment in quality of life no effective treatment has been established. The aim of our two center case series was to evaluate efficacy and tolerability of the antioxidants rutoside and ascorbic acid as combination treatment for PPPD. PATIENTS AND METHODS: A retrospective review was performed on 35 patients with PPPD treated with 2 × 50 mg rutoside and 1,000 mg ascorbic acid daily between 2004 until 2011. The mean treatment duration was 8.2 months. RESULTS: 71.4% of the participants experienced complete clearance and 20.0% an improvement of more than 50%, accompanied by increased quality of life. Nine participants (25.1%) relapsed after discontinuation. In seven, rutoside and ascorbic acid was re-initiated, and all responded again. Only three participants reported mild adverse effects. Participants with shorter disease duration showed better therapeutic success, shorter time to response and lower risk of recurrence. CONCLUSION: Oral rutoside and ascorbic acid may be an efficient and well tolerated treatment for PPPD. Early treatment is recommended to achieve best clinical outcome.

Development of a cellular assay as a personalized model for testing chronic wound therapeutics.

Exudates of non-healing wounds contain drivers of pathogenicity. We utilized >800 exudates from non-healing and healing wounds of diverse etiologies, collected by three different methods, to develop a wound-specific, cell-based functional biomarker assay. Human dermal fibroblast proliferation served as readout to a) to differentiate between healing and non-healing wounds, b) follow the healing process of individual patients, and c) assess the effects of therapeutics for chronic wounds ex vivo. We observed a strong correlation between wound chronicity and inhibitory effects of individual exudates on fibroblast proliferation, with good diagnostic sensitivity (76-90%, depending on the sample collection method). Transition of a clinically non-healing to a healing phenotype restored fibroblast proliferation and extracellular matrix formation while reducing inflammatory cytokine production. Transcriptional analysis of fibroblasts exposed to ex vivo non-healing wound exudates revealed an induction of inflammatory cytokine- and chemokine pathways and the unfolded protein response, indicating that these changes may contribute to the pathology of non-healing wounds. Testing the wound therapeutics platelet derived growth factor and silver sulfadiazine yielded responses in line with clinical experience and indicate the usefulness of the assay to search for and profile new therapeutics.

Is MC1 dispensable for regulation of cutaneous inflammatory and immune responses?

The melanocortin-1 receptor (MC1 ) - being most abundantly expressed in the skin by melanocytes - has a physiological role for melanin pigmentation in many vertebrate species. MC1 has also been implicated in regulation of skin inflammation as this receptor is detectable in the majority of non-melanocytic cell types and its ligand α-melanocyte-stimulating hormone (α-MSH) exerts immunoregulatory and anti-inflammatory effects. However, in vivo studies on mice with targeted disruption of MC1 have been missing in the context of skin inflammation until recently. Wolnicka-Glubisz et al. now reported that the course of ultraviolet (UV)-induced inflammation, contact hypersensitivity, neonatal immune tolerance and UV-induced immunosuppression is similar in MC1 signal-deficient (C57BL/6-Mc1r(e/e)) and wild-type mice. These unexpected findings are supported by own observations in experimentally induced immune-complex-mediated vasculitis: Mc1r(e/e) mice exhibited a similar extent of the reverse passive cutaneous Arthus reaction compared with wild-type animals. Future studies are thus needed to clarify whether these findings are due to limitations in the chosen mouse model and/or point to additional MC subtypes that may regulate inflammatory and immune responses in the skin.

Molecular imaging reveals time course of matrix metalloproteinase activity in acute cutaneous vasculitis in vivo.

Matrix metalloproteinases (MMPs) play a critical role in various pathological conditions including cutaneous inflammation. Thus far, serial assessment of MMP activity in ongoing inflammation is hampered due to technical limitations. Here, we present an innovative method for longitudinal detection of MMP activity by in vivo imaging. First, we analysed skin sections from patients suffering from leucocytoclastic vasculitis (LcV) and detected a significant MMP signal via immunofluorescence staining. Then, we mimicked LcV in mice in a well-studied model of immune complex-mediated vasculitis (ICV). This acute inflammatory process was serially visualized in vivo using the fluorescence-labelled MMP tracer Cy5.5-AF443. The deposition of fluorescence-labelled immune complexes and MMP tracer distribution was visualized repeatedly and non-invasively by fluorescence reflectance imaging. In correlation with the presence of MMP-2 and MMP-9 in immunofluorescence stainings, Cy5.5-AF443 accumulated in ICV spots in the skin of C57BL/6 mice. This tracer accumulation could also be observed in mice equipped with a dorsal skinfold chamber, where microscopic observations revealed an increased recruitment of fluorescence-labelled leucocytes during ICV. The specificity of the MMP tracer was supported by (i) analysis of mice deficient in functional ß2 -integrins (CD18(-/-) ) and (ii) subsequent MMP immunofluorescence staining. These findings let us conclude that MMP accumulation in the acute phase of ICV depends on ß2 -mediated leucocyte recruitment. In summary, we show that MMPs are involved in ICV as determined by Cy5.5-AF443, a new optical marker to longitudinally and non-invasively follow MMP activity in acute skin inflammation in vivo.

Livedoid vasculopathy - a thrombotic disease.

Livedoid vasculopathy is a rare, chronic occlusive disease of vessels supporting the upper layers of the skin. It is characterized by purpuric maculae and recurrent painful ulcerations mostly affecting the lower leg. These ulcerations occur episodically especially in summer time and heal slowly, leaving characteristic porcelain-white scars called ’atrophie blanche’.This review is focused on the current knowledge on livedoid vasculopathy and modern therapy strategies resulting from its etiopathogenetic associations with prothrombotic states. Livedoid vasculopathy and its pathophysiology are clearly distinguished from inflammatory vasculitis and thus require a different therapeutic approach. The prevention of irreversible residual scarring and improving the quality of life of patients in this often misdiagnosed disease is one of the main treatment goals.