Elevation of serum-soluble E-selectin in atopic dermatitis

Proteomic, miRNA and bacterial biomarker patterns in atopic dermatitis patients and their course upon anti-IL-4Rα therapy

BACKGROUND

Identification of biomarkers is required for a systems medicine approach and personalized treatment in atopic dermatitis (AD). These biomarkers may not only aid in diagnosing but also might be suitable to predict the effectiveness of targeted treatment.

OBJECTIVE

We aimed to identify proteomic, microbial and miRNA biomarkers in AD patients and investigated their course in relation to the clinical response upon anti-IL-4Rα therapy.

METHODS

Proteomic and miRNA screening was performed in AD patients in comparison to healthy controls. Differentially regulated serum proteins, miRNA and selected skin microbiota were measured consecutively in 50 AD patients before and upon systemic dupilumab treatment. A random forest classifier was used to predict the outcome of dupilumab therapy based on the initial biomarker patterns.

RESULTS

We identified 27 proteomic candidates, miRNA and three microbial strains to be dysregulated in AD. CCL17, CCL13, CCL22, E-selectin and BDNF were differently regulated and significantly associated with treatment response. In contrast, neither the microbial composition nor the miRNA pattern was associated with treatment response upon dupilumab treatment.

CONCLUSION

AD patients display defined dysregulations regarding their systemic proteomic serum profile, miRNA patterns and their skin microbiome. The proteomic profile and selected skin bacteria changed profoundly upon anti-IL-4Rα therapy which was associated with an overall clinical response. This was not seen in miRNA-related biomarkers. Our findings support the hypothesis that biomarker profiles reflect treatment responses and may in the future be used to develop a personalized medicine approach for the treatment of AD patients.

Biomarkers in atopic dermatitis-a review on behalf of the International Eczema Council

Atopic dermatitis (AD) is a common yet complex skin disease, posing a therapeutic challenge with increasingly recognized different phenotypes among variable patient populations. Because therapeutic response may vary on the basis of heterogeneous clinical and molecular phenotypes, a shift toward precision medicine approaches may improve AD management. Herein, we will consider biomarkers as potential instruments in the toolbox of precision medicine in AD and will review the process of biomarker development and validation, the opinion of AD experts on the use of biomarkers, types of biomarkers, encompassing biomarkers that may improve AD diagnosis, biomarkers reflecting disease severity, and those potentially predicting AD development, concomitant atopic diseases, or therapeutic response, and current practice of biomarkers in AD. We found that chemokine C-C motif ligand 17/thymus and activation-regulated chemokine, a chemoattractant of TH2 cells, has currently the greatest evidence for robust correlation with AD clinical severity, at both baseline and during therapy, by using the recommendations, assessment, development, and evaluation approach. Although the potential of biomarkers in AD is yet to be fully elucidated, due to the complexity of the disease, a comprehensive approach taking into account both clinical and reliable, AD-specific biomarker evaluations would further facilitate AD research and improve patient management.

E-Selectin Ligands in the Human Mononuclear Phagocyte System: Implications for Infection, Inflammation, and Immunotherapy

The mononuclear phagocyte system comprises a network of circulating monocytes and dendritic cells (DCs), and “histiocytes” (tissue-resident macrophages and DCs) that are derived in part from blood-borne monocytes and DCs. The capacity of circulating monocytes and DCs to function as the body’s first-line defense against offending pathogens greatly depends on their ability to egress the bloodstream and infiltrate inflammatory sites. Extravasation involves a sequence of coordinated molecular events and is initiated by E-selectin-mediated deceleration of the circulating leukocytes onto microvascular endothelial cells of the target tissue. E-selectin is inducibly expressed by cytokines (tumor necrosis factor-α and IL-1β) on inflamed endothelium, and binds to sialofucosylated glycan determinants displayed on protein and lipid scaffolds of blood cells. Efficient extravasation of circulating monocytes and DCs to inflamed tissues is crucial in facilitating an effective immune response, but also fuels the immunopathology of several inflammatory disorders. Thus, insights into the structural and functional properties of the E-selectin ligands expressed by different monocyte and DC populations is key to understanding the biology of protective immunity and the pathobiology of several acute and chronic inflammatory diseases. This review will address the role of E-selectin in recruitment of human circulating monocytes and DCs to sites of tissue injury/inflammation, the structural biology of the E-selectin ligands expressed by these cells, and the molecular effectors that shape E-selectin ligand cell-specific display. In addition, therapeutic approaches targeting E-selectin receptor/ligand interactions, which can be used to boost host defense or, conversely, to dampen pathological inflammatory conditions, will also be discussed.

The role of selectins in alopecia areata

Introduction

One of the main histopathological features of alopecia areata (AA) is a lymphocytic infiltration that surrounds hair follicles. Soluble forms of E, L, P-selectins are known indicators of ongoing inflammation. There are no studies regarding the assessment of their contribution in AA.

Aim

To assess serum concentrations of selectins (E-selectin, L-selectin and P-selectin) in patients with AA in relation to selected clinical parameters, including disease severity and activity.

Material and methods

Sixty-four patients with AA were involved in the study. The diagnosis was based on physical examination and photodermoscopy. The control group consisted of 40 healthy subjects. The serum concentrations of soluble E-selectin, L-selectin and P-selectin were detected with ELISA method.

Results

Statistically significantly higher levels of E, P, L-selectins were found in AA patients as compared with the healthy group. Serum concentrations of soluble forms of E- and L-selectins correlated with the severity of the disease, while E-selectin with activity of AA.

Conclusions

This study shows that selectins may play an important role in the pathogenesis of AA and may be a target of future therapies in this disease.

The value of SCORAD and beyond. Towards a standardized evaluation of severity?

The clinical scoring systems of atopic dermatitis were analysed and compared. Some biological parameters that can correlate with the clinical score were also reviewed. After the definition of the disease based on validated clinical criteria, the second necessity was the availability of reliable severity scores to allow clinicians to verify the course of the disease and the efficacy of treatments. After many proposals, the SCORAD (SCORing Atopic Dermatitis), that required more than three years of work, was the first one that was validated. SCORAD is freely available from an internet site and can be easily calculated using dedicated software. EASI (Eczema Area and Severity Index) score has also been validated but it has been modified twice. Simpler systems include SASSAD (Six Area, Six Sign Atopic Dermatitis) and TIS score (Three-Item Severity score). In parallel, biological parameters were investigated. Eosinophil cationic protein, circulating basophils, major basic protein, soluble E-selectin, antistaphylococcal enterotoxin B, immunoglobulin E titres and macrophage-derived chemokine, can correlate significantly with the clinical score. The clinicians will not benefit directly from laboratory techniques and will employ clinical scores.

Nerve growth factor and substance P are useful plasma markers of disease activity in atopic dermatitis

BACKGROUND

Neurogenic components, such as neurotrophic factors and neuropeptides, are probably involved in the pathogenesis of atopic dermatitis (AD) via the neuroimmunocutaneous system. Numerous in vitro and in vivo studies have shown that nerve growth factor (NGF), the best-characterized member of the neurotrophin family, modulates the synthesis of the neuropeptide substance P (SP), both of which may be associated with the pathogenesis of human allergic diseases.

OBJECTIVES

To evaluate the levels of NGF and SP in the plasma of patients with AD and to examine their possible correlation with disease activity.

METHODS

We measured plasma levels of NGF by an immunoenzymatic assay and of SP by aradioimmunoassay in 52 patients with AD, and compared them with 35 normal non-atopic controls. The severity of the disease in AD patients was evaluated using validated clinical scoring systems.

RESULTS

Patients with AD had significant increases in plasma levels of NGF and SP compared with controls (P < 0.0005 and P < 0.0001, respectively). A positive correlation between the plasma levels of NGF and SP was found in AD patients (correlation coefficient, Cc = 0.920, P < 0.0001). There was a significant correlation of plasma NGF and SP levels with disease activity evaluated using three different scoring systems: the grading system of Rajka and Langeland (P < 0.001 and P < 0.01, respectively), the objective Severity Scoring of AD (Cc = 0.656, P < 0.005 and Cc = 0.752, P < 0.0005, respectively) and the Eczema Area and Severity Index (Cc = 0.740, P < 0.001 and Cc = 0.765, P < 0.005, respectively).

CONCLUSIONS

These data represent the first reported evidence of increased plasma levels of NGF and SP in an allergic human skin disease. They suggest that these neurogenic factors systemically modulate the allergic response in AD, probably through interactions with cells of the immune-inflammatory component. In addition, NGF and SP may be useful markers of disease activity in patients with AD.

Soluble E-selectin correlates with disease activity in cyclosporin A-treated patients with atopic dermatitis

BACKGROUND

The expression of adhesion molecules on endothelial cells regulates leukocyte migration. The level of soluble adhesion molecules which are shed into the circulation is known to reflect the degree of inflammation, and this level can therefore be used as an indicator of disease activity. The objective of this study was first to investigate the relationship between sE-selectin levels and disease activity parameters (scores of extent, severity, itch, and sleep) in atopic dermatitis (AD) patients, and second to determine the effect of therapy with an immunosuppressive drug (cyclosporin A) on sE-selectin levels.

METHODS

Fourteen patients with severe AD and 41 healthy controls were studied. sE-selectin was measured by ELISA both 2 weeks before therapy with cyclosporin A and after 16 weeks of treatment.

RESULTS

At baseline, the level of sE-selectin was significantly higher in patients with AD than in healthy control subjects (P<0.0001). After treatment of AD with cyclosporin A, there was a significant reduction of the sE-selectin levels (P<0.0001). In addition, changes in sE-selectin levels significantly correlated with changes in disease activity parameters such as severity (P<0.002) and extent of disease (P<0.049).

CONCLUSIONS

Soluble E-selectin is a new serologic marker in AD which reflects disease activity. Therefore, soluble E-selectin may be a useful parameter in the monitoring of this disease.

Soluble E-selectin serum levels correlate with disease activity in psoriatic patients

E-selectin is an adhesion molecule expressed on vascular endothelial cells in several inflammatory skin diseases, including psoriasis. It is responsible for the adherence between microvascular endothelium and neutrophils, monocytes, eosinophils and subsets of T cells. Soluble E-selectin (sE-selectin) serum levels were measured by ELISA in 32 psoriatic patients before treatment and compared with both post-treatment sE-selectin levels in 16 patients and sE-selectin values in 10 healthy individuals. Soluble E-selectin serum levels were significantly increased in psoriatic patients compared with healthy persons. Moreover, a significant correlation was demonstrated between sE-selectin values and PASI scores. No relationship was found between sE-selectin levels and duration of psoriasis. Soluble E-selectin serum levels decreased significantly after treatment of psoriasis. This phenomenon was more evident in patients with more severe psoriasis. In conclusion, sE-selectin serum levels correlate with the extent of psoriatic lesions and could be used as marker of the disease activity in psoriatic patients.

Elevated Soluble E-Selectin in Cutaneous Lupus Erythematosus

Elevated levels of soluble adhesion molecules (sCAMs); sE-Selectin, sICAM-1, and sVCAM-1 have been reported in various inflammatory and autoimmune diseases such as systemic lupus erythematosus (SLE), but not in cutaneous LE. 1.1.

PATIENTS AND METHODS

Sixty-nine serum samples from 51 LE patients, 24 with SLE, 19 with chronic cutaneous (DLE) and 8 with subacute cutaneous (SCLE) and sera from 32 controls were examined for sE-Selectin, sICAM-1 and sVCAM-1 using commercially available ELISA kits. Thirty serum samples from different time points were available from 12 LE patients. 1.2.

RESULTS

Significantly elevated levels of sE-Selectin were found in DLE patients with wide-spread lesions. In contrast, patients with SLE and SCLE did not have elevated levels of sE-Selectin but in concordance with earlier reports, sICAM-1 and sVCAM-1 were elevated in these patients. In serial samples it seemed that sE-Selectin correlated significantly with active cutaneous skin lesions while sICAM-1 remained elevated irrespective of disease activity. 1.3.

CONCLUSION

Since activated endothelial cells are the only source for sE-Selectin, our results suggest a more important role of endothelial cells in cutaneous LE than has previously been assumed. Further it might be speculated that selective inhibition of E-Selectin could have therapeutic implication in cutaneous LE.

Different patterns of soluble adhesion molecules in systemic and cutaneous lupus erythematosus

Circulating isoforms of cellular adhesion molecules (CAMs) have been described recently, and elevated levels of certain sCAMs have been reported in various inflammatory diseases such as systemic lupus erythematosus (SLE). There are previously no reports on sCAMs in cutaneous LE. Sera from 61 patients with LE: systemic (SLE: n=24), chronic cutaneous (discoid LE, DLE: n= 19) or subacute cutaneous (SCLE: n=8), chronic biologically false positive (CBFP) reactors for syphilis (n= 10) and 32 controls were examined for sICAM-1, sVCAM-1 and sE-Selectin with specific ELISA kits. Protocol forms were reviewed. We found significantly elevated levels of sE-Selectin in patients with DLE and widespread cutaneous symptoms, and a correlation between active cutaneous disease as well as polymorphous light eruption (PLE) and elevated levels of sE-Selectin. In contrast, patients with systemic LE did not have elevated levels of sE-Selectin, but in concordance with earlier reports, sICAM-1 and sVCAM-1 levels were elevated compared to controls in SLE, as well as in SCLE patients, which has not been reported previously. Since activated endothelial cells are the only source for E-Selectin, the elevated sE-Selectin level in patients with widespread and active cutaneous disease suggests a more important role for endothelial cells in the pathogenesis of cutaneous LE than previously assumed.

Evaluation of soluble cell adhesion molecules in atopic dermatitis

Recent studies have indicated the importance of cell adhesion molecules (CAMs) between the vascular endothelium and activated leukocytes in various inflammatory skin diseases. Soluble forms of CAMs (sCAMs) have also been detected in sera from such diseases. In order to elucidate the role of the soluble forms in skin inflammation, we determined the serum levels of E-selectin, vascular cell adhesion molecule-1 (VCAM-1), and intercellular adhesion molecule-1 (ICAM-1) in patients with atopic dermatitis (AD). Using an enzyme-linked immunosorbent assay, we quantified sCAMs levels in 21 patients with atopic dermatitis and in 16 healthy controls. In severe AD patients, levels of these three types of sCAMs were markedly elevated. sE-selectin was significantly elevated in severe AD over the levels in mild AD. A positive correlation with individual clinical activity was found for changes in the sE-selectin and sVCAM-1 levels. sE-selectin levels were correlated with the serum IgE levels and the number of eosinophils. The sVCAM-1 level was also significantly correlated with the number of monocytes. Among these three molecules, sE-selectin appeared to be the most sensitive clinical parameter in monitoring the clinical course of AD patients.

Soluble CD30 in pediatric patients with atopic dermatitis

Atopic dermatitis (AD) is a chronic, inflammatory skin disease in which a pathogenetic role of Th2 cells has been supposed. This study investigated the presence of soluble CD30 (sCD30), an activation marker of T-cell clones able to produce Th2-type cytokines, in sera from pediatric patients affected by AD (n = 25) with no symptoms of asthma or rhinitis. The severity of the disease was graded by both the SCORAD and Costa et al. clinical scoring systems. Serum levels of sCD30 were significantly higher in patients with AD in respect to both normal donors (n = 20) and urticaria patients (n = 10), and a positive correlation between serum sCD30 and clinical score was found (r = 0.508; P = 0.01) when AD patients were evaluated by Costa et al.'s method. Furthermore, a significant association (r = 0.443; P = 0.027) between sCD30 and serum levels of the soluble interleukin (IL)-2 receptor (sIL-2R) was observed in AD. The presence of high amounts of sCD30 in atopic patients seems to confirm the role of this molecule as an activation marker useful for in vivo evaluation of a Th2 immune response, and the correlation observed with both clinical score and sIL-2R levels indicates the role of sCD30 as an additional marker of disease activity in pediatric patients with AD.