The Immunogenetics of Autoimmune Blistering Diseases.

Dermatological conditions constituting the group of autoimmune blistering diseases (AIBD) are characterized by loss of immunotolerance and humoral, as well as cellular, autoimmune responses that result in the development of bullae and erosions on the skin and mucous membranes. AIBDs are broadly categorized into pemphigus and pemphigoid classes with several distinct subtypes amongst them. Advances in genetics have allowed for the study and identification of alleles, and even single nucleotide polymorphisms, that harbor increased susceptibility or confer protection for the development of these conditions. The focus of this chapter pertains to a comprehensive review of the known genetic associations with AIBDs, including HLA class I-III, as well as non-HLA genes and non-coding sequences that influence cellular processes and signaling pathways.

Digital Quantification of Epidermal Protein Expression in Paraffin-Embedded Tissue Using Immunohistochemistry.

Current methods of assessing immunohistochemistry center on semiquantitative visual grading scales. More objective methods utilizing digital quantification offer superior precision and, presumably, higher confidence with image comparison. However, their cost often remains prohibitive, and there is little customizability to separate subsections of interest in the tissue. Here we describe a method using two open-source software programs to analyze the intensity and density of signals in immunohistochemistry-stained tissue sections that account for tissue heterogeneity and allow for direct comparison between two samples. This method allows for quantitative assessment of epidermal protein expression. We herein demonstrate this workflow using an epidermal stain tothymic stromal lymphopoietin.

Epidermal expression of eotaxins and thymic stromal lymphopoietin in eosinophil rich dermatoses.

Eosinophils are seen in a number of dermatologic conditions. While the extent of their function in these diseases remains to be fully elucidated, pathogenic activity in bullous pemphigoid suggests a more significant role than previously thought. Several dermatoses have a fairly characteristic histologic morphology of eosinophil infiltration. We hypothesized that epidermal expression of eotaxins and TSLP would differ by disease, perhaps explaining the different histologic morphologies. We performed a retrospective study of eosinophil rich dermatoses to perform immunohistochemistry. We collected 49 specimens composed of bullous pemphigoid (n = 15), atopic dermatitis (n = 12), drug rash (n = 8), arthropod assault (n = 5), and non-bullous pemphigoid eosinophilic spongiosis (n = 5). We used lichen planus (n = 4) as a control for lymphocyte-mediated inflammation. TSLP was diffusely expressed in all epidermal samples, whereas eotaxins demonstrated a weaker staining. Eotaxins and TSLP demonstrated a gradient between basal and spinous keratinocytes. The correlation between overall basal keratinocyte and spinous keratinocyte staining of eotaxins and TSLP with the number of eosinophils demonstrated a significant correlation between eotaxin-1 (R = 0.404, P = 0.004), eotaxin-2 (R = 0.576, P < 0.001), and eotaxin-3 (R = 0.512, P < 0.001), but not TSLP (R = 0.164, P = 0.251). These remained significant after correcting for multiple comparisons. While we were unable to detect significant differences in epidermal expression of eotaxins and TSLP in various eosinophil rich dermatoses, we identified a significant correlation of spinous keratinocyte eotaxin staining with tissue eosinophilia. Our identification of a correlation of spinous keratinocyte eotaxin staining with tissue eosinophilia may provide insight into local eosinophil chemotaxis.

Epidermolysis bullosa acquisita: A comprehensive review.

Epidermolysis bullosa acquisita is a rare autoimmune blistering disease which results in vesicle and bullae formation on the skin and erosions on the mucous membranes. EBA is mediated by autoantibodies to collagen VII. Clinically, it can present with numerous phenotypes, though the most common are the mechanobullous and inflammatory variants. Patients with mechanobullous EBA develop non-inflammatory bullae and erosions at sites of trauma while patients with the non-mechanobullous type develop inflammatory lesions which often mimic other blistering conditions including bullous pemphigoid, linear IgA bullous disease, and mucous membrane pemphigoid. Diagnosis is established by having a consistent clinical presentation, DIF, and autoantibodies against collagen VII. In apparent "seronegative" patients, the diagnosis is challenging due to the need for confirmatory tests which are often not routinely accessible outside of the specialized center. In light of EBA's rarity, and lack of any randomized controlled trials, treatment guidelines rely on the small case series presented in the literature. There has been variable success utilizing the arsenal of immunosuppressants and biologics. Development of experimental murine models has facilitated a deeper understanding of EBA's pathogenesis and allows for preclinical testing of numerous novel drug targets predominantly targeting inhibition of neutrophil activation. We herein review the presentation, diagnosis, treatments, and future avenues of research in EBA.

Treatment-resistant prurigo nodularis: challenges and solutions.

Prurigo nodualris (PN) is a chronic condition with highly pruritic, hyperkeratotic papules or nodules arising in the setting of chronic pruritus. While PN may serve as a phenotypic presentation of several underlying conditions such as atopic dermatitis, chronic kidney disease-related pruritus, and neurological diseases, it represents a distinct clinical entity that may persist despite the removal of the underlying cause, if one is identified. Neuronal proliferation, eosinophils, mast cells, and small-fiber neuropathy play a role in the production of pruritus in PN, although the exact mechanism has not yet been established. Identifying an underlying cause, if present, is essential to prevent recurrence of PN. Due to often present comorbidities, treatment is typically multimodal with utilization of topical and systemic therapies. We performed a PubMed/MEDLINE search for PN and present a review of recent developments in the treatment of PN. Treatment typically relies on the use of topical or intralesional steroids, though more severe or recalcitrant cases often necessitate the use of phototherapy or systemic immunosuppressives. Thalidomide and lenalidomide can both be used in severe cases; however, their toxicity profile makes them less favorable. Opioid receptor antagonists and neurokinin-1 receptor antagonists represent two novel families of therapeutic agents which may effectively treat PN with a lower toxicity profile than thalidomide or lenalidomide.

Serum and blister fluid levels of cytokines and chemokines in pemphigus and bullous pemphigoid.

Bullous pemphigoid and pemphigus constitute two major autoimmune blistering diseases (AIBD) with complicated disease pathomechanisms involving a multitude of cytokines and immunological pathways. The purpose of our literature review of the cytokines and chemokines involved in these AIBDs was to allow for a meta-analysis of studies detailing differential cytokine and chemokine changes in these conditions. Elucidation of inflammatory pathways could lead to more targeted therapies, several of which specific monoclonal antibodies already exist and are used safely for other autoimmune diseases. A systematic review of the Pubmed/Medline database was performed for articles characterizing cytokines/chemokines involved in BP and pemphigus. Further, a meta-analysis was carried out using standardized methods, including assessment for heterogeneity. The results of our analysis demonstrated numerous inflammatory alterations in these AIBDs. Significant alterations included serum levels of IL-5, IL-6, IL-8, IL-17, CCL-17, and CCL-26 in patients with BP, and increased blister fluids levels of IL-5, IL-6, IL-8, CCL11, and TNF-α. Blister fluid levels of IL-1α are decreased in BP. In pemphigus, we identified significantly increased serum levels of IL-10, IL-17, and CCL17. We have additionally summarized all studies excluded from meta-analysis to provide a comprehensive summary of cytokine/chemokine alterations in these two conditions.

Effect of Endoscopic Bronchial Ultrasound on Outcomes for Stage I Non-Small-Cell Lung Cancer Patients Receiving Hypofractionated Radiotherapy.

BACKGROUND: In this study we sought to determine if staging endoscopic bronchial ultrasound (EBUS) improves outcomes in stage I non-small-cell lung cancer (NSCLC) patients who received hypofractionated radiation therapy (HFRT). PATIENTS AND METHODS: Patients with stage I NSCLC treated with HFRT from 2008 to 2015 were retrospectively identified from 3 affiliated institutions. All patients underwent positron emission tomography/computed tomography staging and a subset of patients received pretreatment EBUS. Patients with and without pre-radiation therapy EBUS were compared for baseline characteristics. The log rank test was used to compare Kaplan-Meier estimates. Univariate analysis (UVA) and multivariable analysis (MVA) were used to analyze the effect of factors on disease-free survival (DFS) and overall survival (OS). RESULTS: Ninety-two patients met study criteria. Median follow-up for the entire cohort was 21 months. Two-year DFS and OS were 63% and 81%, respectively. Two-year freedom from local, regional, and distant failure were 93%, 87%, and 87%, respectively. Thirty-seven of 92 patients (40%) received pretreatment EBUS. There were no statistically significant differences in 2-year freedom from regional failure rates, DFS, or OS for EBUS-staged versus non-EBUS-staged patients. On UVA, smaller tumor size (P = .03) and higher performance status (P = .05) were associated with improved OS. On MVA, tumor size retained significance for improved OS (hazard ratio [HR], 0.44; 95% confidence interval [CI], 0.19-0.97; P = .04) and higher performance status showed a trend toward improved OS (HR, 0.51; 95% CI, 0.23-1.11; P = .09). CONCLUSION: In this retrospective series, we did not detect a difference in regional failure or survival outcomes among stage I NSCLC patients who received invasive staging with EBUS before HFRT.