Anti-NC16A IgA from Patients with Linear IgA Bullous Dermatosis Induce Neutrophil-Dependent Subepidermal Blistering in Mice

Linear IgA bullous dermatosis (LABD) is an acquired autoimmune subepidermal blistering skin disease characterized by circulating and tissue-bound IgA autoantibodies that recognize epitopes within the hemidesmosomal protein BP180, including its NC16A domain. Histologically, LABD has long been defined by neutrophil infiltration and dermal-epidermal separation. However, the pathogenic roles of anti-NC16A IgA and neutrophils in LABD, as well as their interactions, have not been thoroughly studied. We show that passive transfer of patient-derived anti-NC16A IgA induce clinical and histologic LABD pathology in humanized NC16A mice that are reconstituted locally or systemically with human neutrophils. The lesional skin of mice exhibits significantly elevated levels of the neutrophil chemoattractants CXCL-1 and CXCL-2. Furthermore, we show significantly increased levels of the neutrophil chemoattractant IL-8 in blister fluids of patients with LABD. This study provides direct evidence that anti-NC16A IgA in patients with LABD are pathogenic and interact with neutrophils to mediate tissue injury and subepidermal blister formation. This study further corroborates the importance of neutrophil-mediated tissue injury in LABD disease physiology and establishes a clinically relevant in vivo model system that can be used to systematically dissect the immunopathogenesis of LABD.

The Eotaxin-1/CCR3 Axis and Matrix Metalloproteinase-9 Are Critical in Anti-NC16A IgE-Induced Bullous Pemphigoid

Bullous pemphigoid (BP) is the most common autoimmune bullous skin disease of humans and is characterized by eosinophilic inflammation and circulating and tissue-bound IgG and IgE autoantibodies directed against two hemidesmosomal proteins: BP180 and BP230. The noncollagenous 16A domain (NC16A) of BP180 has been found to contain major epitopes recognized by autoantibodies in BP. We recently established the pathogenicity of anti-NC16A IgE through passive transfer of patient-derived autoantibodies to double-humanized mice that express the human high-affinity IgE receptor, FcεRI, and human NC16A domain (FcεRI/NC16A). In this model, anti-NC16A IgEs recruit eosinophils to mediate tissue injury and clinical disease in FcεRI/NC16A mice. The objective of this study was to characterize the molecular and cellular events that underlie eosinophil recruitment and eosinophil-dependent tissue injury in anti-NC16A IgE-induced BP. We show that anti-NC16A IgEs significantly increase levels of key eosinophil chemoattractants, eotaxin-1 and eotaxin-2, as well as the proteolytic enzyme matrix metalloproteinase-9 (MMP-9) in the lesional skin of FcεRI/NC16A mice. Importantly, neutralization of eotaxin-1, but not eotaxin-2, and blockade of the main eotaxin receptor, CCR3, drastically reduce anti-NC16A IgE-induced disease activity. We further show that anti-NC16A IgE/NC16A immune complexes induce the release of MMP-9 from eosinophils, and that MMP-9-deficient mice are resistant to anti-NC16A IgE-induced BP. Lastly, we find significantly increased levels of eotaxin-1, eotaxin-2, and MMP-9 in blister fluids of BP patients. Taken together, this study establishes the eotaxin-1/CCR3 axis and MMP-9 as key players in anti-NC16A IgE-induced BP and candidate therapeutic targets for future drug development and testing.

Unusual clinical presentations of cutaneous squamous cell involving distal extremities in four patients: the importance of tissue sampling

INTRODUCTION

cSCC is the second most common cutaneous malignancy worldwide behind basal cell carcinoma. Typically, SCC is diagnosed early before it infiltrates local subcutaneous tissue or metastasizes. However, unusual presentations are possible and can lead to delayed treatment and possibly worse outcomes.

MATERIALS AND METHODS

All patients were White of non-Hispanic or Latino decent. Three-quarters of the cases were male, and a quarter female. The age range was 45 to 78 years. The documented sizes of lesions ranged from 6 cm to 10 cm in diameter. Three of the cases were initially diagnosed as nonhealing wounds, and one was diagnosed as cellulitis.

RESULTS

The authors observed that SCC can present unusually by mimicking nonhealing infected ulcers or skin infections such as cellulitis. Over 18 months, the authors' practice recorded 4 cases of cSCC that were initially treated as persistent infections, which potentially lead to worse outcomes.

CONCLUSION

These cases provide patterns and clues to potentially expedite the diagnosis and treatment of cSCC. Any skin lesion thought to be infectious but not responding to treatment should undergo tissue sampling.

Livedoid vasculopathy: A review with focus on terminology and pathogenesis

Livedoid vasculopathy (LV) is a rare thrombotic vasculopathy of the dermis characterized by painful, relapsing ulcers over the lower extremities. Diagnosis is challenging due to the overlap in clinical appearance and nomenclature with other skin disorders. Treatment selection is complicated by poor understanding of the pathogenesis of LV and lack of robust clinical trials evaluating therapy efficacy. The terminology and pathophysiology of LV are reviewed here, along with its epidemiology, clinical and histologic features, and treatment options. A diagnostic pathway is suggested to guide providers in evaluating for comorbidities, referring to appropriate specialists, and choosing from the available classes of therapy.

Characterization of the CpG Island Hypermethylated Phenotype Subclass in Primary Melanomas

Cutaneous melanoma can be lethal even if detected at an early stage. Epigenetic profiling may facilitate the identification of aggressive primary melanomas with unfavorable outcomes. We performed clustering of whole-genome methylation data to identify subclasses that were then assessed for survival, clinical features, methylation patterns, and biological pathways. Among 89 cutaneous primary invasive melanomas, we identified three methylation subclasses exhibiting low methylation, intermediate methylation, or hypermethylation of CpG islands, known as the CpG island methylator phenotype (CIMP). CIMP melanomas occurred as early as tumor stage 1b and, compared with low-methylation melanomas, were associated with age at diagnosis ≥65 years, lentigo maligna melanoma histologic subtype, presence of ulceration, higher American Joint Committee on Cancer stage and tumor stage, and lower tumor-infiltrating lymphocyte grade (all P < 0.05). Patients with CIMP melanomas had worse melanoma-specific survival (hazard ratio = 11.84; confidence interval = 4.65‒30.20) than those with low-methylation melanomas, adjusted for age, sex, American Joint Committee on Cancer stage, and tumor-infiltrating lymphocyte grade. Genes hypermethylated in CIMP compared with those in low-methylation melanomas included PTEN, VDR, PD-L1, TET2, and gene sets related to development/differentiation, the extracellular matrix, and immunity. CIMP melanomas exhibited hypermethylation of genes important in melanoma progression and tumor immunity, and although present in some early melanomas, CIMP was associated with worse survival independent of known prognostic factors.

Occult Rosacea Diagnosed After Recurring Blepharoplasty Incision Inflammation

We report an unusual case of a 58-year-old Caucasian female who developed intermittent eyelid erythema, edema, and wound thickening in the early postoperative period after bilateral upper eyelid blepharoplasty. These flares of inflammation sometimes appeared to respond to systemic antibiotics and steroid preparations and sometimes not. Because of concerns for possible mycobacterial infection, biopsy of the upper eyelid incision was performed and histopathology confirmed rosacea. Symptoms resolved with oral azithromycin. Our patient did not have a diagnosis of rosacea preoperatively. We believe that rosacea should be kept in mind in cases with either prolonged inflammation or recurrent inflammation in previously quiet eyelid incisions.

Non-Cell-Autonomous Activity of the Hemidesmosomal Protein BP180/Collagen XVII in Granulopoiesis in Humanized NC16A Mice

BP180 (also termed type XVII collagen) is a hemidesmosomal protein and plays a critical role in cell-cell matrix adhesion in the skin; however, its other biological functions are largely unclear. In this study, we generated a BP180 functional-deficient mouse strain by deleting its extracellular domain of humanized NC16A (termed ΔNC16A mice). We found that BP180 is expressed by bone marrow mesenchymal stem cells (BM-MSC), and its functional deficiency leads to myeloid hyperplasia. Altered granulopoiesis in ΔNC16A mice is through bone marrow stromal cells evidenced by bone marrow transplantation. Furthermore, the level of G-CSF in bone marrow and circulation were significantly increased in ΔNC16A mice as compared with wild-type mice. The increased G-CSF was accompanied by an increased activation of the NF-κB signaling pathway in bone marrow and BM-MSC of ΔNC16A mice. Blockade of G-CSF restored normal granulopoiesis in ΔNC16A mice. Inhibition of NF-κB signaling pathway significantly reduces the release of G-CSF from ΔNC16A BM-MSC in vitro and the level of serum G-CSF in ΔNC16A mice. To our knowledge, these findings provide the first direct evidence that BP180 plays an important role in granulopoiesis through regulating NF-κB signaling pathway in BM-MSC.

The dysfunction of BP180/collagen XVII in keratinocytes promotes melanoma progression

BP180, also termed collagen XVII, is a hemidesmosomal transmembrane glycoprotein expressed in basal keratinocytes, and functions as a cell-matrix adhesion molecule in the dermal-epidermal junction of the skin. Its function, other than cell-matrix adhesion, remains unclear. We generated a mouse strain with BP180 dysfunction (termed ∆NC16A), which develops spontaneous skin inflammation accompanied by an influx of myeloid derived suppressor cells (MDSCs). We used the B16 mouse melanoma model to demonstrate that BP180 dysfunction in either skin or basal keratinocytes promotes MDSC influx into skin and tumor progression. MDSC depletion reduced tumor progression in ∆NC16A mice, demonstrating a critical role for BP180 dysfunction-driven MDSCs in melanoma progression. This study provides the first direct evidence that BP180, a cell-cell matrix adhesion molecule, possesses antitumor function through modulating infiltration of MDSCs. Basal keratinocytes actively participate in skin microenvironment changes caused by BP180 dysfunction. ∆NC16A mice could be a new animal model to study the melanoma microenvironment.

Agreement of dermatopathologists in the evaluation of clinically difficult melanocytic lesions: how golden is the 'gold standard'?

BACKGROUND

The 'gold standard' for the diagnosis of melanocytic lesions is dermatopathology. Although most of the diagnostic criteria are clearly defined, the interpretation of histopathology slides may be subject to interobserver variability.

OBJECTIVES

The aim of this study was to determine the variability among dermatopathologists in the interpretation of clinically difficult melanocytic lesions.

METHODS

This study used the database of MelaFind®, a computer-vision system for the diagnosis of melanoma. All lesions were surgically removed and sent for independent evaluation by four dermatopathologists. Agreement was calculated using kappa statistics.

RESULTS

A total of 1,249 pigmented melanocytic lesions were included. There was a substantial agreement among expert dermatopathologists: two-category kappa was 0.80 (melanoma vs. non-melanoma) and three-category kappa was 0.62 (malignant vs. borderline vs. benign melanocytic lesions). The agreement was significantly greater for patients ≥40 years (three-category kappa = 0.67) than for younger patients (kappa = 0.49). In addition, the agreement was significantly lower for patients with atypical mole syndrome (AMS) (kappa = 0.31) than for patients without AMS (kappa = 0.76).

LIMITATIONS

The data were limited by the inclusion/exclusion criteria of the MelaFind® study. This might represent a selection bias. The agreement was evaluated using kappa statistics. This is a standard method for evaluating agreement among pathologists, but might be considered controversial by some statisticians.

CONCLUSIONS

Expert dermatopathologists have a high level of agreement when diagnosing clinically difficult melanocytic lesions. However, even among expert dermatopathologists, the current 'gold standard' is not perfect. Our results indicate that lesions from younger patients and patients with AMS may be more problematic for the dermatopathologists, suggesting that improved diagnostic criteria are needed for such patients.

A dual role for the immune response in a mouse model of inflammation-associated lung cancer

Lung cancer is the leading cause of cancer death worldwide. Both principal factors known to cause lung cancer, cigarette smoke and asbestos, induce pulmonary inflammation, and pulmonary inflammation has recently been implicated in several murine models of lung cancer. To further investigate the role of inflammation in the development of lung cancer, we generated mice with combined loss of IFN-γ and the β-common cytokines GM-CSF and IL-3. These immunodeficient mice develop chronic pulmonary inflammation and lung tumors at a high frequency. Examination of the relationship between these tumors and their inflammatory microenvironment revealed a dual role for the immune system in tumor development. The inflammatory cytokine IL-6 promoted optimal tumor growth, yet wild-type mice rejected transplanted tumors through the induction of adaptive immunity. These findings suggest a model whereby cytokine deficiency leads to oncogenic inflammation that combines with defective antitumor immunity to promote lung tumor formation, representing a unique system for studying the role of the immune system in lung tumor development.

The performance of MelaFind: a prospective multicenter study

OBJECTIVE

To demonstrate the safety and effectiveness of MelaFind, a noninvasive and objective computer-vision system designed to aid in detection of early pigmented cutaneous melanoma.

DESIGN

A prospective, multicenter, blinded study. The diagnostic performance of MelaFind and of study clinicians was evaluated using the histologic reference standard. Standard images and patient information for a subset of 50 randomly selected lesions (25 melanomas) were used in a reader study of 39 independent dermatologists to estimate clinicians' biopsy sensitivity to melanoma.

SETTING

Three academic and 4 community practices in the United States with expertise in management of pigmented skin lesions.

PATIENTS

A total of 1383 patients with 1831 lesions enrolled from January 2007 to July 2008; 1632 lesions (including 127 melanomas-45% in situ-with median Breslow thickness of invasive lesions, 0.36 mm) were eligible and evaluable for the study end points.

MAIN OUTCOME MEASURES

Sensitivity of MelaFind; specificities and biopsy ratios for MelaFind and the study investigators; and biopsy sensitivities of independent dermatologists in the reader study.

RESULTS

The measured sensitivity of MelaFind was 98.4% (125 of 127 melanomas) with a 95% lower confidence bound at 95.6% and a biopsy ratio of 10.8:1; the average biopsy sensitivity of dermatologists was 78% in the reader study. Including borderline lesions (high-grade dysplastic nevi, atypical melanocytic proliferations, or hyperplasias), MelaFind's sensitivity was 98.3% (172 of 175), with a biopsy ratio of 7.6:1. On lesions biopsied mostly to rule out melanoma, MelaFind's average specificity (9.9%) was superior to that of clinicians (3.7%) (P=.02).

CONCLUSION

MelaFind is a safe and effective tool to assist in the evaluation of pigmented skin lesions.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT00434057.

The diagnostic performance of expert dermoscopists vs a computer-vision system on small-diameter melanomas

OBJECTIVE

To evaluate the performance of dermoscopists in diagnosing small pigmented skin lesions (diameter </= 6 mm) compared with an automatic multispectral computer-vision system.

DESIGN

Blinded comparison study.

SETTING

Dermatologic hospital-based clinics and private practice offices. Patients From a computerized skin imaging database of 990 small (</= 6-mm) pigmented skin lesions, all 49 melanomas from 49 patients were included in this study. Fifty randomly selected nonmelanomas from 46 patients served as a control.

MAIN OUTCOME MEASURES

Ten dermoscopists independently examined dermoscopic images of 99 pigmented skin lesions and decided whether they identified the lesions as melanoma and whether they would recommend biopsy to rule out melanoma. Diagnostic and biopsy sensitivity and specificity were computed and then compared with the results of the computer-vision system.

RESULTS

Dermoscopists were able to correctly identify small melanomas with an average diagnostic sensitivity of 39% and a specificity of 82% and recommended small melanomas for biopsy with a sensitivity of 71% and specificity of 49%, with only fair interobserver agreement (kappa = 0.31 for diagnosis and 0.34 for biopsy). In comparison, in recommending biopsy to rule out melanoma, the computer-vision system achieved 98% sensitivity and 44% specificity.

CONCLUSIONS

Differentiation of small melanomas from small benign pigmented lesions challenges even expert physicians. Computer-vision systems can facilitate early detection of small melanomas and may limit the number of biopsies to rule out melanoma performed on benign lesions.

Primary angiosarcoma of the spleen: a case report and review of the literature

We describe a 47-year-old man with shoulder pain, multiple bony lesions, and a 1-cm lesion in the spleen. T-1 facetectomy revealed a poorly differentiated malignant neoplasm. Several months after chemotherapy, multiple splenic lesions were found by computed tomography and liver-spleen scan. A splenectomy showed a malignant spindle-cell neoplasm forming irregular vascular spaces. Tumor cells were positive for factor VIII-related antigen and vimentin. This patient died of extensive metastases from this primary angiosarcoma of the spleen. Splenic angiosarcoma is a rare neoplasm that often has a cryptic presentation and a dismal prognosis.

Angiolymphoid hyperplasia with eosinophilia (histiocytoid hemangioma): evaluation of treatment options

Angiolymphoid hyperplasia with eosinophilia is an uncommon benign vascular proliferative lesion of unknown cause. In this report, a case is presented of a patient who was confirmed to be positive for human immunodeficiency virus and in whom the lesion had shown rapid accelerated growth. The case is used to illustrate a variety of therapeutic techniques and to evaluate the effectiveness of the various alternatives in the treatment of this unusual clinical problem. Long-term follow-up after radical excision of the tumor mass is presented.