The role of trpa1 in skin physiology and pathology

The transient receptor potential ankyrin 1 (TRPA1), a member of the TRP superfamily of channels, acts as ‘polymodal cellular sensor’ on primary sensory neurons where it mediates the peripheral and central processing of pain, itch, and thermal sensation. However, the TRPA1 expression extends far beyond the sensory nerves. In recent years, much attention has been paid to its expression and function in non-neuronal cell types including skin cells, such as keratinocytes, melanocytes, mast cells, dendritic cells, and endothelial cells. TRPA1 seems critically involved in a series of physiological skin functions, including formation and maintenance of physico-chemical skin barriers, skin cells, and tissue growth and differentiation. TRPA1 appears to be implicated in mechanistic processes in various immunological inflammatory diseases and cancers of the skin, such as atopic and allergic contact dermatitis, psoriasis, bullous pemphigoid, cutaneous T-cell lymphoma, and melanoma. Here, we report recent findings on the implication of TRPA1 in skin physiology and pathophysiology. The potential use of TRPA1 antagonists in the treatment of inflammatory and immunological skin disorders will be also addressed

Immune-Mediated Dermatoses in Patients with Haematological Malignancies: A Comprehensive Review

Haematological malignancies induce important alterations of the immune system, which account for the high frequency of autoimmune complications observed in patients. Cutaneous immune-mediated diseases associated with haematological malignancies encompass a heterogeneous group of dermatoses, including, among others, neutrophilic and eosinophilic dermatoses, autoantibody-mediated skin diseases, vasculitis and granulomatous dermatoses. Some of these diseases, such as paraneoplastic pemphigus, are associated with an increased risk of death; others, such as eosinophilic dermatoses of haematological malignancies, run a benign clinical course but portend a significant negative impairment on a patient's quality of life. In rare cases, the skin eruption reflects immunological alterations associated with an unfavourable prognosis of the associated haematological disorder. Therapeutic management of immune-mediated skin diseases in patients with haematological malignancies is often challenging. Systemic corticosteroids and immunosuppressive drugs are considered frontline therapies but may considerably augment the risk of serious infections. Indeed, developing a specific targeted therapeutic approach is of crucial importance for this particularly fragile patient population. This review provides an up-to-date overview on the immune-mediated skin diseases most frequently encountered by patients with onco-haematological disorders, discussing new pathogenic advances and therapeutic options on the horizon

Profile of a Cohort of 78 Italian Patients with Mucous Membrane Pemphigoid: Correlation Between Reactivity Profile and Clinical Involvement

Direct diagnosis of mucous membrane pemphigoid (MMP) is not easy. Circulating autoantibodies targeting bullous pemphigoid antigens of 180 kDa and 230 kDa (BP180 and BP230), \u3b16\u3b24 integrin, laminin 332 and type VII collagen (Col VII) are not always present. The aims of this study were to characterize the humoral immune response of a cohort of Italian patients with MMP, its association with clinical involvement and severity, and to design an algorithm for efficient serological diagnosis. Seventy-eight MMP sera were studied retrospectively by indirect immunofluorescence on salt-split skin, enzyme-linked immunosorbent assay (ELISA) and immunoblotting. Indirect immunofluorescence on salt-split skin resulted in the most sensitive approach for diagnosis of MMP. BP180 was the major autoantigen in MMP patients with oral and cutaneous involvement. Significant associations were found between BP180 reactivity and oral and cutaneous localization of the lesions (p\u2009=\u20090.006), and between Col VII positivity and Setterfield severity score (p\u2009=\u20090.020)

Rationale and design of the RESOLVE trial: lanreotide as a volume reducing treatment for polycystic livers in patients with autosomal dominant polycystic kidney disease

Contains fulltext : 109282.pdf (publisher's version ) (Open Access)BACKGROUND: A large proportion of patients with autosomal dominant polycystic kidney disease (ADPKD) suffers from polycystic liver disease. Symptoms arise when liver volume increases. The somatostatin analogue lanreotide has proven to reduce liver volume in patients with polycystic liver disease. However, this study also included patients with isolated polycystic liver disease (PCLD). The RESOLVE trial aims to assess the efficacy of lanreotide treatment in ADPKD patients with symptomatic polycystic livers. In this study we present the design of the RESOLVE trial. METHODS/DESIGN: This open-label clinical trial evaluates the effect of 6 months of lanreotide in ADPKD patients with symptomatic polycystic livers. Primary outcome is change in liver volume determined by computerised tomography-volumetry. Secondary outcomes are changes in total kidney volume, kidney intermediate volume and renal function. Furthermore, urinary (NGAL, alpha1-microglobulin, KIM-1, H-FABP, MCP-1) and serum (fibroblast growth factor 23) biomarkers associated with ADPKD disease severity are assessed to investigate whether these biomarkers predict treatment responses to lanreotide. Moreover, safety and tolerability of the drug in ADPKD patients will be assessed. DISCUSSION: We anticipate that lanreotide is an effective therapeutic option for ADPKD patients with symptomatic polycystic livers and that this trial aids in the identification of patient related factors that predict treatment response. TRIAL REGISTRATION NUMBER: Clinical trials.gov NCT01354405

Global Activation of CD8+ Cytotoxic T Lymphocytes Correlates with an Impairment in Regulatory T Cells in Patients with Generalized Vitiligo

Melanocyte-specific CD8+ cytotoxic T lymphocytes (CTLs) play a pivotal role in vitiligo-induced depigmentation. Yet, the mechanisms underlying the high frequency of generalized autoimmune disorders associated with generalized vitiligo (GV) are unknown. We hypothesized that an imbalance between activated CD8+ CTLs and regulatory T cells (Tregs) exists in patients with GV . Assessment of the circulating CD8+ CTLs and Tregs by flow cytometric analysis revealed an obvious expansion of CD8+ CTLs and a concomitant decrease in Treg cells in GV patients. The percentages of skin infiltrating CD8+ CTLs and Tregs were evaluated by immunohistochemistry and revealed dramatically increased numbers of both CD8+ CTLs and Tregs in the perilesional skin of GV patients. However, peripheral Tregs were impaired in their ability to suppress the proliferation and cytolytic capacity of autologous CD8+ T cells, suggesting that a functional failure of Tregs and the hyper-activation of CD8+ CTLs may contribute to progressive GV. Our data indicate that reduced numbers and impaired function of natural Tregs fail to control the widespread activation of CD8+ CTLs, which leads to the destruction of melanocytes and contributes to the elevated frequency of various associated autoimmune diseases. This knowledge furthers our understanding of the mechanisms of immune tolerance that are impaired in GV patients and may aid in the future development of effective immunotherapy for GV patients

Updated S2 K guidelines for the management of bullous pemphigoid initiated by the European Academy of Dermatology and Venereology (EADV).

BACKGROUND Bullous pemphigoid (BP) is the most common autoimmune subepidermal blistering disease of the skin and mucous membranes. This disease typically affects the elderly and presents with itch and localized or, most frequently, generalized bullous lesions. A subset of patients only develops excoriations, prurigo-like lesions, and eczematous and/or urticarial erythematous lesions. The disease, which is significantly associated with neurological disorders, has high morbidity and severely impacts the quality of life. OBJECTIVES AND METHODOLOGY The Autoimmune blistering diseases Task Force of the European Academy of Dermatology and Venereology sought to update the guidelines for the management of BP based on new clinical information, and new evidence on diagnostic tools and interventions. The recommendations are either evidence-based or rely on expert opinion. The degree of consent among all task force members was included. RESULTS Treatment depends on the severity of BP and patients' comorbidities. High-potency topical corticosteroids are recommended as the mainstay of treatment whenever possible. Oral prednisone at a dose of 0.5 mg/kg/day is a recommended alternative. In case of contraindications or resistance to corticosteroids, immunosuppressive therapies, such as methotrexate, azathioprine, mycophenolate mofetil or mycophenolate acid, may be recommended. The use of doxycycline and dapsone is controversial. They may be recommended, in particular, in patients with contraindications to oral corticosteroids. B-cell-depleting therapy and intravenous immunoglobulins may be considered in treatment-resistant cases. Omalizumab and dupilumab have recently shown promising results. The final version of the guideline was consented to by several patient organizations. CONCLUSIONS The guidelines for the management of BP were updated. They summarize evidence- and expert-based recommendations useful in clinical practice

Fluorescent Microangiography Is a Novel and Widely Applicable Technique for Delineating the Renal Microvasculature

Rarefaction of the renal microvasculature correlates with declining kidney function. However, current technologies commonly used for its evaluation are limited by their reliance on endothelial cell antigen expression and assessment in two dimensions. We set out to establish a widely applicable and unbiased optical sectioning method to enable three dimensional imaging and reconstruction of the renal microvessels based on their luminal filling. The kidneys of subtotally nephrectomized (SNx) rats and their sham-operated counterparts were subjected to either routine two-dimensional immunohistochemistry or the novel technique of fluorescent microangiography (FMA). The latter was achieved by perfusion of the kidney with an agarose suspension of fluorescent polystyrene microspheres followed by optical sectioning of 200 µm thick cross-sections using a confocal microscope. The fluorescent microangiography method enabled the three-dimensional reconstruction of virtual microvascular casts and confirmed a reduction in both glomerular and peritubular capillary density in the kidneys of SNx rats, despite an overall increase in glomerular volume. FMA is an uncomplicated technique for evaluating the renal microvasculature that circumvents many of the limitations imposed by conventional analysis of two-dimensional tissue sections