Journal of Investigative Dermatology RSS feed.
Updated: 1 hour 25 min ago
The loss of primary cilia on melanocytes is a useful biomarker for the distinction of melanoma from conventional melanocytic nevi. It is unknown whether ciliation status is beneficial for diagnosing spitzoid tumors - a subclass of melanomas that present inherently ambiguous histology and are challenging to classify. We evaluated ciliation index (CI) in 68 cases of spitzoid tumors ranging from Spitz nevi (SN) and atypical Spitz tumors (AST) to spitzoid melanoma (SM). We found a significant decrease in CI within the SM group when compared to either the SN or AST groups.
RNase 7 is one of the major antimicrobial peptides (AMPs) secreted by keratinocytes. The AMPs hBD-2 and LL-37 promote TLR9-mediated activation of human plasmacytoid dendritic cells (pDCs) by human self-DNA; however, whether keratinocytes respond in a similar way has not yet been addressed. Keratinocytes express several receptors for the detection of cytosolic DNA. Here, we investigated the activation of keratinocytes by RNase 7 in combination with human DNA. Stimulation of keratinocytes with RNase 7 and human DNA induced a strong increase of IP-10 production.
To the Editor, The regular use of sunscreen products protects against sunburn, photo-aging and skin cancer (Waldman and Grant-Kels, 2019). A recent Australasian Sunscreen Summit recommended that sunscreens should be applied daily when the UV index is expected to be 3 or more to decrease future skin cancer incidence (Whiteman et al., 2019). However, although Australia has one of the highest rates of skin cancer in the world, only 55 percent of Australians believed it was safe to use sunscreen every day (Cancer Council Australia, 2017).
Melanoma is cancer caused by the neoplastic transformation of melanocytes. The last decade has witnessed a surge in treatment options for advanced melanoma patients, especially immunotherapeutic interventions; nonetheless, issues such as drug resistance, limited efficacy, and high-toxicity ensue (Luke et al., 2017). Understanding the mechanisms underpinning melanoma progression and invasion is, therefore, vital for the development of treatment strategies.
NIPP1 is a ubiquitously expressed nuclear protein that regulates functions of protein Ser/Thr phosphatase-1 in cell proliferation and lineage specification. The role of NIPP1 in tissue homeostasis is not fully understood. Here we show that the selective deletion of NIPP1 in mouse epidermis resulted in epidermal hyperproliferation, a reduced adherence of basal keratinocytes and a gradual decrease in the stemness of hair follicle stem cells, culminating in hair loss. This complex phenotype was associated with chronic sterile skin inflammation and could be partially rescued by dexamethasone treatment.
The interleukin (IL)-23/T-helper type 17 cell axis is a target for psoriasis. The tyrosine kinase 2 (TYK2)/Janus kinase 1 (JAK1) inhibitor, PF-06700841, will directly suppress TYK2-dependent IL-12 and IL-23 signaling and JAK1-dependent signaling in cells expressing these signaling molecules, including T cells and keratinocytes. This clinical study sought to define the inflammatory gene and cellular pathways through which PF-06700841 improves the clinical manifestations of psoriasis. Patients (n=30) with moderate-to-severe psoriasis were randomized to once-daily 30 mg (n=14) or 100 mg (n=7) PF-06700841, or placebo (n=9) for 28 days.
Streptococcus pyogenes tonsillar infection is well-known to trigger and exacerbate psoriasis lesions in both guttate and plaque forms of the disease. Although mucosal and cutaneous tissues are closely involved in psoriasis pathology, the interaction between their specific immune responses has not been deeply explored. This work aims to address and characterize the presence of humoral responses against Streptococcus pyogenes in psoriasis patients and its putative association with cytokine responses detected in vitro in our psoriasis ex vivo model, based on the coculture of CLA+/- T cells with autologous epidermal cells.
In an era of increased complexity of clinical research, a demand for personalized medicine, an increasing value of diversity, a focus on digital health, and a call for patient-centricity, the discovery and development of new medicines, more than ever, is dependent on collaboration between multiple stakeholders (Figure 1).
Oncogenic mutations in the Braf-kinase gene represent the most frequent genomic driver in acquired melanocytic nevi and in cutaneous melanomas. It is currently thought that oncogene-induced senescence and cell cycle arrest limit the ability of oncogenic Braf to promote melanocyte proliferation in benign nevi. The molecular and cellular mechanisms that allow an oncogenic Braf mutation to fully transform melanocytes into invasively growing melanoma cells that are able to metastasize systemically are only partially understood.
Our group has recently shown that keratinocyte-derived IL-17E (IL-25), one of six members of the IL-17 family, is overexpressed in lesional psoriatic skin and is involved in its pathophysiology. We show here that IL-22 enhances IL-17E production in human keratinocytes and that these cells display a complete IL-17E receptor at their surface, which expression is further induced by IL-17A, indicating a potential autocrine effect of IL-17E. Therefore, we addressed the impact of IL-17E on the function of human primary keratinocytes.
We recently demonstrated that a synthetic silent information regulator T1 (SIRT1) activator, Hexacarboxymethyldipeptide-12 (HMD-12), protects the skin against damages caused by ultraviolet irradiation (Lim et al., 2017). In addition, in one study, SIRT1 activation has been shown to promote keratinocyte (KC) differentiation, which is a critical process for the formation of the epidermal barrier, but the cellular mechanism underlying the SIRT1-mediated KC differentiation has remained unknown (Blander et al., 2009).
To the Editor, Morphea is an autoimmune disease that causes fibrosis of the skin that may result in significant morbidity. Eosinophilic fasciitis (EF) may be considered a deeper form of morphea, and features of both morphea and EF can be present in individual patients. Morphea and EF have been postulated to have pathogenic features that overlap with systemic sclerosis (Laxer and Zulian, 2006). In these diseases, dysregulated immune responses are thought to induce fibrosis (Torok et al., 2019). Treatment of these diseases with non-specific immunosuppressants such as corticosteroids is often ineffective and associated with toxicity.
Systemic sclerosis (SSc) is a rare and severe connective tissue disease combining auto-immune and vasculopathy features, ultimately leading to organ fibrosis. Impaired angiogenesis is an often silent and life-threatening complication of the disease. We hypothesize that CCN3 (NOV), a member of the CCN family of extra-cellular matrix proteins, which is an antagonist of the pro-fibrotic protein CCN2 (CTGF) as well as a pro-angiogenic factor, is implicated in SSc pathophysiology.We performed skin biopsies on 26 SSc patients, both in fibrotic and non-fibrotic areas for 17 patients, and collected 18 healthy control skin specimens, for immunohistochemistry and cell culture.
Ultraviolet (UV)-induced DNA damage, suppression of anti-tumor immune responses and promotion of cutaneous inflammation underly the skin tumor promoting activities of sunlight. Targeting the immune regulatory pathways activated by UV is proving a highly effective therapeutic strategy to treat both melanoma (Hodi et al., 2010) and keratinocyte cancers (Day et al., 2017). However, many of these first generation check-point inhibitors come with significant side effects including increased risk of autoimmune toxicities (Phan et al., 2003) and rejection of allografts in some transplant recipients at high risk of metastatic skin cancer (Abdel-Wahab et al., 2019).
Dermatomyositis (DM) is a chronic inflammatory and autoimmune disorder belonging to the idiopathic inflammatory myopathies affecting primarily skin and muscle with variable extent. Disease mechanism comprehension is growing, with a pivotal role of both the innate and adaptive immune system and involvement of both cellular and humoral actors (Nagaraju and Lundberg, 2011). The immune transcriptomic signature of DM is characterized by a type I IFN signature in peripheral blood mononuclear cells, muscle, and skin, which has been shown to correlate with disease activity (Baechler et al., 2011; Walsh et al., 2007; Wong et al., 2012); consequently, targeting type I IFN seems to represent a novel therapeutic approach in DM (Higgs et al., 2014).
Patient-Reported Outcome Measures (PROMs) have been used in research for decades. Increasingly PROMs are being used in clinical practice to systematically address, and monitor over time, how patients feel and function in daily life. Using PROMs empowers patients to discuss health issues, which improves communication and contributes to informed decision making, in line with the principles of delivering value-based health care (Rotenstein et al., 2017).
We are witnessing the broad implementation of new treatments for psoriasis, resulting from the research on genetics and pathogenesis and from the development of new targeted treatments.
Generalized pustular psoriasis (GPP) represents a rare pustular disease manifesting as a multi-systemic inflammation in a chronic or episodic course, sometimes as life-threatening incidents. Bi-allelic IL36RN mutations are known to be disease-causing/ -contributing in 21-41% of GPP patients (Hussain et al., 2015, Marrakchi et al., 2011, Mossner et al., 2018, Onoufriadis et al., 2011, Sugiura et al., 2013). IL-36 binds to the IL-36-receptor(IL-36R)-complex, thereby triggering the activation of MAPK and NF-κB, resulting in production of pro-inflammatory cytokines.
Neutrophils are broadly classified into conventional neutrophils (PMNs) and low density granulocytes (LDGs). LDGs are better than PMNs in the generation of NETs, which may contribute to the pathology of autoimmune diseases. We hypothesized that LDGs and PMNs differ in levels of unrestrained neutrophil elastase (NE) that supports NET generation. Here, we show that individuals with psoriasis contain elevated levels of LDGs and that in contrast to PMNs, LDGs display higher staining for NE and lower staining for its inhibitor SLPI.