Integrative genetic and genomic networks identify microRNA associated with COPD and ILD

Chronic obstructive pulmonary disease (COPD) and interstitial lung disease (ILD) are clinically and molecularly heterogeneous diseases. We utilized clustering and integrative network analyses to elucidate roles for microRNAs (miRNAs) and miRNA isoforms (isomiRs) in COPD and ILD pathogenesis. Short RNA sequencing was performed on 351 lung tissue samples of COPD (n = 145), ILD (n = 144) and controls (n = 64). Five distinct subclusters of samples were identified including 1 COPD-predominant cluster and 2 ILD-predominant clusters which associated with different clinical measurements of disease severity. Utilizing 262 samples with gene expression and SNP microarrays, we built disease-specific genetic and expression networks to predict key miRNA regulators of gene expression. Members of miR-449/34 family, known to promote airway differentiation by repressing the Notch pathway, were among the top connected miRNAs in both COPD and ILD networks. Genes associated with miR-449/34 members in the disease networks were enriched among genes that increase in expression with airway differentiation at an air-liquid interface. A highly expressed isomiR containing a novel seed sequence was identified at the miR-34c-5p locus. 47% of the anticorrelated predicted targets for this isomiR were distinct from the canonical seed sequence for miR-34c-5p. Overexpression of the canonical miR-34c-5p and the miR-34c-5p isomiR with an alternative seed sequence down-regulated NOTCH1 and NOTCH4. However, only overexpression of the isomiR down-regulated genes involved in Ras signaling such as CRKL and GRB2. Overall, these findings elucidate molecular heterogeneity inherent across COPD and ILD patients and further suggest roles for miR-34c in regulating disease-associated gene-expression.

Age of onset defines two distinct profiles of atopic dermatitis in adults

BACKGROUND

The incidence of adult-onset atopic dermatitis (AOAD) is increasing. However, the unique characteristics of AOAD compared to pediatric-onset AD persisting into adulthood (POAD) are underexplored, hampering the development of targeted-therapeutics for this growing population. We thus assessed the profile of AOAD in skin and blood compared to that of POAD.

METHODS

We collected skin biopsies and blood from adults with AOAD, POAD, and healthy controls (n = 15 in each group). Skin samples were analyzed by RNA sequencing, qRT-PCR, and immunohistochemistry, and Olink Proseek multiplex assay was used to identify the serum proteomic profile.

RESULTS

Compared to healthy controls, both AOAD and POAD showed cutaneous immune and barrier dysregulations with a shared Th2/Th22 hyperactivation. Overall, POAD showed greater inflammation in lesional skin, with more prominent expression of Th2/Th17/Th22 markers (CCL17/22, S100A8/9, IL-36A, PI3/Elafin, DEFB4) in POAD compared to AOAD (p-value < .05). In contrast, higher Th1-(IFN-γ, IL-2, IL-15, CCL5) upregulation and Th1-skewing were seen in AOAD. The epidermal barrier was also more compromised in POAD, with greater epidermal hyperplasia and lower expression of markers related to terminal differentiation, lipids, and cell adhesion. In parallel with increased rates of cardiovascular comorbidities, AOAD demonstrated many more significantly dysregulated proteins in serum (n = 148) compared to POAD (n = 86), including pro-inflammatory and cardiovascular-risk markers. Th1-related products showed significant correlations between their skin and blood expressions only in AOAD subjects.

CONCLUSION

Age-of-onset delineates two distinct endophenotypes in adult AD potentially suggesting the need for broader (beyond Th2) therapeutic targeting in AOAD.

Proteomic characterization of atopic dermatitis blood from infancy to adulthood

BACKGROUND

Patients with atopic dermatitis (AD) have systemic biomarker dysregulation that differs by age group; however, the proteomic characteristics of these age-based changes are unknown.

OBJECTIVE

To profile blood proteins of patients with AD across different age groups versus age-appropriate controls.

METHODS

Using the Olink high-throughput proteomic platform, we profiled 375 serum proteins of 20 infants (age, 0-5 years), 39 children (age, 6-11 years), 21 adolescents (age, 12-17 years), and 20 adults (age, ≥18 years) with moderate-to-severe AD and 83 age-appropriate controls.

RESULTS

Each group presented a distinct systemic proteomic signature. Th2-related proteins were increased in infant AD and further intensified with age through adolescence and adulthood (interleukin 4/CCL13/CCL17). In contrast, Th1 axis down-regulation was detected in infants with AD and gradually reversed to increased Th1 products (interferon γ/CXCL9/CXCL10/CCL2) in patients with AD from childhood to adulthood. Despite their short disease duration, infants already had evidence of systemic inflammation, with significant upregulation of innate immunity (interleukin 17C/ interleukin-1RN), T-cell activation/migration (CCL19), Th2 (CCL13/CCL17), and Th17 (PI3) proteins. Adults with AD present unique upregulation of cardiovascular proteins related to coagulation and diabetes.

LIMITATIONS

Cross-sectional observational study with a single time point.

CONCLUSION

Systemic immune signatures of AD are age-specific beyond the shared Th2 immune activation. These data advocate for precision medicine approaches based on age-specific AD profiles.

Crisaborole reverses dysregulation of the mild to moderate atopic dermatitis proteome towards nonlesional and normal skin

BACKGROUND

Safe and effective long-term topical treatments for atopic dermatitis (AD) remain limited.

OBJECTIVE

In this phase 2a, single-center, intrapatient, vehicle-controlled study, we examine the mechanism of action of crisaborole 2% ointment, a topical nonsteroidal PDE4 inhibitor, in a proteomic analysis of 40 adults with mild-to-moderate AD and 20 healthy subjects.

METHODS

Within the AD cohort, two target lesions were randomized in an intrapatient (1:1) manner to double-blind crisaborole/vehicle applied twice daily for 14 days. Punch biopsy specimens were collected for biomarker analysis at baseline from all participants, then from AD patients only at day 8 (optional) and day 15.

RESULTS

Compared to the vehicle, crisaborole significantly reversed dysregulation of the overall lesional proteome and of key markers and pathways (e.g. Th2, Th17/Th22, T-cell activation) associated with AD pathogenesis towards both nonlesional and normal skin. Significant clinical correlations were observed with markers associated with nociception and Th2, Th17, and neutrophilic activation.

LIMITATIONS

Study limitations include predominance of white patients in the cohort, relatively short treatment time, and regimented administration of crisaborole.

CONCLUSION

Our results demonstrate crisaborole-induced normalization of the AD proteome towards a non-lesional molecular phenotype and further support topical PDE4 inhibition in the treatment of mild-to-moderate AD.

Apremilast and narrowband ultraviolet B combination therapy suppresses Th17 axis and promotes melanogenesis in vitiligo skin: a randomized, split-body, pilot study in skin types IV-VI

Improved repigmentation of generalized vitiligo in skin types IV-VI has been reported in clinical response to combined therapy with apremilast and narrowband (NB)-UVB; however, tissue responses to combined therapy versus NB-UVB monotherapy have not been elucidated. We compared the change from baseline in cellular and molecular markers in vitiligo skin after combined therapy versus NB-UVB monotherapy. We assessed lesional and nonlesional skin samples from enrolled subjects and evaluated for immune infiltrates, inflammatory, and melanogenesis-related markers which were compared across different treatment groups. Combined therapy resulted in significant reduction of CD8⁺T cells and CD11c⁺ dendritic cells, downregulation of PDE4B and Th17-related markers, and upregulation of melanogenesis markers. This study was limited to small sample size, skin types IV-VI, and high dropout rate. Our molecular findings support the clinical analysis that apremilast may potentiate NB-UVB in repigmentation of generalized vitiligo in skin types IV-VI.

Secukinumab responses vary across the spectrum of congenital ichthyosis in adults

IMPORTANCE

Treatment of congenital ichthyoses primarily focuses on reversing skin scaling and is not pathogenesis based. Recent studies showed Th17 immune skewing, as in psoriasis, across the spectrum of ichthyosis, suggesting that targeting this pathway might broadly reduce disease severity.

OBJECTIVE

To determine whether secukinumab, an IL-17A inhibitor, can improve ichthyosis across several congenital ichthyosis subtypes.

DESIGN

Exploratory 16-week double-blind, randomized, placebo-controlled trial comparing secukinumab 300 mg every 4wks to placebo (1:1 randomization) in adults with the four major congenital ichthyosis subtypes (NCT03041038), followed by a 16-week open-label phase to evaluate response of the placebo-first group and a 20-week extension for safety. Significant differences in secukinumab- vs. placebo-treated subjects at Wk16 in the Ichthyosis Area Severity Index (IASI) score and lack of increased mucocutaneous bacterial and/or fungal infections were the co-primary efficacy and safety endpoints, respectively.

SETTING

Two tertiary referral centers: Northwestern University Feinberg School of Medicine, Chicago, and Mount Sinai Icahn School of Medicine, New York.

PARTICIPANTS

Twenty subjects ≥ 18 yo with genotype-confirmed epidermolytic ichthyosis, Netherton syndrome, lamellar ichthyosis, or congenital ichthyosiform erythroderma with at least moderate erythroderma.

RESULTS

IL-17A inhibition did not significantly reduce severity or increase mucocutaneous infections among the 18 who completed the 16-week double-blind phase. Five patients with 29-50% clinical improvement at Wk32 requested drug continuation. Th17-related biomarkers were not significantly reduced vs. baseline or placebo-treated levels.

LIMITATIONS

Small sample size; heterogeneous ichthyosis subsets.

CONCLUSION

IL-17 inhibition with secukinumab is safe, but not efficacious across the spectrum of adult ichthyoses.

CLINICALTRIALS

GOV REGISTRATION NUMBER

NCT03041038; first posted on 02/02/2017.

Delayed type hypersensitivity reactions to various allergens may differently model inflammatory skin diseases

BACKGROUND

Treatment of inflammatory skin diseases, including atopic dermatitis (AD) and psoriasis, is undergoing transformative changes, highlighting the need to develop experimental models of skin inflammation in humans to predict treatment responses.

METHODS

We topically or intradermally administered four common sensitizers (dust mite (DM), diphencyprone (DPCP), nickel (Ni), and purified protein derivative (PPD)) to the backs of 40 healthy patients and the skin hypersensitivity response was biopsied and evaluated using immunohistochemistry, RNA-seq, and RT-PCR.

RESULTS

All agents induced strong increases in cellular infiltrates (T-cells and dendritic cells) as compared to untreated skin (p < .05), with variable T helper polarization. Overall, DPCP induced the strongest immune responses across all pathways, including innate immunity (IL-1α, IL-8), Th1 (IFNγ, CXCL10), Th2 (IL-5, CCL11), and Th17 (CAMP/LL37) products, as well as the highest regulatory tone (FOXP3, IL-34, IL-37) (FDR <0.01). Nickel induced Th17 (IL-17A), Th1 (CXCL10) and Th2 (IL-4R) immune responses to a lesser extent than DPCP (p < .05). PPD induced predominantly Th1 (IFNγ, CXCL10, STAT1) and Th17 inflammation (IL-17A) (p < .05). DM induced modulation of Th2 (IL-13, CCL17, CCL18), Th22 (IL-22), and Th17/Th22 (S100A7/9/12) pathways (p < .05). Barrier defects that characterize both AD and psoriasis were best modeled by DPCP and Ni, followed by PPD, including downregulation of terminal differentiation (FLG, FLG2, LOR, LCEs), tight junction (CLDN1/CLDN8), and lipid metabolism (FA2H, FABP7)-related markers.

CONCLUSION

Our data imply that DPCP induced the strongest immune response across all pathways, and barrier defects characteristic of AD and psoriasis.

Scalp Biomarkers During Dupilumab Treatment Support Th2 Pathway Pathogenicity in Alopecia Areata

BACKGROUND

The mechanisms driving alopecia areata (AA) are still unclear, hindering development of targeted therapeutics. Specific Th2 targeting with dupilumab in AA provides a unique opportunity to dissect its pathogenesis and explore the role of Th2 pathway.

METHODS

We evaluated changes in scalp biomarkers in AA patients (with and without concomitant atopy) randomized to weekly dupilumab or placebo for 24 weeks, followed by open-label dupilumab for 24 weeks. Changes in biomarker levels were measured at weeks 12, 24, and 48, and were also correlated with clinical hair regrowth RESULTS: At week 24, preceding clinical hair regrowth outcomes, only dupilumab-treated patients presented significant suppression of cellular infiltrates, and multiple Th2-related, markers (CCL13/MCP-4, CCL18/PARC, CCL26/eotaxin-3, CCL24/Eotaxin-2), coupled with significant upregulation in the hair keratins. Th1-related suppression was evident later (week 48) when all patients received open-label dupilumab. Results were more pronounced in atopic AA patients, that showed 48% and 97% improvements in the lesional AA scalp profile at weeks 24 and 48, respectively, while 2% worsening was seen in the placebo arm at week 24. Moreover, placebo-treated patients presented 54% worsening in hair keratins as compared to baseline at week 24. At week 24, increases in hair keratins showed significant correlations only with decreases in Th2-related markers.

CONCLUSIONS

Scalp biomarkers provide evidence of dupilumab efficacy in AA, detected even prior to clinical response, with exclusive correlations between early suppression of Th2 markers and increased hair keratins. These findings strengthen previous reports suggesting a possible role for Th2 cytokines as AA drivers.

Analysis of alopecia areata surveys suggests a threshold for improved patient-reported outcomes

BACKGROUND

Although alopecia areata (AA) greatly impacts patients' quality of life (QoL), there is no adequate validation of AA-targeted QoL surveys in clinical trials, hindering sufficient representation of patient-reported outcomes.

OBJECTIVES

Better understanding of patient-reported outcomes may guide treatment goals and future clinical trials.

METHODS

In a recent randomized controlled trial testing dupilumab in AA, patients were administered the Alopecia Areata Quality of Life Index (AA-QLI) and the Alopecia Areata Symptom Impact Scale (AASIS) surveys, specifically evaluating QoL in patients with AA. An in-depth analysis was performed to assess the utility of these questionnaires in this patient population, both at baseline and after treatment, and to determine a threshold for improved patient-reported outcomes.

RESULTS

While AASIS correlated with baseline Severity of Alopecia Tool (SALT) scores and with therapeutic response, AA-QLI showed no correlation with AA severity before or after treatment. Itch strongly correlated with serum IgE levels across both surveys. Using various approaches to estimate a discriminative threshold for decreased impact of AA on QoL (by AASIS) following treatment, a SALT score of 20 points or less post-treatment was associated with improved patient-reported outcomes, including both AA-related symptoms and items within the daily activities/feelings domain such as 'feeling sad' and 'feeling anxious or worry'.

CONCLUSIONS

AASIS is better than AA-QLI to assess patient-reported outcomes. SALT ≤ 20 following treatment should be considered as a threshold for meaningful therapeutic outcome and as a clinical endpoint in future clinical trials for AA. What is already known about this topic? Alopecia areata greatly compromises quality of life, and affected patients have increased prevalences of depression, anxiety and social phobia. Despite the significant negative impact of the disease on patients' wellbeing, validation of targeted questionnaires in alopecia areata is lacking, and a therapeutic response threshold for improved patient-reported outcomes is unknown. What does this study add? This study investigated the utility of two different alopecia areata-targeted questionnaires - Alopecia Areata Quality of Life Index and Alopecia Areata Symptom Impact Scale (AASIS) - in a clinical trial setting. AASIS was found to correlate strongly with alopecia areata severity and clinical response. What are the clinical implications of this work? Patients with ≤ 20% scalp hair loss after treatment reported improvement in multiple quality-of-life items, suggesting this as a meaningful therapeutic outcome that may guide clinicians and improve the development of future clinical trials.

Transcriptomic Analysis of the Major Orphan Ichthyosis Subtypes Reveals Shared Immune and Barrier Signatures

Preliminary work suggested upregulation of inflammatory pathways in patients with common forms of ichthyosis. However, a comprehensive characterization of skin from various ichthyosis subtypes is unavailable, precluding the development of targeted treatments. Thus, we sought to characterize the immune and barrier profiles of common and subtype-specific skin transcriptomes in a large group of patients with ichthyosis. We performed a global RNA-sequencing analysis in 54 patients with ichthyosis (7 with Netherton syndrome, 13 with epidermolytic ichthyosis, 16 with lamellar ichthyosis, and 18 with congenital ichthyosiform erythroderma) and 40 healthy controls. Differentially expressed genes were defined on the basis of fold changes > 2 and false discovery rate < 0.05 criteria. We found robust and significant T helper (Th) 22/Th17 skewing in all subtypes (e.g., IL-17A/C/F, S100A7/8/9/12; P < 0.001) with modest changes in Th2 pathway, primarily in Netherton syndrome, and Th1 skewing in congenital ichthyosiform erythroderma. Across all subtypes (less evident in epidermolytic ichthyosis), lipid metabolism and barrier junction markers were downregulated (e.g., FA2H, CDH10/11/12/2; P < 0.05), whereas epidermal cornification and proliferation measures were upregulated (e.g., SPRR1A/1B/2C/2G, EREG; P < 0.05). Our findings suggest that the common ichthyosis variants share aberrations in Th17/Th22 and barrier function, with minimal Th2 modulation. This may help to elucidate the pathogeneses of these subtypes and inform the development of subtype-specific treatments.

Phase 2a randomized clinical trial of dupilumab (anti-IL-4Rα) for alopecia areata patients

BACKGROUND

Treatments for alopecia areata (AA) patients with extensive scalp hair loss are limited, and recent evidence supports a role for type 2 T-cell (Th2)-immune response in AA. Dupilumab, a monoclonal antibody inhibiting Th2 signaling, approved for type 2 diseases including atopic dermatitis, was evaluated in AA patients.

METHODS

Alopecia areata patients with and without concomitant atopic dermatitis were randomized 2:1 to receive weekly subcutaneous dupilumab (300 mg) or placebo for 24 weeks, followed by another 24-week dupilumab open-label phase. The primary outcome was change from baseline in the Severity of Alopecia Tool (SALT) score at week 24; secondary outcomes included a range of measures of hair regrowth.

RESULTS

Forty and 20 patients were assigned to the dupilumab and placebo arms, respectively. At week 24, disease worsening was documented in the placebo arm, with a least-squares mean change in the SALT score of -6.5 (95% confidence-interval [CI], -10.4 to -2.6), versus a change of 2.2 (95% CI, -0.6 to 4.94) in the dupilumab arm (p < .05). After 48 weeks of dupilumab treatment, 32.5%, 22.5% and 15% of patients achieved SALT₃₀ /SALT₅₀ /SALT₇₅ improvement, respectively, while in patients with baseline IgE ≥ 200 IU/ml response rates increased to 53.8%, 46.2%, and 38.5%, respectively. Moreover, baseline IgE predicts treatment response with 83% accuracy. No new safety signals were detected.

CONCLUSIONS

This hypothesis-driven trial is the first to indicate the possible pathogenic role of the Th2 axis and Th2 targeting in AA patients. Patient selection based on baseline serum IgE levels may improve treatment results (Clinicaltrials.gov number, NCT03359356).

Mapping atopic dermatitis and anti-IL-22 response signatures to type 2-low severe neutrophilic asthma

BACKGROUND

Transcriptomic changes in patients who respond clinically to biological therapies may identify responses in other tissues or diseases.

OBJECTIVE

We sought to determine whether a disease signature identified in atopic dermatitis (AD) is seen in adults with severe asthma and whether a transcriptomic signature for patients with AD who respond clinically to anti-IL-22 (fezakinumab [FZ]) is enriched in severe asthma.

METHODS

An AD disease signature was obtained from analysis of differentially expressed genes between AD lesional and nonlesional skin biopsies. Differentially expressed genes from lesional skin from therapeutic superresponders before and after 12 weeks of FZ treatment defined the FZ-response signature. Gene set variation analysis was used to produce enrichment scores of AD and FZ-response signatures in the Unbiased Biomarkers for the Prediction of Respiratory Disease Outcomes asthma cohort.

RESULTS

The AD disease signature (112 upregulated genes) encompassing inflammatory, T-cell, TH2, and TH17/TH22 pathways was enriched in the blood and sputum of patients with asthma with increasing severity. Patients with asthma with sputum neutrophilia and mixed granulocyte phenotypes were the most enriched (P < .05). The FZ-response signature (296 downregulated genes) was enriched in asthmatic blood (P < .05) and particularly in neutrophilic and mixed granulocytic sputum (P < .05). These data were confirmed in sputum of the Airway Disease Endotyping for Personalized Therapeutics cohort. IL-22 mRNA across tissues did not correlate with FZ-response enrichment scores, but this response signature correlated with TH22/IL-22 pathways.

CONCLUSIONS

The FZ-response signature in AD identifies severe neutrophilic asthmatic patients as potential responders to FZ therapy. This approach will help identify patients for future asthma clinical trials of drugs used successfully in other chronic diseases.

Th1, Th2 and Th17 inflammatory pathways predict cardiometabolic protein expression in serum of COVID-19 patients

A predominant source of complication in SARS-CoV-2 patients arises from a severe systemic inflammation that can lead to tissue damage and organ failure. The high inflammatory burden of this viral...

COVID-19 Symptoms Are Attenuated in Moderate-to-Severe Atopic Dermatitis Patients Treated with Dupilumab

Background

In the SARS-CoV-2/COVID-19 pandemic, we need to understand the impact of immunomodulatory medications on COVID-19 symptom severity in patients with inflammatory diseases, including the type 2/Th2 polarized skin disease, atopic dermatitis (AD).

Objective

Because it is believed that type 1/Th1 immunity controls viral infections and that there is a Th1/Th2 counter-regulation, we hypothesized that Th2 targeting with the IL-4Rα-antagonist, dupilumab, in patients with moderate-to-severe AD would rebalance the Th1/Th2 axis, potentially leading to attenuated COVID-19 symptoms.

Methods

A total of 1237 patients with moderate-to-severe AD in the Icahn School of Medicine at Mount Sinai Department of Dermatology were enrolled in a registry. Patients were screened for COVID-19-related symptoms and assigned a severity score (asymptomatic [0]-fatal [5]). Scores were compared among 3 treatment groups: dupilumab (n = 632), other systemic treatments (n = 107), and limited/no treatment (n = 498). Demographic and comorbid covariates were adjusted by multivariate generalized logistic regression models.

Results

The dupilumab-treated group showed reduced incidence and severity of COVID-19 symptoms versus other treatment groups. Dupilumab-treated patients were less likely to experience moderate-to-severe symptoms versus patients on other systemics (P = .01) and on limited/no treatment (P = .04), and less likely to experience any symptoms versus patients on other systemics (P = .01). This effect was seen in our entire cohort and in the subgroup of patients with verified COVID-19 or high-risk exposure.

Conclusions

Patients on dupilumab experienced less severe COVID-19 manifestations and lesser symptoms compared with patients on other systemics and on limited/no treatment. These results suggest that Th2 modulation with dupilumab may have a protective effect on anti-viral immune response in patients with AD.

Ritlecitinib and brepocitinib demonstrate significant improvement in scalp alopecia areata biomarkers

BACKGROUND

Janus kinase (JAK) inhibitors have shown encouraging results in the treatment of alopecia areata (AA), an autoimmune form of hair loss, in small, uncontrolled studies and case reports.

OBJECTIVE

We conducted a biopsy substudy during the randomized, double-blind, placebo-controlled first 24 weeks of a phase 2a clinical trial that evaluated the efficacy and safety of ritlecitinib, an inhibitor of JAK3 and the tyrosine kinase expressed in hepatocellular carcinoma (TEC) kinase family, and brepocitinib, an inhibitor of tyrosine kinase 2 (TYK2)/JAK1 in the treatment of AA.

METHODS

Change in biomarkers in lesional scalp biopsy samples between baseline and weeks 12 and 24 was an exploratory end point, and 46 patients participated from the ritlecitinib (n = 18), brepocitinib (n = 16), and placebo (n = 12) groups. Correlations of biomarkers with hair regrowth, measured using the Severity of Alopecia Tool (SALT) score, were also evaluated.

CLINICAL TRIAL REGISTRATION

NCT02974868.

RESULTS

At week 24, both ritlecitinib and brepocitinib demonstrated improvement exceeding 100% in the lesional scalp transcriptome toward a nonlesional profile. At week 12, the improvements in scalp tissue were greater with brepocitinib than ritlecitinib; however, at week 24, the improvements were greater with ritlecitinib.

CONCLUSIONS

For both ritlecitinib and brepocitinib, improvement in the SALT scores was positively associated with expression of T_H1 markers and negatively associated with expression of hair keratins. Larger, long-term clinical trials are warranted.

Vascular inflammation in moderate-to-severe atopic dermatitis is associated with enhanced Th2 response

BACKGROUND

In atopic dermatitis (AD), some studies have shown an association with increased cardiovascular disease in certain populations. However, other investigations found modest or no association. Despite conflicting results, molecular profiling studies in both AD skin and blood have demonstrated upregulation of atherosclerosis and cardiovascular risk-related markers. However, the underlying mechanisms connecting AD to vascular inflammation/atherosclerosis are unknown. In this study, we aim to determine factors associated with vascular inflammation/atherosclerosis in AD patients.

METHODS

We used 18-FDG PET-CT to characterize vascular inflammation in AD patients and healthy subjects. In parallel, we assessed their skin and blood immune profiles to determine AD-related immune biomarkers associated with vascular inflammation. We also assessed levels of circulating microparticles, which are known to be associated with increased cardiovascular risk.

RESULTS

We found significant correlations between vascular inflammation and Th2-related products in skin and blood of AD patients as well as atherosclerosis-related markers that were modulated by dupilumab. Circulating levels of endothelial microparticles were significantly higher in severe AD patients and tended to correlate with vascular inflammation assessed by PET-CT.

CONCLUSION

Vascular inflammation in AD is associated with enhanced Th2 response and clinical severity, which may explain cardiovascular comorbidities observed in select AD populations. Larger prospective studies are needed to further evaluate vascular inflammation and cardiovascular events and mortality in AD patients. Finally, as dupilumab treatment demonstrated significant modulation of atherosclerosis-related genes in AD patients compared to placebo, these data suggest that modulation of vascular inflammation with systemic treatment should be explored in patients with AD.

An integrated scalp and blood biomarker approach suggests the systemic nature of alopecia areata

BACKGROUND

Alopecia areata (AA) is characterized by immune dysregulation in both scalp and blood, but a large-scale approach establishing biomarkers of AA incorporating both scalp tissue and serum compartments is lacking. We aimed to characterize the transcriptomic signature of AA lesional and nonlesional scalp compared to healthy scalp and determine its relationship with the blood proteome in the same individuals, with comparative correlations to clinical AA disease severity.

METHODS

We evaluated lesional and nonlesional scalp tissues and serum from patients with moderate-to-severe AA (n = 18) and healthy individuals (n = 8). We assessed 33,118 genes in AA scalp tissue using RNAseq transcriptomic evaluation and 340 inflammatory proteins in serum using OLINK high-throughput proteomics. Univariate and multivariate approaches were used to correlate disease biomarkers with Severity of Alopecia Tool (SALT).

RESULTS

A total of 608 inflammatory genes were differentially expressed in lesional AA scalp (fold change/FCH>1.5, false discovery rate/FDR<0.05) including Th1 (IFNG/IL12B/CXCL11), Th2 (IL13/CCL18), and T-cell activation-related (ICOS) products. Th1/Th2-related markers were significantly correlated with AA clinical severity in lesional/nonlesional tissue, while keratins (KRT35/KRT83/KRT81) were significantly downregulated in lesional compared to healthy scalp (p < .05). Expression of cardiovascular/atherosclerosis-related markers (MMP9/CCL2/IL1RL1/IL33R/ST2/AGER) in lesional scalp correlated with their corresponding serum expression (p < .05). AA scalp demonstrated significantly greater biomarker dysregulation compared to blood. An integrated multivariate approach combining scalp and serum biomarkers improved correlations with disease severity/SALT.

CONCLUSION

This study contributes a unique understanding of the phenotype of moderate-to-severe AA with an integrated scalp and serum biomarker model suggesting the systemic nature of the disease, advocating for the need for immune-based systemic treatment.

High-dimensional analysis defines multicytokine T-cell subsets and supports a role for IL-21 in atopic dermatitis

BACKGROUND

Flow cytometry is a well-accepted approach for immune profiling; however, its value is restricted by the limited number of markers that can be analyzed simultaneously. Mass cytometry/CyTOF offers broad-scale immune characterization integrating large number of parameters. While partial blood phenotyping was reported in atopic dermatitis (AD), patients' comprehensive profiling, critical for leveraging new targeted treatments, is not available. IL-21 may be involved in inflammatory skin diseases but its role in AD is not well established.

METHODS

We studied T-cell polarization in the blood of 20 moderate-to-severe AD and 15 controls. Using CyTOF and an unsupervised analysis, we measured the frequencies and mean metal intensities of activated polar CD4⁺ /CD8⁺ T-cell subsets. Immunohistochemistry, immunofluorescence, and qRT-PCR were used to analyze skin samples.

RESULTS

Examining 24 surface, intracellular markers, and transcription factors, we identified six CD4⁺ and five CD8⁺ T-cell metaclusters. A CD4⁺ skin-homing IL-13⁺ monocytokine and a novel IL-13⁺ IL-21⁺ multicytokine metaclusters were increased in AD vs. controls (p < .01). While IL-13 signature characterized both clusters, levels were significantly higher in the IL-21⁺ group. Both clusters correlated with AD severity (r = 0.49, p = .029). Manual gating corroborated these results and identified additional multicytokine subsets in AD. Immunohistochemistry and immunofluorescence, validated by mRNA expression, displayed significantly increasedIL-21 counts and colocalization with IL-13/IL-4R in AD skin.

CONCLUSION

A multicytokine signature characterizes moderate-to-severe AD, possibly explaining partial therapeutic responses to one cytokine targeting, particularly in severe patients. Prominent IL-21 signature in blood and skin hints for a potential pathogenic role of IL-21 in AD.

Th2/Th1 Cytokine Imbalance Is Associated With Higher COVID-19 Risk Mortality

A major component of COVID-19 severe respiratory syndrome is the patient’s immune response to the SARS-CoV-2 virus and the consequential multi-organ inflammatory response. Several studies suggested a potential role of CD4⁺ T cells in COVID-19 severe respiratory syndrome. We first hypothesized that there is a type 2 helper (Th2)/type 1 helper (Th1) imbalance in older age, male, asthma, smokers, and high ACE2 expression phenotype in the airway of non-infected patients. Next, we hypothesized that a Th2/Th1 imbalance may predict higher mortality in COVID-19 infected hospitalized patients with and without patient reported current asthma. We first analyzed publicly available gene expression from the sputum of 118 moderate-to-severe asthma patients and 21 healthy controls, and from nasal epithelium of 26 healthy current smokers and 21 healthy never smokers. Secondly, we profiled 288 new serum proteomics samples measured at admission from patients hospitalized within the Mount Sinai Health System with positive SARS-CoV-2 infection. We first computed Th1 and Th2 pathway enrichment scores by gene set variation analysis and then compared the differences in Th2 and Th1 pathway scores between patients that died compared to those that survived, by linear regression. The level of Th2/Th1 imbalance, as determined by the enrichment score, was associated with age, sex, and ACE2 expression in sputum, and with active smoking status in nasal epithelium (p < 0.05). Th2/Th1 imbalance at hospital admission in sera of patients was not significantly associated with death from COVID-19 (p = 0.11), unless evaluated in the asthmatic strata (p = 0.01). Using a similar approach we also observed a higher Th17/Th1 cytokine imbalance in all deceased patients compared to those that survived (p < 0.001), as well as in the asthmatic strata only (p < 0.01). Th2/Th1 imbalance is higher in the sera of asthma patients at admission that do not survive COVID-19, suggesting that the Th2/Th1 interplay may affect patient outcomes in SARS-CoV2 infection. In addition, we report that Th17/Th1 imbalance is increased in all patients that die of COVID-19.

Scalp and serum profiling of frontal fibrosing alopecia reveals scalp immune and fibrosis dysregulation with no systemic involvement

BACKGROUND

Frontal fibrosing alopecia (FFA) is a progressive, scarring alopecia of the frontotemporal scalp that poses a substantial burden on quality of life. Large-scale global profiling of FFA is lacking, preventing the development of effective therapeutics.

OBJECTIVE

To characterize FFA compared to normal and alopecia areata using broad molecular profiling and to identify biomarkers linked to disease severity.

METHODS

This cross-sectional study assessed 33,118 genes in scalp using RNA sequencing and 350 proteins in serum using OLINK high-throughput proteomics. Disease biomarkers were also correlated with clinical severity and a fibrosis gene set.

RESULTS

Genes differentially expressed in lesional FFA included markers related to Th1 (IFNγ/CXCL9/CXCL10), T-cell activation (CD2/CD3/CCL19/ICOS), fibrosis (CXCR3/FGF14/FGF22/VIM/FN1), T-regulatory (FOXP3/TGFB1/TGFB3), and Janus kinase/JAK (JAK3/STAT1/STAT4) (Fold changes [FCH]>1.5, FDR<.05 for all). Only one protein, ADM, was differentially expressed in FFA serum compared to normal (FCH>1.3, FDR<.05). Significant correlations were found between scalp biomarkers (IL-36RN/IL-25) and FFA severity, as well as between JAK/STAT and fibrosis gene-sets (r>.6; P <.05).

LIMITATIONS

This study was limited by a small sample size and predominantly female FFA patients.

CONCLUSION

Our data characterize FFA as an inflammatory condition limited to scalp, involving Th1/JAK skewing, with associated fibrosis and elevated T-regulatory markers, suggesting the potential for disease reversibility with JAK/STAT inhibition.

Use of Tape Strips to Detect Immune and Barrier Abnormalities in the Skin of Children With Early-Onset Atopic Dermatitis

Importance

Molecular profiling of skin biopsies is the criterion standard for evaluating the cutaneous atopic dermatitis (AD) phenotype. However, skin biopsies are not always feasible in children. A reproducible minimally invasive approach that can track cutaneous disease in pediatric longitudinal studies or clinical trials is lacking.

Objective

To assess a minimally invasive approach using tape strips to identify skin biomarkers that may serve as a surrogate to biomarkers identified using whole-tissue biopsies.

Design, Setting, and Participants

This cross-sectional study of 51 children younger than 5 years recruited children with moderate to severe AD and children without AD from the dermatology outpatient clinics at a children's hospital. Sixteen tape strips were serially collected from the nonlesional and lesional skin of 21 children who had AD and were less than 6 months from disease initiation and from the normal skin of 30 children who did not have AD between January 22, 2016, and April 20, 2018.

Main Outcomes and Measures

Gene and protein expression were evaluated using quantitative real-time polymerase chain reaction and immunohistochemistry.

Results

A total of 51 children younger than 5 years were included in the study; 21 children had moderate to severe AD with less than 6 months of disease duration, and 30 children did not have AD. Of the 21 children with AD, the mean (SD) age was 1.7 (1.7) years, and most were male (15 [71.4%] and white (15 [71.4%]). Of the 30 children without AD, the mean (SD) age was 1.8 (2.0) years, and most were female (20 [66.7%]) and white (22 [73.3%]). Seventy-seven of 79 evaluated immune and barrier gene products were detected (gene detection rate, 97%) in 70 of 71 tape strips (sample detection rate, 99%), with 53 of 79 markers differentiating between children with lesional and/or nonlesional AD from children without AD. Many cellular markers of T cells (CD3), AD-related dendritic cells (Fc ε RI and OX40 ligand receptors), and key inflammatory (matrix metallopeptidase 12), innate (interleukin 8 [IL-8] and IL-6), helper T cell 2 (TH2; IL-4, IL-13, and chemokines CCL17 and CCL26), and TH17/TH22 (IL-19, IL-36G, and S100A proteins) genes were significantly increased in lesional and nonlesional AD compared with tape strips from normal skin. For example, IL-4 mean (SE) for lesional was -15.2 (0.91) and normal was -19.5 (0.48); P < .001. Parallel decreases occurred in epidermal barrier gene products (FLG, CLDN23, and FA2H) and negative immune regulators (IL-34 and IL-37). For example, the decrease for FLG lesional was mean (SE) -2.9 (0.42) and for normal was 2.2 (0.45); P < .001. Associations were found between disease severity or transepidermal water loss and TH2 (IL-33 and IL-4R) and TH17/TH22 (IL-36G and S100As) products in lesional and nonlesional AD skin (evaluated using the SCORing Atopic Dermatitis, Eczema Area and Severity Index, and Pruritus Atopic Dermatitis Quickscore tools).

Conclusions and Relevance

In this study, tape strips provide a minimally invasive alternative for serially evaluating AD-associated cutaneous biomarkers and may prove useful for tracking pediatric AD therapeutic response and predicting future course and comorbidities.

Immune and barrier characterization of atopic dermatitis skin phenotype in Tanzanian patients

BACKGROUND

Atopic dermatitis (AD) is a common disease, with particularly high prevalence found in Africa. It is increasingly recognized that patients with AD of different ethnic backgrounds have unique molecular signatures in the skin, potentially accounting for treatment response variations. Nevertheless, the skin profile of patients with AD from Africa is unknown, hindering development of new treatments targeted to this patient population.

OBJECTIVE

To characterize the skin profile of patients with AD from Africa.

METHODS

Gene expression studies, including RNA sequencing (using threshold of fold change of >2 and false discovery rate of <0.05) and real-time polymerase chain reaction, were performed on skin biopsies of Tanzanian patients with moderate-to-severe AD and controls.

RESULTS

Tanzanian AD skin presented robust up-regulations of multiple key mediators of both T helper 2 (T_H2) (interleukin 13 [IL-13], IL-10, IL-4R, CCL13,CCL17,CCL18,CCL26) and T_H22 (IL22, S100As) pathways. Markers related to T_H17 and IL-23 (IL-17A, IL-23A, IL-12, PI3, DEFB4B) and T_H1 (interferon gamma, CXCL9,CXCL10,CXCL11) were also significantly overexpressed in AD tissues (FDR<.05), albeit to a lesser extent. IL-36 isoforms revealed substantial up-regulations in African skin. The barrier fingerprint of Tanzanian AD revealed no suppression of hallmark epidermal barrier differentiation genes, such as filaggrin, loricrin, and periplakin, with robust attenuation of lipid metabolism genes (ie, AWAT1).

CONCLUSION

The skin phenotype of Tanzanian patients with AD is consistent with that of African Americans, exhibiting dominant T_H2 and T_H22 skewing, minimal dysregulation of terminal differentiation, and even broader attenuation of lipid metabolism-related products. These data highlight the unique characteristic of AD in Black individuals and the need to develop unique treatments targeting patients with AD from these underrepresented populations.

The molecular features of normal and atopic dermatitis skin in infants, children, adolescents, and adults

BACKGROUND

Although atopic dermatitis (AD) often presents in infancy and persists into adulthood, comparative characterization of AD skin among different pediatric age groups is lacking.

OBJECTIVE

We sought to define skin biopsy profiles of lesional and nonlesional AD across different age groups (0-5-year-old infants with disease duration <6 months, 6-11-year-old children, 12-17-year-old adolescents, ≥18-year-old adults) versus age-appropriate controls.

METHODS

We performed gene expression analyses by RNA-sequencing and real-time PCR (RT-PCR) and protein expression analysis using immunohistochemistry.

RESULTS

T_H2/T_H22 skewing, including IL-13, CCL17/thymus and activation-regulated chemokine, IL-22, and S100As, characterized the common AD signature, with a global pathway-level enrichment across all ages. Nevertheless, specific cytokines varied widely. For example, IL-33, IL-1RL1/IL-33R, and IL-9, often associated with early atopic sensitization, showed greatest upregulations in infants. T_H17 inflammation presented a 2-peak curve, with highest increases in infants (including IL-17A and IL-17F), followed by adults. T_H1 polarization was uniquely detected in adults, even when compared with adolescents, with significant upregulation in adults of IFN-γ and CXCL9/CXCL10/CXCL11. Although all AD age groups had barrier abnormalities, only adults had significant decreases in filaggrin expression. Despite the short duration of the disease, infant AD presented robust downregulations of multiple barrier-related genes in both lesional and nonlesional skin. Clinical severity scores significantly correlated with T_H2/T_H22-related markers in all pediatric age groups.

CONCLUSIONS

The shared signature of AD across ages is T_H2/T_H22-skewed, yet differential expression of specific T_H2/T_H22-related genes, other T_H pathways, and barrier-related genes portray heterogenetic, age-specific molecular fingerprints.

Tape strips from early-onset pediatric atopic dermatitis highlight disease abnormalities in nonlesional skin

BACKGROUND

Skin biopsies promote our understanding of atopic dermatitis/AD pathomechanisms in infants/toddlers with early-onset AD, but are not feasible in pediatric populations. Tape strips are an emerging, minimally invasive alternative, but global transcriptomic profiling in early pediatric AD is lacking. We aimed to provide global lesional and nonlesional skin profiles of infants/toddlers with recent-onset, moderate-to-severe AD using tape strips.

METHODS

Sixteen tape strips were collected for RNA-seq profiling from 19 infants/toddlers (<5 years old; lesional and nonlesional) with early-onset moderate-to-severe AD (≤6 months) and 17 healthy controls.

RESULTS

We identified 1829 differentially expressed genes/DEGs in lesional AD and 662 DEGs in nonlesional AD, vs healthy skin (fold-change ≥2, FDR <0.05), with 100% sample recovery. Both lesional and nonlesional skin showed significant dysregulations of Th2 (CCL17 and IL4R) and Th22/Th17 (IL36G, CCL20, and S100As)-related genes, largely lacking significant Th1-skewing. Significant down-regulation of terminal differentiation (FLG and FLG2), lipid synthesis/metabolism (ELOVL3 and FA2H), and tight junction (CLDN8) genes were primarily seen in lesional AD. Significant negative correlations were identified between Th2 measures and epidermal barrier gene-subsets and individual genes (FLG with IL-4R and CCL17; r < -0.4, P < .05). Significant correlations were also identified between clinical measures (body surface area/BSA, pruritus ADQ, and transepidermal water loss/TEWL) with immune and barrier mRNAs in lesional and/or nonlesional AD (FLG/FLG2 with TEWL; r < -0.4, P < .05).

CONCLUSION

RNA-seq profiling using tape strips in early-onset pediatric AD captures immune and barrier alterations in both lesional and nonlesional skin. Tape strips provide insight into disease pathomechanisms and cutaneous disease activity.

RNA Sequencing Keloid Transcriptome Associates Keloids With Th2, Th1, Th17/Th22, and JAK3-Skewing

Keloids are disfiguring, fibroproliferative growths and their pathogenesis remains unclear, inhibiting therapeutic development. Available treatment options have limited efficacy and harbor safety concerns. Thus, there is a great need to clarify keloid pathomechanisms that may lead to novel treatments. In this study, we aimed to elucidate the profile of lesional and non-lesional keloid skin compared to normal skin. We performed gene (RNAseq, qRT-PCR) and protein (immunohistochemistry) expression analyses on biopsy specimens obtained from lesional and non-lesional skin of African American (AA) keloid patients compared to healthy skin from AA controls. Fold-change≥2 and false-discovery rate (FDR)<0.05 was used to define significance. We found that lesional versus normal skin showed significant up-regulation of markers of T-cell activation/migration (ICOS, CCR7), Th2- (IL-4R, CCL11, TNFSF4/OX40L), Th1- (CXCL9/CXCL10/CXCL11), Th17/Th22- (CCL20, S100As) pathways, and JAK/STAT-signaling (JAK3) (false-discovery rate [FDR]<0.05). Non-lesional skin also exhibited similar trends. We observed increased cellular infiltrates in keloid tissues, including T-cells, dendritic cells, mast cells, as well as greater IL-4rα⁺, CCR9⁺, and periostin⁺ immunostaining. In sum, comprehensive molecular profiling demonstrated that both lesional and non-lesional skin show significant immune alternations, and particularly Th2 and JAK3 expression. This advocates for the investigation of novel treatments targeting the Th2 axis and/or JAK/STAT-signaling in keloid patients.

Arsenic and chromium levels in hair correlate with actinic keratosis/non-melanoma skin cancer: results of an observational controlled study

BACKGROUND

The role of heavy metals in carcinogenetic process has been widely established; however, information on the most common environmental metals that serve as major risk factors for actinic keratosis (AK)/non-melanoma skin cancer (NMSC) are still lacking. The aim of this study was to evaluate levels of the most common environmental heavy metals in hair of patients with AK/NMSC as compared to healthy controls.

METHODS

Thirty-one patients diagnosed with AK/NMSC and 34 healthy controls were enrolled. Patients were interviewed for heavy metals exposure and underwent hair analysis for detection of arsenic (As), cadmium (Cd), chromium (Cr), nickel (Ni) and lead (Pb). Continuous variables were analyzed using Wilcoxon Non-Parametric Rank Test and proportions were compared by Fisher's Exact Test. Statistical significance was determined by P<0.05.

RESULTS

In our cohort we observed 48.4% patients had AKs, 16.1% basal cell carcinoma (BCC), 9.7% squamous cell carcinoma (SCC) and 25.9% of patients presented with a combination of these lesions. There were significantly elevated levels of As and Cr in AK-NMSC group as compared to controls.

CONCLUSIONS

We identified a strong positive correlation between As and Cr concentration and AK/NMSC adding new clues to the scenery of NMSC risk factors that should be taken under consideration in exposed populations.

Arsenic and chromium levels in hair correlate with actinic keratosis/non melanoma skin cancer: results of an observational controlled study

BACKGROUND

The role of heavy metals in carcinogenetic process has been widely established however, information on the most common environmental metals that serve as major risk factors for actinic keratosis (AK)/non-melanoma skin cancer (NMSC) are still lacking. We aim to evaluate levels of the most common environmental heavy metals in hair of patients with AK/NMSC as compared to healthy controls.

METHODS

31 patients diagnosed with AK/NMSC and 34 healthy controls were enrolled. Patients were interviewed for heavy metals exposure and underwent hair analysis for detection of arsenic (As), cadmium (Cd), chromium (Cr), nickel (Ni) and lead (Pb). Continuous variables were analyzed using Wilcoxon non-parametric rank test and proportions were compared by Fisher exact test. Statistical significance was determined by p<0.05.

RESULTS

In our cohort we observed 48.4% patients had AKs, 16.1% basal cell carcinoma (BCC), 9.7% squamous cell carcinoma (SCC) and 25.9% of patients presented with a combination of these lesions. There were significantly elevated levels of As and Cr in AKNMSC group as compared to controls.

CONCLUSIONS

We identified a strong positive correlation between As and Cr concentration and AK/NMSC adding new clues to the scenery of NMSC risk factors that should be taken under consideration in exposed populations.

Abstract 5486: Time-dependent mathematical modeling of genetic alterations in acute myeloid leukemia

Acute myeloid leukemia (AML) is a complex, aggressive type of neoplasia characterized by mutations in myeloid stem cells. Here we perform a hierarchical and time-dependent classification of genomic and transcriptomic events that drive AML using data from The Cancer Genome Atlas.

The problem of mathematically modeling the interplay between somatic mutations, translocations, and gene expression changes during AML evolution is formulated as a mixed integer linear program. We define a connectivity index between driver genes and genes with expression changes that determines the assignment of abnormally expressed genes. Input data consists of a binary matrix with 46 columns (known driver genes) and a real-valued expression matrix with 210 columns (genes implicated in cancer development, chosen by overlapping the KEGG Pathways in Cancer set with our dataset). Gene expression data is preprocessed using Python v3.7.4 scripts so as to generate a binary matrix. The output of the model is a set of phases of cancer progression, each of which contains driver genes and genes with expression changes. The model was solved using CPLEX v12.6 with default parameters.

A total of 10 drivers, including DNMT3A, U2AF1, ASXL1 and translocations t(15;17) and t(8;21) were assigned to the initial phase of our model. This phase is characterized by point mutations in epigenetic modifier genes known to play a role in clonal hematopoiesis condition and pre-leukemic stages. The intermediate phase of our model comprised a total of 21 driver genes, including NPM1, RUNX1 and CEBPA, which are commonly used for AML risk stratification. The final phase contained a number of drivers typically associated with late stages of AML, such as FLT3 and TP53. Our three-phase model also revealed a gradual progression in gene expression changes. The majority of genes with altered expression, independently of the phase of progression, were linked to cell proliferation, the main affected pathways being PI3K/AKT activation and Wnt signaling. The initial phase included genes that code for transcription factors, cytoskeleton, GTPases, and cyclins, the majority of which are involved in cell proliferation and differentiation. The intermediate phase included genes involved in apoptosis, necroptosis, other specific pathways of myeloid differentiation, DNA damage repair and glucose homeostasis for energy metabolism. The final phase contained tumor suppressor genes, proto oncogenes activation, immune modulators and developmental genes.

Taken together, our results suggest that, at first, early epigenetic events lead to cell proliferation; then additional mutations impair myeloid differentiation, activate death mechanisms, DNA repair and metabolism processes, and further increase cellular capacity for proliferation; finally, new mutations in tumor suppressor genes establish malignant transformation, and immune pathways are modulated in AML cells.

Citation Format: Julia L. Fleck, Matheus O. Meirim, Ana B. Pavel, Luciana M. Gutiyama, Ilana R. Zalcberg. Time-dependent mathematical modeling of genetic alterations in acute myeloid leukemia [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 5486.

Tape-Strip Proteomic Profiling of Atopic Dermatitis on Dupilumab Identifies Minimally Invasive Biomarkers

Tape-stripping is a minimally invasive approach for skin sampling that captures the cutaneous immune/barrier abnormalities in atopic dermatitis (AD). However, tape-strips have not been used to evaluate molecular changes with therapeutic targeting. In this study, we sought to characterize the proteomic signature of tape-strips from AD patients, before and after dupilumab therapy. Twenty-six AD patients were treated with every-other-week dupilumab 300 mg for 16 weeks. Tape-strips from lesional and non-lesional skin were collected before and after treatment, and analyzed with the Olink proteomic assay. Using criteria of fold-change>1.5 and FDR < 0.05, 136 proteins significantly decreased after dupilumab treatment, corresponding to an overall mean improvement of 66.2% in the lesional vs. non-lesional AD proteome. Significant decreases after dupilumab were observed in immune markers related to general inflammation (MMP12), Th2 (CCL13/CCL17), Th17/Th22 (IL-12B, CXCL1, S100A12), and innate immunity (IL-6, IL-8, IL-17C), while the Th1 chemokines CXCL9/CXCL10 remained elevated. Proteins related to atherosclerosis/cardiovascular risk (e.g., SELE/E-selectin, IGFBP7, CHIT1/ chitotriosidase-1, AXL) also significantly decreased after treatment. Dupilumab therapy suppressed AD-related immune biomarkers and atherosclerosis/cardiovascular risk proteins. Tape-strip proteomics may be useful for monitoring therapeutic response in real-life settings, clinical trials, and longitudinal studies for AD and beyond.

A Preliminary 18F-FDG-PET/MRI Study Shows Increased Vascular Inflammation in Moderate-to-Severe Atopic Dermatitis

BACKGROUND

Recent data suggest that patients with atopic dermatitis (AD) have increased systemic immune activation and cardiovascular risk. However, unlike psoriasis, evaluation of active vascular inflammation using state-of-the-art imaging is lacking in AD.

OBJECTIVE

To assess aortic and carotid vascular inflammation using ¹⁸F-fluorodeoxyglucose-positron emission tomography/magnetic resonance imaging (¹⁸F-FDG-PET/MRI) imaging in moderate-to-severe AD versus healthy individuals.

METHODS

A total of 27 patients with moderate-to-severe AD and 12 healthy controls were imaged using ¹⁸F-FDG-PET/MRI. Target-to-background ratio (TBR) values were calculated in multiple segments of the aorta and carotid vessels.

RESULTS

Patients with AD had elevated aortic max TBR (fold change [FCH] = 1.45, P = .057) versus healthy controls and significantly elevated mean TBR (FCH = 1.20; P < .05) in the right carotid (RC) arteries versus controls. When examining greatest focal inflammation (most diseased segment [MDS] TBR), patients with AD had higher aortic inflammation (FCH = 1.28; P = .052). AD clinical severity significantly correlated with C-reactive protein (ρ = 0.60, P < .01) and with RC mean TBR levels (ρ = 0.60, P = .04). Stratifying patients into moderate-to-severe and very severe AD showed greater RC mean TBR in patients with very severe AD versus controls (FCH = 1.31; P = .02) and versus patients with moderate/severe AD (FCH = 1.23, P = .05). Aortic inflammation was also significantly greater in patients with very severe AD versus controls (max TBR: FCH = 1.6, P = .04; MDS TBR: FCH = 1.73, P = .03).

CONCLUSIONS

This preliminary study is the first that establishes greater vascular (aorta and carotid) inflammation in moderate-to-severe AD versus healthy controls. Furthermore, very severe AD showed higher inflammation than both moderate/severe patients and healthy controls. Future studies with larger patient cohorts and evaluation before and after treatment are needed to determine the extent to which vascular inflammation in AD is modifiable.

Frontal fibrosing alopecia shows robust T helper 1 and Janus kinase 3 skewing

BACKGROUND

Frontal fibrosing alopecia (FFA) is a scarring alopecia with unclear pathogenesis and a progressive course. The disease has a major impact on patients' quality of life and there is a lack of effective treatment to halt disease progression.

METHODS

We profiled lesional and nonlesional scalp biopsies collected in 2017 from patients with FFA (n = 12) compared with scalp biopsies from patients with alopecia areata (AA) (n = 8) and controls (n = 8) to evaluate gene and protein expression, including the primary outcome (CXCL9). We determined significant differences between biomarkers using a two-sided Student's t-test adjusting P-values by false discovery rate.

RESULTS

Significant increases were seen in CD8+ cytotoxic T cells, CD11c+ dendritic cells, CD103+ and CD69+ tissue-resident memory T cells in FFA and AA vs. control scalp (P < 0·05), with corresponding significantly upregulated granzyme B mRNA, particularly in FFA (P < 0·01). In AA, cellular infiltrates were primarily concentrated at the bulb, while in FFA these were mainly localized at the bulge. FFA demonstrated significant upregulation of T helper 1/intereferon (IFN) (IFN-γ, CXCL9/CXCL10), the Janus kinase/signal transducers and activators of transcription (JAK-STAT) pathway (STAT1, JAK3) and fibrosis-related products (vimentin, fibronectin; P < 0·05), with no concomitant downregulation of hair keratins and the T-regulatory marker, forkhead box P3, which were decreased in AA. The stem cell markers CD200 and K15 demonstrated significantly reduced expression only in FFA (P < 0·05).

CONCLUSIONS

These data suggest that follicular damage and loss of stem cells in FFA may be mediated through immune attack in the bulge region, with secondary fibrosis and reduced but still detectable stem cells. JAK/STAT-targeting treatments may be able to prevent permanent follicular destruction and fibrosis in early disease stages.

Cross-sectional study of blood biomarkers of patients with moderate to severe alopecia areata reveals systemic immune and cardiovascular biomarker dysregulation

BACKGROUND

Although there is increased understanding of the alopecia areata (AA) pathogenesis based on studies in scalp tissues, little is known about its systemic profile.

OBJECTIVE

To evaluate the blood proteomic signature of AA and determine biomarkers associated with increased disease severity.

METHODS

In a cross-sectional study, we assessed 350 inflammatory and cardiovascular proteins using OLINK high-throughput proteomics in patients with moderate to severe AA (n = 35), as compared with healthy individuals (n = 36), patients with moderate to severe psoriasis (n = 19), and those with atopic dermatitis (n = 49).

RESULTS

Seventy-four proteins were significantly differentially expressed between AA and control individuals (false discovery rate, <.05) including innate immunity (interleukin [IL] 6/IL-8), T helper (Th) type 1 (interferon [IFN] γ/CXCL9/CXCL10/CXCL11), Th2 (CCL13/CCL17/CCL7), Th17 (CCL20/PI3/S100A12), and cardiovascular-risk proteins (OLR1/OSM/MPO/PRTN3). Eighty-six biomarkers correlated with AA clinical severity (P < .05), including Th1/Th2, and cardiovascular/atherosclerosis-related proteins, including SELP/PGLYRP1/MPO/IL-18/OSM (P < .05). Patients with AA totalis/universalis showed the highest systemic inflammatory tone, including cardiovascular risk biomarkers, compared to control individuals and even to patients with atopic dermatitis and those with psoriasis. The AA profile showed some Th1/Th2 differences in the setting of concomitant atopy.

LIMITATIONS

Our analysis was limited to 350 proteins.

CONCLUSION

This study defined the abnormalities of moderate to severe AA and associated circulatory biomarkers. It shows that AA has systemic immune, cardiovascular, and atherosclerosis biomarker dysregulation, suggesting the need for systemic treatment approaches.

Kallikrein 7 Promotes Atopic Dermatitis-Associated Itch Independently of Skin Inflammation

Atopic dermatitis (AD) is a highly prevalent, itchy inflammatory skin disorder that is thought to arise from a combination of skin barrier defect and immune dysregulation. Kallikreins (KLK), a family of serine proteases with a diverse array of homeostatic functions, including skin desquamation and innate immunity, are hypothesized to contribute to AD pathogenesis. However, their precise role in AD has not been clearly defined. In this study, RNA sequencing analyses identified KLK7 as the most abundant and differentially expressed KLK in both human AD and murine AD-like skin. Further, in mice, Klk7 expression was localized to the epidermis in both steady state and inflammation. Unexpectedly, KLK7 was dispensable for the development of AD-associated skin inflammation. Instead, KLK7 was selectively required for AD-associated chronic itch. Even without the alleviation of skin inflammation, KLK7-deficient mice exhibited significantly attenuated scratching, compared with littermate controls, after AD-like disease induction. Collectively, our findings indicate that KLK7 promotes AD-associated itch independently from skin inflammation and reveal a previously unrecognized epidermal-neural mechanism of AD associated itch.