Eczema vaccinatum is a potentially fatal, disseminated viral skin infection that develops in indi... more Eczema vaccinatum is a potentially fatal, disseminated viral skin infection that develops in individuals with atopic dermatitis after exposure to the vaccinia virus (VV). Despite advances in modern medicine, there are few options for those suffering from disseminated VV infections. Ceragenins (CSAs) are synthetic antimicrobial compounds designed to mimic the structure and function of endogenous antimicrobial peptides (AMPs). We show that CSA-13 exhibits potent antiviral activity against VV by (1) direct antiviral effects against VV; and (2) stimulating the expression of endogenous AMPs with known antiviral activity against VV. In addition, we show that a topical application of CSA-13 penetrates the skin and reduces subsequent satellite lesion formation. This suggests that treatment with CSA-13 may be an intervention for individuals with a disseminated VV skin infection.
The Journal of Allergy and Clinical Immunology, Apr 1, 2007
Atopic dermatitis (AD) is a chronic inflammatory skin disorder that is associated with recurrent ... more Atopic dermatitis (AD) is a chronic inflammatory skin disorder that is associated with recurrent bacterial and viral skin infections. 1 This has prompted the Center for Disease Control and Prevention (CDC) to exclude individuals with AD from smallpox vaccination with vaccinia virus (VV) due to the increased risk of developing eczema vaccinatum. Anti-microbial peptides (AMPs) are an integral component of the innate immune response due to their activity against invading pathogens. 2,3 Recent studies by our laboratory have demonstrated that two main families of AMPs-β-defensins and cathelicidins-are deficient in the skin of AD patients. 4,5 This deficiency may explain, in part, the increased propensity of AD patients to recurrent skin infections.
Although much data has been obtained related to the clinical manifestations of latex allergy and ... more Although much data has been obtained related to the clinical manifestations of latex allergy and the characterization of the protein allergens, little is known regarding the natural history of the disease. These studies were undertaken to demonstrate the immunological relevance of both dermal and respiratory exposure in the development of latex allergy and to investigate the role of co-exposure by these routes to other agents in the health care environment on the development of NRL sensitization. An initial study in female BALB/c mice demonstrated comparable rates of induction of latex specific IgE following dermal and respiratory latex exposure, demonstrating the importance of both routes in the development of latex allergy. Upon further investigation using whole body plethysmography, non-specific airway hyperreactivity to methacholine was observed in mice following both dermal and intratracheal sensitization with latex proteins. In contrast, at these exposure levels latex specific airway hyper-reactivity was only observed in dermally sensitized mice. Endotoxin, a common contaminant of powdered gloves, and glutaraldehyde, a frequently used cold sterilant, were chosen to investigate the immunomodulatory effects of other agents in the health care setting on the development of latex allergy. In comparison with mice exposed to latex alone, mice concurrently exposed to latex and increasing concentrations of endotoxin demonstrated ~50% lower levels of latex specific IgE and a decrease in latex specific airway hyper-reactivity and mucin production. The same animals demonstrated increased levels of latex specific IgG2a and IgA, cellular infiltration (i.e. macrophages and neutrophils) into the peribronchial and perivascular regions of the lung, messenger IFN-γ and IL-12 levels in the draining mediastinal lymph nodes, and non-specific airway hyper-reactivity upon respiratory challenge with methacholine. Upon concurrent dermal exposure to latex and concentrations of glutaraldehyde surrounding the permissible exposure limit, mice demonstrated a dose responsive increase in latex specific IgE levels through an as yet undetermined mechanism. These studies demonstrate the potential for mixed exposures in the health care environment to diversely modulate the development of IgE mediated responses to NRL proteins underscoring the importance of environmental factors in the development of allergies to foreign antigens. iii ACKNOWLEDGEMENTS To my advisor, mentor and friend, Dr. Barbara Jean Meade, for her knowledge, support, discipline, motivation and persistence in helping me grow as a scientist. To Dr. Albert E. Munson for always stimulating the mind to understand both the question and answer in all of science and life. To Drs. Christopher Cuff, Daniel Lewis, and Rosana Schafer for supporting me through out the course of my training and offering valuable insight into my research. To my predecessors, Drs. Michael Woolhiser, Scott Manetz, and Ben Hayes, for their direction, assistance, patience and advice during my early years in the laboratory. To friends along the way who have helped mold me both scientifically and personally throughout my stay in Morgantown. To Kurt Brumbaugh for his friendship, support through life experiences, and constant nagging about proper statistical analysis. To Melanie Flint (Crazy Brit) for both scientific stimulation and comic relief. To Kim Klink for scientific discussion, analysis of artificial precipitation, and humor. To Ashley Murray for being by my side, supporting me, and helping me maintain my sanity through the final stages of my dissertation and experiences ahead. To all of the staff at NIOSH who assisted me during the course of my education and research with special thanks to Leon Butterworth, Shahla Azadi, Beverly Fragale, Kim Collins, and the Pathology group. And most importantly, to my family, not only because they gave birth to me, but also because they have always told me to shoot for the stars and have supported me every step of the way.
The Journal of Allergy and Clinical Immunology, 2010
Background-Eczema vaccinatum (EV), a disseminated viral skin infection, is a life threatening com... more Background-Eczema vaccinatum (EV), a disseminated viral skin infection, is a life threatening complication of vaccinia virus (VV) inoculation in patients with atopic dermatitis (AD) and is thought to be associated with a defective innate immune response. However, the precise mechanism(s) and key factor(s) of EV are unknown. Objective-Given that patients with psoriasis, another inflammatory skin disorder, are not susceptible to EV, we compared the global transcriptional response of skin to VV in healthy, psoriatic, and AD individuals focusing on AD specific genes. We hypothesized that differences in the transcriptional response to VV between AD and psoriatic or healthy individuals would identify a defective pathway(s) that might be associated with the development of EV. Methods-Gene expression profiling of sham-treated and VV-treated unaffected skin explants from AD (n=12), psoriatic (n=12), or healthy (n=13) individuals were generated using U133_Plus2 (54613 probe sets) GeneChips and analyzed using GCOS_1.4/SAM_2.1/MAPPFinder_2.0 pipeline. Results-Sixty-seven genes were significantly affected by VV in AD, but not in psoriatic and healthy skin. Genes associated with defense response, response to wounding, and immune response were the most affected by VV in AD skin. All genes in these ontologies were downregulated including innate immunity genes LTB4R, ORM1, F2R, C9, and LBP. These findings were confirmed by real-time PCR and validated by PubMatrix analysis. ORM1, TLR4, and NLRP1 were also linked to AD severity. Conclusion-This study identified groups of innate immunity genes that are associated with the aberrant response of AD skin to VV and represent potential targets for EV pathogenesis.
Candida albicans (CA) infections have been associated with psoriasis onset or disease flares. How... more Candida albicans (CA) infections have been associated with psoriasis onset or disease flares. However, the integrated immune response against this fungus is still poorly characterized in psoriasis. We studied specific immunoglobulins in plasma and the CA response in cocultures of circulating memory CD45RA− cutaneous lymphocyte antigen (CLA)+/− T cell with autologous epidermal cells from plaque and guttate psoriasis patients (cohort 1, n = 52), and also healthy individuals (n = 17). A complete proteomic profile was also evaluated in plaque psoriasis patients (cohort 2, n = 114) regarding their anti-CA IgA levels. Increased anti-CA IgA and IgG levels are present in the plasma from plaque but not guttate psoriasis compared to healthy controls. CA cellular response is confined to CLA+ T cells and is primarily Th17. The levels of anti-CA IgA are directly associated with CLA+ Th17 response in plaque psoriasis. Proteomic analysis revealed distinct profiles in psoriasis patients with high a...
Objective Hidradenitis suppurativa (HS) is a chronic inflammatory disease with limited treatment ... more Objective Hidradenitis suppurativa (HS) is a chronic inflammatory disease with limited treatment options; therefore, the current study investigated the downstream signaling pathways that are differentially expressed in HS subjects and may drive disease pathogenesis. Methods The expression of 144 genes was evaluated in the skin of 16 healthy subjects and 34 subjects with mild to severe HS using QuantiGene Plex assay. Results One hundred and twenty-nine genes were significantly elevated in lesional HS skin as compared to the skin of healthy controls including pro-inflammatory cytokines (IL-1α, IL-6, TNF-α), IL-17-associated cytokines (IL-17A, IL-17F, IL-23A), the IL-10 family of cytokines (IL-10, IL-19, IL-20, IL-22, IL-24), and IFN family members (IFNA1, IFNB1, IFNG, IL-12B). This corresponded with increased expression of tyrosine kinases (JAK1, JAK3, BTK, SYK) and their downstream signaling partners (STAT1, STAT2, STAT3, STAT5A, STAT5B, STAT6). Conclusion These data illustrate the diverse immune activation in lesional HS skin and suggest that deeper interrogation of the disease heterogeneity may reveal unique opportunities for targeted therapies in designated subpopulations.
Background: Atopic dermatitis (AD) is a highly pruritic chronic inflammatory skin disorder. Ruxol... more Background: Atopic dermatitis (AD) is a highly pruritic chronic inflammatory skin disorder. Ruxolitinib, a selective inhibitor of Janus kinase 1 and Janus kinase 2, potently suppresses cytokine signaling involved in AD pathogenesis.
Autoimmune skin diseases are characterized by significant local and systemic inflammation that is... more Autoimmune skin diseases are characterized by significant local and systemic inflammation that is largely mediated by the Janus kinase (JAK)-signal transducer and activator of transcription (STAT) pathway. Advanced understanding of this pathway has led to the development of targeted inhibitors of Janus kinases (JAKinibs). As a class, JAK inhibitors effectively treat a multitude of hematologic and inflammatory diseases. Growing evidence suggests that JAK inhibitors are efficacious in atopic dermatitis, alopecia areata, psoriasis, and vitiligo. Additional evidence suggests that JAK inhibition might be broadly useful in dermatology, with early reports of efficacy in several other conditions. JAK inhibitors can be administered orally or used topically and represent a promising new class of medications. Here we review the evolving data on the role of the JAK-STAT pathway in inflammatory dermatoses and the potential therapeutic benefit of JAK-STAT antagonism.
Hidradenitis suppurativa (HS) is a chronic skin disease of the pilo-sebaceous apocrine unit chara... more Hidradenitis suppurativa (HS) is a chronic skin disease of the pilo-sebaceous apocrine unit characterized by significant inflammation and an impaired quality of life. The pathogenesis of HS remains unclear. To determine the HS skin and blood transcriptomes and HS blood proteome, patient data from previously published studies were analysed and integrated from a cohort of patients with moderate to severe HS (n = 17) compared to healthy volunteers (n = 10). The analysis utilized empirical Bayes methods to determine differentially expressed genes (DEGs) (fold change (FCH) >2.0 and false discovery rate (FDR) <0.05), and differentially expressed proteins (DEPs) (FCH>1.5, FDR<0.05). In the HS skin transcriptome (lesional skin compared to non-lesional skin), there was an abundance of immunoglobulins, antimicrobial peptides, and an interferon signature. Gene-sets related to Notch signalling and Interferon pathways were differentially activated in lesional compared to non-lesional...
Background: IL-13 has an important role in atopic dermatitis (AD) pathogenesis. Tralokinumab is a... more Background: IL-13 has an important role in atopic dermatitis (AD) pathogenesis. Tralokinumab is a fully human mAb that potently and specifically neutralizes IL-13. Objective: We sought to evaluate the efficacy and safety of tralokinumab in adults with moderate-to-severe AD. Methods: In this phase 2b study (NCT02347176), 204 adults were randomized 1:1:1:1 to receive 45, 150, or 300 mg of subcutaneous tralokinumab, or placebo, every 2 weeks for 12 weeks with concomitant topical glucocorticoids. Coprimary end points were change from baseline in Eczema Area Severity Index score and percentage of participants with an Investigator's Global Assessment response (0/1 score and reduction of > _2 grades from baseline) at week 12. Results: At week 12, 300 mg of tralokinumab significantly improved change from baseline in Eczema Area Severity Index score versus placebo (adjusted mean difference, 24.94; 95% CI, 28.76 to 21.13; P 5 .01), and a greater percentage of participants achieved an Investigator's Global Assessment response (26.7% vs 11.8%). Greater responses were found in participants with greater concentrations of biomarkers of increased IL-13 activity. Participants treated with 300 mg of tralokinumab demonstrated improvements in SCORAD, Dermatology Life Quality Index, and pruritus numeric rating scale (7-day mean) scores versus placebo. Upper respiratory tract infection was the most frequent treatment-emergent adverse event reported as related to study drug in the placebo (3.9%) and pooled tralokinumab (3.9%) groups. Conclusions: Tralokinumab treatment was associated with early and sustained improvements in AD symptoms and an acceptable safety and tolerability profile, thereby providing evidence for targeting IL-13 in patients with AD.
Clinical and experimental allergy : journal of the British Society for Allergy and Clinical Immunology, Jan 13, 2017
Atopic dermatitis (AD), psoriasis (PS), and contact dermatitis (CD) are common skin diseases, cha... more Atopic dermatitis (AD), psoriasis (PS), and contact dermatitis (CD) are common skin diseases, characterized by barrier disruption and systemic inflammation, with unique epidermal signatures and common inflammatory pathways identified by transcriptomic profiling. This study profiled proteomic signatures in serum from subjects with AD, PS, and CD compared with healthy controls (HC). Identify unique proteomic signatures to distinguish between inflammatory diseases with similar epidermal disruption and overlapping epithelial inflammation. Sera from 20 subjects with moderate to severe AD, 10 subjects with CD, 12 subjects with moderate to severe PS, 10 subjects with both AD and CD, and 10 HC with no history of skin disease was analyzed using high throughput proteomic analysis that detects expression of 1129 protein targets. Protein expression was compared between disease and HC, and across diseases for statistical significance (fold change ≥1.5 and false discovery rate ≤0.05), to identify...
International Archives of Allergy and Immunology, 2016
Atopic dermatitis (AD) is a chronic inflammatory skin disease that affects up to 25% of children ... more Atopic dermatitis (AD) is a chronic inflammatory skin disease that affects up to 25% of children and 10% of adults. The skin of patients with moderate to severe AD is characterized by significant barrier disruption and T helper 2 (Th2)-driven inflammation, which are thought to play a significant role in the pathogenesis of AD. Current management of AD is aimed at suppressing the inflammatory response and restoring the barrier function of the skin, reducing exacerbations, and preventing secondary skin infections. Combinations of treatment strategies are used to alleviate the symptoms of the disease; however, resolution is often temporary, and long-term usage of some of the medications for AD can be associated with significant side effects. Antibody therapies previously approved for other inflammatory diseases have been evaluated in patients with AD. Unfortunately, they have often failed to result in significant clinical improvement. Monoclonal antibodies and novel small molecules cur...
Proceedings of the National Academy of Sciences, 2009
Eczema vaccinatum (EV) is a complication of smallpox vaccination occurring in patients with atopi... more Eczema vaccinatum (EV) is a complication of smallpox vaccination occurring in patients with atopic dermatitis. In affected individuals, vaccinia virus (VV) spreads through the skin, resulting in large primary lesions and satellite lesions, and infects internal organs. BALB/c mice inoculated with VV at sites of Th2-biased allergic skin inflammation elicited by epicutaneous ovalbumin (OVA) sensitization exhibited larger primary lesions that were erosive, more satellite lesions, and higher viral loads in skin and internal organs than mice inoculated in saline-exposed skin, unsensitized skin, or skin sites with Th1-dominant inflammation. VV inoculation in OVA-sensitized skin induced marked local expression of IL-17 transcripts and massive neutrophil infiltration compared to VV inoculation in saline-exposed skin. Treatment with anti-IL-17 decreased the size of primary lesions, numbers of satellite lesions, and viral loads. Addition of IL-17 promoted VV replication in skin explants. These...
Recurrent skin infections in extrinsic atopic dermatitis (EAD) may be because of the suppression ... more Recurrent skin infections in extrinsic atopic dermatitis (EAD) may be because of the suppression of anti-microbial peptide (AMP) expression by interleukin (IL)-4 and IL-13. Twenty to thirty percent of AD, however, are classified as intrinsic atopic dermatitis (IAD). They exhibit normal serum IgE levels, no allergen-specific sensitization, and lower levels of IL-4 and IL-13 than EAD. Both forms of AD have increased propensity to skin infection, suggesting a novel mechanism for infection in IAD. In this study, we observed significantly decreased human b-defensin (HBD)-2 gene expression in the skin of both IAD (p ¼ 0.010) and EAD (p ¼ 0.004), as compared with psoriasis patients. Conversely, IAD (p ¼ 0.019) and EAD (p ¼ 0.002) skin lesions exhibited elevated IL-10 gene expression when compared with psoriasis. Using primary keratinocytes, we found that the deficiency in AMP expression is an acquired rather than a constitutive defect. Interestingly, neutralizing antibodies to IL-10 augmented the production of tumor necrosis factor-a and interferon-c by peripheral blood mononuclear cell from AD patients. Additionally, treatment of AD skin explants with anti-IL-10 augmented the expression of both HBD-2 and LL-37. Thus, increased levels of IL-10 may contribute to the AMP deficiency in both IAD and EAD by reducing cytokines that induce AMP.
Eczema vaccinatum is a potentially fatal, disseminated viral skin infection that develops in indi... more Eczema vaccinatum is a potentially fatal, disseminated viral skin infection that develops in individuals with atopic dermatitis after exposure to the vaccinia virus (VV). Despite advances in modern medicine, there are few options for those suffering from disseminated VV infections. Ceragenins (CSAs) are synthetic antimicrobial compounds designed to mimic the structure and function of endogenous antimicrobial peptides (AMPs). We show that CSA-13 exhibits potent antiviral activity against VV by (1) direct antiviral effects against VV; and (2) stimulating the expression of endogenous AMPs with known antiviral activity against VV. In addition, we show that a topical application of CSA-13 penetrates the skin and reduces subsequent satellite lesion formation. This suggests that treatment with CSA-13 may be an intervention for individuals with a disseminated VV skin infection.
Atopic dermatitis (AD) and psoriasis are the two most common chronic skin diseases. However patie... more Atopic dermatitis (AD) and psoriasis are the two most common chronic skin diseases. However patients with AD, but not psoriasis, suffer from frequent skin infections. To understand the molecular basis for this phenomenon, skin biopsies from AD and psoriasis patients were analyzed using GeneChip microarrays. The expression of innate immune response genes, human β defensin (HBD)-2, IL-8, and inducible NO synthetase (iNOS) was found to be decreased in AD, as compared with psoriasis, skin (HBD-2, p = 0.00021; IL-8, p = 0.044; iNOS, p = 0.016). Decreased expression of the novel antimicrobial peptide, HBD-3, was demonstrated at the mRNA level by real-time PCR (p = 0.0002) and at the protein level by immunohistochemistry (p = 0.0005). By real-time PCR, our data confirmed that AD, as compared with psoriasis, is associated with elevated skin production of Th2 cytokines and low levels of proinflammatory cytokines such as TNF-α, IFN-γ, and IL-1β. Because HBD-2, IL-8, and iNOS are known to be i...
Human β-defensins (HBDs) are a major class of antimicrobial peptides that play an important role ... more Human β-defensins (HBDs) are a major class of antimicrobial peptides that play an important role in the innate immune response, however, the induction and regulation of these antimicrobial peptides is not well understood. We demonstrate here that stimulation of keratinocytes with TNF-α/IFN-γ induces HBD-2 and HBD-3 by activating STAT-1 and NF-κB signaling. We further demonstrate that IL-4 and IL-13 activate STAT-6 and induce the suppressors of cytokine signaling (SOCS)-1 and -3. This interferes with STAT-1 and NF-κB signaling, thereby inhibiting TNF-α/IFN-γ-mediated induction of HBD-2 and HBD-3. These data suggest that targeting the STAT-1-signaling pathway or suppressor of cytokine signaling expression enhances β-defensin expression and represents a new therapeutic strategy for reduction of infection in human diseases associated with β-defensin deficiency.
Atopic dermatitis (AD) is an inflammatory skin disease associated with frequent skin infection an... more Atopic dermatitis (AD) is an inflammatory skin disease associated with frequent skin infection and impaired skin barrier function. Recent studies indicate that increased Th2 cytokine expression contributes to reduction in antimicrobial peptides and reduced filaggrin (FLG) expression, however, the mechanisms leading to this effect is unknown. Using proteomics, we found the S100 calcium-binding protein A11 (S100/A11) to be significantly downregulated in the presence of IL-4 and IL-13. Culturing keratinocytes with increased calcium concentrations significantly induced S100/A11 expression. This corresponded with an increase in human b-defensin (HBD)-3 and FLG expression. Interference of S100/A11 expression, by siRNA, inhibited induction of HBD-3 and FLG. Furthermore p21, a cyclin-dependent kinase inhibitor downstream of S100/A11, was required for calciummediated induction of HBD-3 and FLG. Importantly, transduction of p21-recombinant protein into keratinocytes prevented IL-4/IL-13-mediated inhibition of FLG and HBD-3 expression. S100/A11 and p21 gene expression was also found to be significantly lower in acute and chronic AD skin. This study demonstrates an important role for S100/A11 and p21 in regulating skin barrier integrity and the innate immune response.
Eczema vaccinatum is a potentially fatal, disseminated viral skin infection that develops in indi... more Eczema vaccinatum is a potentially fatal, disseminated viral skin infection that develops in individuals with atopic dermatitis after exposure to the vaccinia virus (VV). Despite advances in modern medicine, there are few options for those suffering from disseminated VV infections. Ceragenins (CSAs) are synthetic antimicrobial compounds designed to mimic the structure and function of endogenous antimicrobial peptides (AMPs). We show that CSA-13 exhibits potent antiviral activity against VV by (1) direct antiviral effects against VV; and (2) stimulating the expression of endogenous AMPs with known antiviral activity against VV. In addition, we show that a topical application of CSA-13 penetrates the skin and reduces subsequent satellite lesion formation. This suggests that treatment with CSA-13 may be an intervention for individuals with a disseminated VV skin infection.
The Journal of Allergy and Clinical Immunology, Apr 1, 2007
Atopic dermatitis (AD) is a chronic inflammatory skin disorder that is associated with recurrent ... more Atopic dermatitis (AD) is a chronic inflammatory skin disorder that is associated with recurrent bacterial and viral skin infections. 1 This has prompted the Center for Disease Control and Prevention (CDC) to exclude individuals with AD from smallpox vaccination with vaccinia virus (VV) due to the increased risk of developing eczema vaccinatum. Anti-microbial peptides (AMPs) are an integral component of the innate immune response due to their activity against invading pathogens. 2,3 Recent studies by our laboratory have demonstrated that two main families of AMPs-β-defensins and cathelicidins-are deficient in the skin of AD patients. 4,5 This deficiency may explain, in part, the increased propensity of AD patients to recurrent skin infections.
Although much data has been obtained related to the clinical manifestations of latex allergy and ... more Although much data has been obtained related to the clinical manifestations of latex allergy and the characterization of the protein allergens, little is known regarding the natural history of the disease. These studies were undertaken to demonstrate the immunological relevance of both dermal and respiratory exposure in the development of latex allergy and to investigate the role of co-exposure by these routes to other agents in the health care environment on the development of NRL sensitization. An initial study in female BALB/c mice demonstrated comparable rates of induction of latex specific IgE following dermal and respiratory latex exposure, demonstrating the importance of both routes in the development of latex allergy. Upon further investigation using whole body plethysmography, non-specific airway hyperreactivity to methacholine was observed in mice following both dermal and intratracheal sensitization with latex proteins. In contrast, at these exposure levels latex specific airway hyper-reactivity was only observed in dermally sensitized mice. Endotoxin, a common contaminant of powdered gloves, and glutaraldehyde, a frequently used cold sterilant, were chosen to investigate the immunomodulatory effects of other agents in the health care setting on the development of latex allergy. In comparison with mice exposed to latex alone, mice concurrently exposed to latex and increasing concentrations of endotoxin demonstrated ~50% lower levels of latex specific IgE and a decrease in latex specific airway hyper-reactivity and mucin production. The same animals demonstrated increased levels of latex specific IgG2a and IgA, cellular infiltration (i.e. macrophages and neutrophils) into the peribronchial and perivascular regions of the lung, messenger IFN-γ and IL-12 levels in the draining mediastinal lymph nodes, and non-specific airway hyper-reactivity upon respiratory challenge with methacholine. Upon concurrent dermal exposure to latex and concentrations of glutaraldehyde surrounding the permissible exposure limit, mice demonstrated a dose responsive increase in latex specific IgE levels through an as yet undetermined mechanism. These studies demonstrate the potential for mixed exposures in the health care environment to diversely modulate the development of IgE mediated responses to NRL proteins underscoring the importance of environmental factors in the development of allergies to foreign antigens. iii ACKNOWLEDGEMENTS To my advisor, mentor and friend, Dr. Barbara Jean Meade, for her knowledge, support, discipline, motivation and persistence in helping me grow as a scientist. To Dr. Albert E. Munson for always stimulating the mind to understand both the question and answer in all of science and life. To Drs. Christopher Cuff, Daniel Lewis, and Rosana Schafer for supporting me through out the course of my training and offering valuable insight into my research. To my predecessors, Drs. Michael Woolhiser, Scott Manetz, and Ben Hayes, for their direction, assistance, patience and advice during my early years in the laboratory. To friends along the way who have helped mold me both scientifically and personally throughout my stay in Morgantown. To Kurt Brumbaugh for his friendship, support through life experiences, and constant nagging about proper statistical analysis. To Melanie Flint (Crazy Brit) for both scientific stimulation and comic relief. To Kim Klink for scientific discussion, analysis of artificial precipitation, and humor. To Ashley Murray for being by my side, supporting me, and helping me maintain my sanity through the final stages of my dissertation and experiences ahead. To all of the staff at NIOSH who assisted me during the course of my education and research with special thanks to Leon Butterworth, Shahla Azadi, Beverly Fragale, Kim Collins, and the Pathology group. And most importantly, to my family, not only because they gave birth to me, but also because they have always told me to shoot for the stars and have supported me every step of the way.
The Journal of Allergy and Clinical Immunology, 2010
Background-Eczema vaccinatum (EV), a disseminated viral skin infection, is a life threatening com... more Background-Eczema vaccinatum (EV), a disseminated viral skin infection, is a life threatening complication of vaccinia virus (VV) inoculation in patients with atopic dermatitis (AD) and is thought to be associated with a defective innate immune response. However, the precise mechanism(s) and key factor(s) of EV are unknown. Objective-Given that patients with psoriasis, another inflammatory skin disorder, are not susceptible to EV, we compared the global transcriptional response of skin to VV in healthy, psoriatic, and AD individuals focusing on AD specific genes. We hypothesized that differences in the transcriptional response to VV between AD and psoriatic or healthy individuals would identify a defective pathway(s) that might be associated with the development of EV. Methods-Gene expression profiling of sham-treated and VV-treated unaffected skin explants from AD (n=12), psoriatic (n=12), or healthy (n=13) individuals were generated using U133_Plus2 (54613 probe sets) GeneChips and analyzed using GCOS_1.4/SAM_2.1/MAPPFinder_2.0 pipeline. Results-Sixty-seven genes were significantly affected by VV in AD, but not in psoriatic and healthy skin. Genes associated with defense response, response to wounding, and immune response were the most affected by VV in AD skin. All genes in these ontologies were downregulated including innate immunity genes LTB4R, ORM1, F2R, C9, and LBP. These findings were confirmed by real-time PCR and validated by PubMatrix analysis. ORM1, TLR4, and NLRP1 were also linked to AD severity. Conclusion-This study identified groups of innate immunity genes that are associated with the aberrant response of AD skin to VV and represent potential targets for EV pathogenesis.
Candida albicans (CA) infections have been associated with psoriasis onset or disease flares. How... more Candida albicans (CA) infections have been associated with psoriasis onset or disease flares. However, the integrated immune response against this fungus is still poorly characterized in psoriasis. We studied specific immunoglobulins in plasma and the CA response in cocultures of circulating memory CD45RA− cutaneous lymphocyte antigen (CLA)+/− T cell with autologous epidermal cells from plaque and guttate psoriasis patients (cohort 1, n = 52), and also healthy individuals (n = 17). A complete proteomic profile was also evaluated in plaque psoriasis patients (cohort 2, n = 114) regarding their anti-CA IgA levels. Increased anti-CA IgA and IgG levels are present in the plasma from plaque but not guttate psoriasis compared to healthy controls. CA cellular response is confined to CLA+ T cells and is primarily Th17. The levels of anti-CA IgA are directly associated with CLA+ Th17 response in plaque psoriasis. Proteomic analysis revealed distinct profiles in psoriasis patients with high a...
Objective Hidradenitis suppurativa (HS) is a chronic inflammatory disease with limited treatment ... more Objective Hidradenitis suppurativa (HS) is a chronic inflammatory disease with limited treatment options; therefore, the current study investigated the downstream signaling pathways that are differentially expressed in HS subjects and may drive disease pathogenesis. Methods The expression of 144 genes was evaluated in the skin of 16 healthy subjects and 34 subjects with mild to severe HS using QuantiGene Plex assay. Results One hundred and twenty-nine genes were significantly elevated in lesional HS skin as compared to the skin of healthy controls including pro-inflammatory cytokines (IL-1α, IL-6, TNF-α), IL-17-associated cytokines (IL-17A, IL-17F, IL-23A), the IL-10 family of cytokines (IL-10, IL-19, IL-20, IL-22, IL-24), and IFN family members (IFNA1, IFNB1, IFNG, IL-12B). This corresponded with increased expression of tyrosine kinases (JAK1, JAK3, BTK, SYK) and their downstream signaling partners (STAT1, STAT2, STAT3, STAT5A, STAT5B, STAT6). Conclusion These data illustrate the diverse immune activation in lesional HS skin and suggest that deeper interrogation of the disease heterogeneity may reveal unique opportunities for targeted therapies in designated subpopulations.
Background: Atopic dermatitis (AD) is a highly pruritic chronic inflammatory skin disorder. Ruxol... more Background: Atopic dermatitis (AD) is a highly pruritic chronic inflammatory skin disorder. Ruxolitinib, a selective inhibitor of Janus kinase 1 and Janus kinase 2, potently suppresses cytokine signaling involved in AD pathogenesis.
Autoimmune skin diseases are characterized by significant local and systemic inflammation that is... more Autoimmune skin diseases are characterized by significant local and systemic inflammation that is largely mediated by the Janus kinase (JAK)-signal transducer and activator of transcription (STAT) pathway. Advanced understanding of this pathway has led to the development of targeted inhibitors of Janus kinases (JAKinibs). As a class, JAK inhibitors effectively treat a multitude of hematologic and inflammatory diseases. Growing evidence suggests that JAK inhibitors are efficacious in atopic dermatitis, alopecia areata, psoriasis, and vitiligo. Additional evidence suggests that JAK inhibition might be broadly useful in dermatology, with early reports of efficacy in several other conditions. JAK inhibitors can be administered orally or used topically and represent a promising new class of medications. Here we review the evolving data on the role of the JAK-STAT pathway in inflammatory dermatoses and the potential therapeutic benefit of JAK-STAT antagonism.
Hidradenitis suppurativa (HS) is a chronic skin disease of the pilo-sebaceous apocrine unit chara... more Hidradenitis suppurativa (HS) is a chronic skin disease of the pilo-sebaceous apocrine unit characterized by significant inflammation and an impaired quality of life. The pathogenesis of HS remains unclear. To determine the HS skin and blood transcriptomes and HS blood proteome, patient data from previously published studies were analysed and integrated from a cohort of patients with moderate to severe HS (n = 17) compared to healthy volunteers (n = 10). The analysis utilized empirical Bayes methods to determine differentially expressed genes (DEGs) (fold change (FCH) >2.0 and false discovery rate (FDR) <0.05), and differentially expressed proteins (DEPs) (FCH>1.5, FDR<0.05). In the HS skin transcriptome (lesional skin compared to non-lesional skin), there was an abundance of immunoglobulins, antimicrobial peptides, and an interferon signature. Gene-sets related to Notch signalling and Interferon pathways were differentially activated in lesional compared to non-lesional...
Background: IL-13 has an important role in atopic dermatitis (AD) pathogenesis. Tralokinumab is a... more Background: IL-13 has an important role in atopic dermatitis (AD) pathogenesis. Tralokinumab is a fully human mAb that potently and specifically neutralizes IL-13. Objective: We sought to evaluate the efficacy and safety of tralokinumab in adults with moderate-to-severe AD. Methods: In this phase 2b study (NCT02347176), 204 adults were randomized 1:1:1:1 to receive 45, 150, or 300 mg of subcutaneous tralokinumab, or placebo, every 2 weeks for 12 weeks with concomitant topical glucocorticoids. Coprimary end points were change from baseline in Eczema Area Severity Index score and percentage of participants with an Investigator's Global Assessment response (0/1 score and reduction of > _2 grades from baseline) at week 12. Results: At week 12, 300 mg of tralokinumab significantly improved change from baseline in Eczema Area Severity Index score versus placebo (adjusted mean difference, 24.94; 95% CI, 28.76 to 21.13; P 5 .01), and a greater percentage of participants achieved an Investigator's Global Assessment response (26.7% vs 11.8%). Greater responses were found in participants with greater concentrations of biomarkers of increased IL-13 activity. Participants treated with 300 mg of tralokinumab demonstrated improvements in SCORAD, Dermatology Life Quality Index, and pruritus numeric rating scale (7-day mean) scores versus placebo. Upper respiratory tract infection was the most frequent treatment-emergent adverse event reported as related to study drug in the placebo (3.9%) and pooled tralokinumab (3.9%) groups. Conclusions: Tralokinumab treatment was associated with early and sustained improvements in AD symptoms and an acceptable safety and tolerability profile, thereby providing evidence for targeting IL-13 in patients with AD.
Clinical and experimental allergy : journal of the British Society for Allergy and Clinical Immunology, Jan 13, 2017
Atopic dermatitis (AD), psoriasis (PS), and contact dermatitis (CD) are common skin diseases, cha... more Atopic dermatitis (AD), psoriasis (PS), and contact dermatitis (CD) are common skin diseases, characterized by barrier disruption and systemic inflammation, with unique epidermal signatures and common inflammatory pathways identified by transcriptomic profiling. This study profiled proteomic signatures in serum from subjects with AD, PS, and CD compared with healthy controls (HC). Identify unique proteomic signatures to distinguish between inflammatory diseases with similar epidermal disruption and overlapping epithelial inflammation. Sera from 20 subjects with moderate to severe AD, 10 subjects with CD, 12 subjects with moderate to severe PS, 10 subjects with both AD and CD, and 10 HC with no history of skin disease was analyzed using high throughput proteomic analysis that detects expression of 1129 protein targets. Protein expression was compared between disease and HC, and across diseases for statistical significance (fold change ≥1.5 and false discovery rate ≤0.05), to identify...
International Archives of Allergy and Immunology, 2016
Atopic dermatitis (AD) is a chronic inflammatory skin disease that affects up to 25% of children ... more Atopic dermatitis (AD) is a chronic inflammatory skin disease that affects up to 25% of children and 10% of adults. The skin of patients with moderate to severe AD is characterized by significant barrier disruption and T helper 2 (Th2)-driven inflammation, which are thought to play a significant role in the pathogenesis of AD. Current management of AD is aimed at suppressing the inflammatory response and restoring the barrier function of the skin, reducing exacerbations, and preventing secondary skin infections. Combinations of treatment strategies are used to alleviate the symptoms of the disease; however, resolution is often temporary, and long-term usage of some of the medications for AD can be associated with significant side effects. Antibody therapies previously approved for other inflammatory diseases have been evaluated in patients with AD. Unfortunately, they have often failed to result in significant clinical improvement. Monoclonal antibodies and novel small molecules cur...
Proceedings of the National Academy of Sciences, 2009
Eczema vaccinatum (EV) is a complication of smallpox vaccination occurring in patients with atopi... more Eczema vaccinatum (EV) is a complication of smallpox vaccination occurring in patients with atopic dermatitis. In affected individuals, vaccinia virus (VV) spreads through the skin, resulting in large primary lesions and satellite lesions, and infects internal organs. BALB/c mice inoculated with VV at sites of Th2-biased allergic skin inflammation elicited by epicutaneous ovalbumin (OVA) sensitization exhibited larger primary lesions that were erosive, more satellite lesions, and higher viral loads in skin and internal organs than mice inoculated in saline-exposed skin, unsensitized skin, or skin sites with Th1-dominant inflammation. VV inoculation in OVA-sensitized skin induced marked local expression of IL-17 transcripts and massive neutrophil infiltration compared to VV inoculation in saline-exposed skin. Treatment with anti-IL-17 decreased the size of primary lesions, numbers of satellite lesions, and viral loads. Addition of IL-17 promoted VV replication in skin explants. These...
Recurrent skin infections in extrinsic atopic dermatitis (EAD) may be because of the suppression ... more Recurrent skin infections in extrinsic atopic dermatitis (EAD) may be because of the suppression of anti-microbial peptide (AMP) expression by interleukin (IL)-4 and IL-13. Twenty to thirty percent of AD, however, are classified as intrinsic atopic dermatitis (IAD). They exhibit normal serum IgE levels, no allergen-specific sensitization, and lower levels of IL-4 and IL-13 than EAD. Both forms of AD have increased propensity to skin infection, suggesting a novel mechanism for infection in IAD. In this study, we observed significantly decreased human b-defensin (HBD)-2 gene expression in the skin of both IAD (p ¼ 0.010) and EAD (p ¼ 0.004), as compared with psoriasis patients. Conversely, IAD (p ¼ 0.019) and EAD (p ¼ 0.002) skin lesions exhibited elevated IL-10 gene expression when compared with psoriasis. Using primary keratinocytes, we found that the deficiency in AMP expression is an acquired rather than a constitutive defect. Interestingly, neutralizing antibodies to IL-10 augmented the production of tumor necrosis factor-a and interferon-c by peripheral blood mononuclear cell from AD patients. Additionally, treatment of AD skin explants with anti-IL-10 augmented the expression of both HBD-2 and LL-37. Thus, increased levels of IL-10 may contribute to the AMP deficiency in both IAD and EAD by reducing cytokines that induce AMP.
Eczema vaccinatum is a potentially fatal, disseminated viral skin infection that develops in indi... more Eczema vaccinatum is a potentially fatal, disseminated viral skin infection that develops in individuals with atopic dermatitis after exposure to the vaccinia virus (VV). Despite advances in modern medicine, there are few options for those suffering from disseminated VV infections. Ceragenins (CSAs) are synthetic antimicrobial compounds designed to mimic the structure and function of endogenous antimicrobial peptides (AMPs). We show that CSA-13 exhibits potent antiviral activity against VV by (1) direct antiviral effects against VV; and (2) stimulating the expression of endogenous AMPs with known antiviral activity against VV. In addition, we show that a topical application of CSA-13 penetrates the skin and reduces subsequent satellite lesion formation. This suggests that treatment with CSA-13 may be an intervention for individuals with a disseminated VV skin infection.
Atopic dermatitis (AD) and psoriasis are the two most common chronic skin diseases. However patie... more Atopic dermatitis (AD) and psoriasis are the two most common chronic skin diseases. However patients with AD, but not psoriasis, suffer from frequent skin infections. To understand the molecular basis for this phenomenon, skin biopsies from AD and psoriasis patients were analyzed using GeneChip microarrays. The expression of innate immune response genes, human β defensin (HBD)-2, IL-8, and inducible NO synthetase (iNOS) was found to be decreased in AD, as compared with psoriasis, skin (HBD-2, p = 0.00021; IL-8, p = 0.044; iNOS, p = 0.016). Decreased expression of the novel antimicrobial peptide, HBD-3, was demonstrated at the mRNA level by real-time PCR (p = 0.0002) and at the protein level by immunohistochemistry (p = 0.0005). By real-time PCR, our data confirmed that AD, as compared with psoriasis, is associated with elevated skin production of Th2 cytokines and low levels of proinflammatory cytokines such as TNF-α, IFN-γ, and IL-1β. Because HBD-2, IL-8, and iNOS are known to be i...
Human β-defensins (HBDs) are a major class of antimicrobial peptides that play an important role ... more Human β-defensins (HBDs) are a major class of antimicrobial peptides that play an important role in the innate immune response, however, the induction and regulation of these antimicrobial peptides is not well understood. We demonstrate here that stimulation of keratinocytes with TNF-α/IFN-γ induces HBD-2 and HBD-3 by activating STAT-1 and NF-κB signaling. We further demonstrate that IL-4 and IL-13 activate STAT-6 and induce the suppressors of cytokine signaling (SOCS)-1 and -3. This interferes with STAT-1 and NF-κB signaling, thereby inhibiting TNF-α/IFN-γ-mediated induction of HBD-2 and HBD-3. These data suggest that targeting the STAT-1-signaling pathway or suppressor of cytokine signaling expression enhances β-defensin expression and represents a new therapeutic strategy for reduction of infection in human diseases associated with β-defensin deficiency.
Atopic dermatitis (AD) is an inflammatory skin disease associated with frequent skin infection an... more Atopic dermatitis (AD) is an inflammatory skin disease associated with frequent skin infection and impaired skin barrier function. Recent studies indicate that increased Th2 cytokine expression contributes to reduction in antimicrobial peptides and reduced filaggrin (FLG) expression, however, the mechanisms leading to this effect is unknown. Using proteomics, we found the S100 calcium-binding protein A11 (S100/A11) to be significantly downregulated in the presence of IL-4 and IL-13. Culturing keratinocytes with increased calcium concentrations significantly induced S100/A11 expression. This corresponded with an increase in human b-defensin (HBD)-3 and FLG expression. Interference of S100/A11 expression, by siRNA, inhibited induction of HBD-3 and FLG. Furthermore p21, a cyclin-dependent kinase inhibitor downstream of S100/A11, was required for calciummediated induction of HBD-3 and FLG. Importantly, transduction of p21-recombinant protein into keratinocytes prevented IL-4/IL-13-mediated inhibition of FLG and HBD-3 expression. S100/A11 and p21 gene expression was also found to be significantly lower in acute and chronic AD skin. This study demonstrates an important role for S100/A11 and p21 in regulating skin barrier integrity and the innate immune response.
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Papers by Michael Howell