T-helper 17 cytokines (interleukins 17, 21, 22, and 6, and tumor necrosis factor-α) in patients with alopecia areata: association with clinical type and severity

Inhibition of T-cell activity in alopecia areata: recent developments and new directions

Alopecia areata (AA) is an autoimmune disease that has a complex underlying immunopathogenesis characterized by nonscarring hair loss ranging from small bald patches to complete loss of scalp, face, and/or body hair. Although the etiopathogenesis of AA has not yet been fully characterized, immune privilege collapse at the hair follicle (HF) followed by T-cell receptor recognition of exposed HF autoantigens by autoreactive cytotoxic CD8+ T cells is now understood to play a central role. Few treatment options are available, with the Janus kinase (JAK) 1/2 inhibitor baricitinib (2022) and the selective JAK3/tyrosine kinase expressed in hepatocellular carcinoma (TEC) inhibitor ritlecitinib (2023) being the only US Food and Drug Administration-approved systemic medications thus far for severe AA. Several other treatments are used off-label with limited efficacy and/or suboptimal safety and tolerability. With an increased understanding of the T-cell-mediated autoimmune and inflammatory pathogenesis of AA, additional therapeutic pathways beyond JAK inhibition are currently under investigation for the development of AA therapies. This narrative review presents a detailed overview about the role of T cells and T-cell-signaling pathways in the pathogenesis of AA, with a focus on those pathways targeted by drugs in clinical development for the treatment of AA. A detailed summary of new drugs targeting these pathways with expert commentary on future directions for AA drug development and the importance of targeting multiple T-cell-signaling pathways is also provided in this review.

Alopecia Areata: Current Treatments and New Directions

Alopecia areata is an autoimmune hair loss disease that is non-scarring and is characterized by chronic inflammation at the hair follicle level. Clinically, patients' presentation varies from patchy, circumscribed scalp involvement to total body and scalp hair loss. Current management is guided by the degree of scalp and body involvement, with topical and intralesional steroid injections as primarily first-line for mild cases and broad immunosuppressants as the mainstay for more severe cases. Until recently, the limited number of blinded, randomized, placebo-controlled clinical trials for this disease had made establishing an evidence-based treatment paradigm challenging. However, growing insights into the pathogenesis of alopecia areata through blood and tissue analysis of human lesions have identified several promising targets for therapy. T-helper (Th) 1/interferon skewing has traditionally been described as the driver of disease; however, recent investigations suggest activation of additional immune mediators, including the Th2 pathway, interleukin (IL)-9, IL-23, and IL-32, as contributors to alopecia areata pathogenesis. The landscape of alopecia areata treatment has the potential to be transformed, as several novel targeted drugs are currently undergoing clinical trials. Given the recent US FDA approval of baricitinib and ritlecitinib, Janus kinase (JAK) inhibitors are a promising drug class for treating severe alopecia areata cases. This article will review the efficacy, safety, and tolerability of current treatments for alopecia areata, and will provide an overview of the emerging therapies that are leading the revolution in the management of this challenging disease.

Inheritance-Specific Dysregulation of Th1- and Th17-Associated Cytokines in Alopecia Areata

Autoimmune diseases tend to cluster in families, suggesting genetic predisposition to autoimmunity associated with familial background. We have previously reported similarities in gene expression patterns and PTPN22 polymorphisms between alopecia areata (AA) patients and their healthy relatives, but not unrelated healthy controls. However, the spectrum of disease promoting (or preventing) pathways that may be activated in blood relatives of AA patients remains to be defined. Here, we investigated the extent to which cytokines associated with the Th1 and Th17 pathway are differentially expressed in the blood of patients with AA and its clinical subtypes in comparison to both healthy relatives as well as unrelated healthy controls. A comprehensive set of Th1- and Th17-related cytokines were evaluated by ELISA. We found a significant elevation of the Th17 inducer IL-23, the Th17 product IL-17A, the Th1 hallmark cytokine IFNγ, and TNFα, a Th1 cytokine with relevance to the Th17 pathway in AA patients, regardless of disease subtype, compared to healthy individuals. On further examination, we found that healthy family members grouped together with patients in terms of elevated Th1- and Th17-pathway cytokines in an inheritance-specific manner, distinct from unrelated controls. The elevation of Th17-associated cytokines in healthy controls related to AA patients indicates that Th1 and Th17 dysregulation in AA may be genetically based. Of note, one unrelated control displayed elevated levels of IL-17A and IL-23 similar to those detected in patients. One year after initial blood draw, areas of beard hair loss consistent with the diagnosis of AA were reported by this individual, indicating that the elevation in Th17-related cytokines may have predictive value.

Biomarkers in alopecia Areata: A systematic review and meta-analysis

BACKGROUND

Alopecia areata (AA) is an autoimmune non-scarring alopecia that affects the scalp or any hair-bearing areas in the body. The pathophysiology of AA is complex, but Th1, Th2, and Th17 cytokines dysregulation, as well as chemokines, immunoglobulins and other biomarkers have been shown to play a role in the pathogenesis of the disease.

OBJECTIVE

To conduct a systematic review and Meta-analysis to identify biomarkers that reflect AA activity and severity that could be used to better assess disease activity and response in both trials and clinical practice.

METHODS

A literature search was conducted using the PUBMED, EMBASE and the Cumulative Index to Nursing and Allied Health Literature (CINAHL) from inception to December 2021. Articles reporting on associations between AA and serum clinical biomarkers (cytokines, chemokines, antibodies, immunoglobulins, and others) were included. Serum biomarkers were identified in patients with AA and were correlated with disease severity and patient characteristics (ex. age, sex, comorbidities). The quality of the studies was assessed using the National Heart, Lung, and Blood Institute's Quality Assessment Tool for Case-Control Studies. Meta-analysis pooling of the standardized mean differences (SMD) by the method of Cohen using the common-effect inverse-variance model was performed. For the Meta-analysis, data was pulled for all the markers with a minimum of 4 studies with means and standard deviations. Analysis of data reported as Median with range or inter-quartile range (IQR) revealed that the data was too skewed to recommend calculation and use of mean with standard deviation (SD). If the data were not skewed, mean and SD were calculated.

RESULTS

One thousand seven hundred fourteen studies were screened, with 91 included, reporting on a total of 52 biomarkers. Meta-analyses revealed pooled SMD that were significant for interleukin 6 (IL6), C-reactive protein (CRP) and vitamin D.

CONCLUSIONS

Serum IL6 and CRP levels are significantly increased in patients with AA compared to healthy age and sex matched controls. Conversely, serum vitamn D levels are significantly decreased in patients with AA compared to healthy age and sex matched controls. This data has the potenail to influence the clinical guidelines for the diagnostic workup of AA to include testing the serum levels of CRP and vitamin D.

MicroRNA-1246 Inhibits NFATc1 Phosphorylation and Regulates T Helper 17 Cell Activation in the Pathogenesis of Severe Alopecia Areata

BACKGROUND

We found microRNA (miR)-1246 to be significantly differentially expressed between severe active alopecia areata (AA) patients and healthy individuals.

OBJECTIVE

To explore the role and mechanism of miR-1246 in severe AA.

METHODS

Expression of miR-1246, dual-specific tyrosine phosphorylation-regulated kinase 1A (DYRK1A), and nuclear factor of activated T cells 1c (NFATc1) in peripheral CD4⁺ T cells and in scalp tissues of patients were detected using RT-qPCR, Western blot, and immunohistochemistry assays. Peripheral CD4⁺ T cells from the AA patients were transfected with lentiviral vectors overexpressing miR-1246. RT-qPCR and Western blot analysis were used to measure mRNA or protein expression of retinoic-acid-receptor-related orphan nuclear receptor gamma (ROR-γt), interleukin (IL)-17, DYRK1A, NFATc1, and phosphorylated NFATc1. Flow cytometry was used to assay the CD4⁺IL-17⁺ cells proportion. ELISA was used to measure cytokine levels.

RESULTS

miR-1246 levels decreased and DYRK1A and NFATc1 mRNA levels significantly increased in the peripheral CD4⁺ T cells and scalp tissues of severe active AA samples. NFATc1 protein expression was also significantly increased in the peripheral CD4⁺ T cells but not in the scalp tissues. NFATc1 positive cells were mainly distributed among infiltrating inflammatory cells around hair follicles. In peripheral CD4⁺ T cells of severe active AA, overexpression of miR-1246 resulted in significant downregulation of DYRK1A, NFATc1, ROR-γt, and IL-17 mRNA and phosphorylated NFATc1 protein, as well as a decrease in the CD4⁺IL-17⁺ cells proportion and the IL-17F level.

CONCLUSION

miR-1246 can inhibit NFAT signaling and Th17 cell activation, which may be beneficial in the severe AA treatment.

Interleukin-15 and Tumor Necrosis Factor-α in Iraqi Patients with Alopecia Areata

Background

Alopecia areata (AA) is a common form of noncicatricial hair loss of unknown cause, affecting 0.1-0.2% of the general population. Most evidence supports the hypothesis that it is disease of the hair follicle of autoimmune nature mediated by T-cells, with important cytokine role. Objective of the Study. The objective of this study is to study the association and changes in serum levels of interleukin-15 (IL-15) and tumor necrosis factor-α (TNF-α) in patients with AA in relation to the type, activity, and disease duration. Patients and Methods. Thirty-eight patients with AA and 22 individuals without the disease as controls were enrolled in this case-controlled study conducted in the Department of Dermatology in the Al-Kindy Teaching Hospital and Baghdad Medical City, Iraq, during a period from the 1st of April 2021 to the 1st of December 2021. Serum concentrations of IL-15 and TNF-α assessed using the enzyme-linked immunosorbent assay.

Results

The mean serum concentration values for IL-15 and TNF-α were higher significantly in patients with AA than in controls (2.35 versus 0.35 pg/mL and 50.11 versus 20.92 pg/mL, respectively). IL-15 and TNF-α showed no statistically significant differences in level in terms of the type, duration, and activity of the disease, but TNF-α significantly higher in those with totalis-type than in other types.

Conclusion

Both IL-15 and TNF-α are markers for alopecia areata. The level for these biomarkers was not affected by duration or disease activity, but it was affected by the type of disease, as the concentrations of IL-15 and TNF-α were higher in patient with Alopecia totalis than in other types of Alopecia.

Stratification of alopecia areata reveals involvement of CD4 T cell populations and altered faecal microbiota

Alopecia areata (AA) is an immune-mediated disease that causes non-scarring hair loss. Autoreactive CD8 T cells are key pathogenic effectors in the skin, and AA has been associated both with atopy and with perturbations in intestinal homeostasis. This study aimed to investigate mechanisms driving AA by characterizing the circulating immunophenotype and faecal microbiome, and by stratifying AA to understand how identified signatures associated with heterogeneous clinical features of the condition. Flow cytometric analyses identified alterations in circulating B cells and CD4 T cells, while 16S sequencing identified changes in alpha and beta diversity in the faecal microbiome in AA. The proportions of transitional and naïve B cells were found to be elevated in AA, particularly in AA samples from individuals with >50% hair loss and those with comorbid atopy, which is commonly associated with extensive hair loss. Although significant changes in circulating CD8 T cells were not observed, we found significant changes in CD4+ populations. In individuals with <50% hair loss higher frequencies of CCR6+CD4 ("Th17") and CCR6+CXCR3+CD4 ("Th1/17") T cells were found. While microbial species richness was not altered, AA was associated with reduced evenness and Shannon diversity of the intestinal microbiota, again particularly in those with <50% hair loss. We have identified novel immunological and microbial signatures in individuals with alopecia areata. Surprisingly, these are associated with lower levels of hair loss, and may therefore provide a rationale for improved targeting of molecular therapeutics.

Evaluation of the serum C-reactive protein-albumin ratio and its relationship with disease severity IN alopecia areata: A prospective case-control study

BACKGROUND

Alopecia areata (AA) is an autoimmune and inflammatory disease characterized by localized or diffuse non-scarring hair loss. The serum C-reactive protein (CRP)/albumin ratio (CAR) is a novel inflammatory marker and a significant prognostic indicator in several diseases.

AIM

We aimed to explore CAR in AA patients and healthy controls and analyze the possible correlation between CAR and disease severity.

METHOD

The present study was conducted with 65 eligible AA patients and 65 age- and gender-matched healthy controls. Disease severity was analyzed based on the Severity of Alopecia Tool (SALT) score. The CAR score was calculated by dividing serum CRP by the albumin content in both patient and healthy control groups.

FINDINGS

56.9% of the patients were male and 43.1% were female, and the mean age was 31.93 ± 9.67. The patient group' mean CAR level (0.42 ± 0.3) was statistically higher than that of the healthy controls (0.07 ± 0.04), (p < 0.05). There were positive correlations between disease severity, CAR (r = 0.65; p < 0.01), and CRP (r = 0.66; p < 0.01), while the correlation between disease severity and albumin was negative (r = -0.56; p < 0.01). In the receiver operating characteristic analysis conducted on disease severity, the area under the curve was 0.16 for albumin, 0.92 for CRP, and 0.95 for CAR. The optimum CAR for AA severity was 0.38 with 87% sensitivity and 92% specificity.

CONCLUSION

In the study, we determined that the CAR was higher in AA patients when compared to the control group, and the elevation was associated with disease severity. The present study findings demonstrated that alopecia areata was associated with systemic inflammation, and CAR is a useful inflammatory marker in AA patients.

Dupilumab-Associated Adverse Events During Treatment of Allergic Diseases

Among the new biological therapies for atopic diseases, dupilumab is a fully human monoclonal antibody directed against IL-4Rα, the common chain of interleukin-4 and interleukin-13 receptors. Dupilumab showed clinical improvements in patients with atopic dermatitis, asthma, and chronic rhinosinusitis and is currently under development for other indications. While dupilumab is considered to be well tolerated, a number of recent publications have reported various adverse events. This review aims to summarize the current knowledge about these adverse events, which may help clinicians to improve the follow-up of patients on dupilumab. Injection-site reactions are the most common reported adverse event. However, dupilumab has also been shown to cause ophthalmic complications (e.g., dry eyes, conjunctivitis, blepharitis, keratitis, and ocular pruritus), head and neck dermatitis, onset of psoriatic lesions, progression of cutaneous T-cell lymphoma exacerbation, alopecia areata, hypereosinophilia, and arthritis. Most are managed during dupilumab treatment continuation, but some (e.g., severe conjunctivitis) may result in a discontinuation of treatment. Their molecular origin is unclear and requires further investigations. Among other hypothesis, it has been suggested that T helper (Th)2-mediated pathway inhibition may worsen Th1/Th17-dependent immune responses. An ophthalmological examination for the presence of potential predictive indicators of ophthalmic adverse events is recommended before initiation of dupilumab therapy.

Immune-mediated alopecias and their mechanobiological aspects

Alopecia is a non-specific term for hair loss clinically diagnosed by the hair loss pattern and histological analysis of patient scalp biopsies. The immune-mediated alopecia subtypes, including alopecia areata, lichen planopilaris, frontal fibrosing alopecia, and central centrifugal cicatricial alopecia, are common, significant forms of alopecia subtypes. For example, alopecia areata is the most common autoimmune disease with a lifetime incidence of approximately 2% of the world's population. In this perspective, we discuss major results from studies of immune-mediated alopecia subtypes. These studies suggest the key event in disease onset as the collapse in immune privilege, which alters the hair follicle microenvironment, e.g., upregulation of major histocompatibility complex molecules and increase of cytokine production, and results in immune cell infiltration, inflammatory responses, and damage of hair follicles. We note that previous studies have established that the hair follicle has a complex mechanical microenvironment, which may regulate the function of not only tissue cells but also immune cell infiltrates. This suggests a potential for mechanobiology to contribute to alopecia research by adding new methods, new approaches, and new ways of thinking, which is missing in the existing literature. To fill this a gap in the alopecia research space, we develop a mechanobiological hypothesis that alterations in the hair follicle microenvironment, specifically in the mechanically responsive tissues and cells, partially due to loss of immune privilege, may be contributors to disease pathology. We further focus our discussion on the potential for applying mechanoimmunology to the study of T cell infiltrates in the hair follicle, as they are considered primary contributors to alopecia pathology. To establish the connection between the mechanoimmunological hypothesis and immune-mediated alopecia subtypes, we discuss what is known about the role of T cells in immune-mediated alopecia subtypes, using the most extensively studied AA as our model.

Sleep disturbance in alopecia areata: A cross-sectional study

Background

Alopecia areata (AA) is a nonscarring hair loss with autoimmune pathophysiology, which is associated with psychiatric disorders including anxiety and depression. Sleep disorders are commonly seen with anxiety and depression. Here we evaluate the sleep quality of AA patients.

Methods

This cross-sectional study involved 51 AA patients and 51 age- and sex-matched healthy controls. The sleep quality and day sleepiness were evaluated by the Pittsburgh Sleep Quality Index (PSQI) and Epworth Sleepiness Scale (ESS) questionnaires. The severity of AA was evaluated with the Severity of Alopecia Tool (SALT).

Results

Unlike the ESS score, the mean PSQI score was significantly higher in the AA group compared with the controls (7 ± 4.13 vs. 3.53 ± 1.96, p < 0.001). The number of cases with ESS ≥ 11, indicating the excess daytime sleepiness, was significantly higher in the AA group compared with controls (15 vs. 6, p = 0.02). There was no significant correlation between PSQI score and age, age of onset of the disease, or SALT score (p > 0.05). Anxiety and depression were more common in the AA group versus controls (p = 0.9). PSQI score was higher in AA patients who had anxiety and depression compared with those who did not (9.9 ± 5.28 vs. 4.76 ± 3.08, p = 0.001).

Conclusion

Sleep quality is impaired in AA patients. As expected, sleep would be more disturbed in AA cases with depression or anxiety. Therefore, attention to sleep quality and concomitant psychiatric diseases is essential in AA clinical management.

The current state of knowledge of the immune ecosystem in alopecia areata

Alopecia areata (AA) is an autoimmune disease that affects approximately 2% of the general population. Patients with AA most commonly present with one or more patches of hair loss on the scalp in defined circular areas. A fraction of patients progress to more severe forms of the disease, in some cases with involvement of all body surfaces. The healthy anagen stage hair follicle is considered an immune privileged site, described as an environment that suppresses inflammatory immune responses. However, in AA, this immune privileged state collapses and marks the hair follicle as a target for the immune system, resulting in peri- and intrafollicular infiltration by lymphocytes. The complexity of the inflammatory ecosystem of the immune response to the hair follicle, and the relationships between the cellular and soluble participants, in AA remains incompletely understood. Many studies have demonstrated the presence of various immune cells around diseased hair follicles; however, often little is known about their respective contributions to AA pathogenesis. Furthering our understanding of the mechanisms of disease in AA is essential for the novel identification of targeted therapeutics that are efficacious and have few unintended effects.

The Role of Serum Th1, Th2, and Th17 Cytokines in Patients with Alopecia Areata: Clinical Implications

Alopecia areata is a type of non-scarring hair loss. The dysregulation of numerous systemic Th1 (IL-2, IFN-γ, TNF, IL-12, and IL-18), Th2 (IL-4, IL-5, IL-6, IL-9, IL-10, IL-13, IL-17E, IL-31 and IL-33) and Th17 (IL-17, IL-17F, IL-21, IL-22, IL-23 and TGF-β) cytokines was observed in patients with alopecia areata. Positive correlations between the severity of alopecia areata and an increased serum level of various cytokines including IL-2, TNF, IL-12, IL-17, and IL-17E were reported in the literature. An increased serum level of numerous cytokines, such as IL-2, IL-6, TNF, IL-12, IL-17E, and IL-22, was described as positively correlated with the duration of the disease. Moreover, it was shown that increased pre-treatment serum level of IL-12 was a positive, while increased serum levels of IL-4 and IL-13 were negative prognostic markers for the efficacy of diphenylcyclopropenone. In conclusion, alopecia areata is associated with the dysregulation of systemic Th1, Th2 and Th17 cytokines with their role in the pathogenesis, clinical manifestations and prognosis of the disease. Available data indicate the most significant role of serum IL-2, TNF, IL-12, IL-17, and IL-17E as markers of disease activity. The serum levels IL-4, IL-12 and IL-13 may be useful as potential predictors of diphenylcyclopropenone efficacy.

Alopecia areata: Current understanding of the pathophysiology and update on therapeutic approaches, featuring the Japanese Dermatological Association guidelines

Alopecia areata (AA) is a relatively common nonscarring hairloss disease characterized by an autoimmune response to anagen hair follicles (HFs). Accumulated evidence suggests that collapse of the HF immune privilege subsequent to triggering events, represented by viral infection, leads to autoimmune response in which autoreactive cytotoxic CD8+NKG2D+ T cells mainly target exposed HF autoantigens. AA had been recognized as type 1 inflammatory disease, but recent investigations have suggested some roles of type 2- and Th17-associated mediators in AA pathogenesis. The significance of psychological stress in AA pathogenesis is less emphasized nowadays, but psychological comorbidities, such as depression and anxiety, attract greater interest in AA management. In this regard, the disease severity may not solely be evaluated by the extent of hair loss. Use of trichoscopy markedly improved the resolution of the diagnosis and evaluation of the phase of AA, which is indispensable for the optimization of treatment. For the standardization of AA management, the establishment of guidelines/expert consensus is pivotal. Indeed, the Japanese Dermatological Association (JDA) and other societies and expert groups have published guidelines/expert consensus reports, which mostly recommend intralesional/topical corticosteroid administration and contact immunotherapy as first-line treatments, depending on the age, disease severity, and activity of AA. The uniqueness of the JDA guidelines can be found in their descriptions of intravenous corticosteroid pulse therapy, antihistamines, and other miscellaneous domestically conducted treatments. Considering the relatively high incidence of spontaneous regression in mild AA and its intractability in severe subsets, the importance of course observation is also noted. Evidenced-based medicine for AA is currently limited, however, novel therapeutic approaches, represented by JAK inhibitors, are on their way for clinical application. In this review, the latest understanding of the etiopathogenesis and pathophysiology, and update on therapeutic approaches with future perspectives are summarized for AA, following the current version of the JDA AA management guidelines.

IFN-α and TNF-α serum levels and their association with disease severity in Egyptian children and adults with alopecia areata

BACKGROUND

Alopecia areata (AA) is an autoimmune skin disease characterized by abnormal levels of several cytokines, such as interferon alpha (IFN-α) and tumor necrosis factor-alpha (TNF-α), which are T-helper type 1 cytokines that have important roles in the pathogenesis of AA. The aim of our study was to correlate circulating IFN-α and TNF-α levels with disease severity, activity, and clinical type in patients with AA and to evaluate the relationship between the two cytokines.

METHODS

We investigated serum IFN-α and TNF-α levels in 72 patients with AA (35 children and 35 adults) and 75 healthy control individuals (34 children and 41 adults) using the enzyme-linked immunosorbent assay (ELISA) technique. We evaluated AA severity using the Severity of Alopecia Tool (SALT) and determined the activity based on dermoscopic criteria of disease activity.

RESULTS

Serum IFN-α and TNF-α concentrations were significantly higher in the patients than in the controls. There was a significant positive correlation between serum IFN-α and TNF-α levels in all patients with alopecia areata, as well as between serum TNF-α levels and disease severity in all patients and in children.

CONCLUSIONS

Our results support the association between IFN-α and TNF-α levels and AA and suggest that TNF-α might be related to disease severity.

Two Cases of Cutaneous Adverse Effects Induced by Tumor Necrosis Factor-Alpha Inhibitors

Here, we report two cases of cutaneous adverse effects possibly induced by the use of tumor necrosis factor-alpha (TNF-α) inhibitors. The first case presented alopecia areata (AA) and atopic dermatitis (AD) that developed during the treatment of ulcerative colitis using infliximab; the other case presented urticaria and AD that developed during the treatment of rheumatoid arthritis using etanercept. AA, AD, and urticaria are relatively common skin diseases; however, they are not well known as adverse effects of TNF-α inhibitors. Although immunological studies were not performed, the clinical courses suggested that these skin disorders might have developed as a result of an immune four-way imbalance in T helper 1 (Th1), Th2, Th17, and regulatory T cells by the administration of TNF-α inhibitors.

Pro- and anti-inflammatory response in neurological disorders associated to anti-glutamate decarboxylase antibodies

Rare conditions showing psychiatric symptoms and movement disorders have been linked with the presence of anti-glutamate decarboxylase antibodies. Proinflammatory and antiinflammatory immune responses were assessed in patients with neurological disorders associated to anti-glutamic acid decarboxylase antibodies (NDGAD). Immunoregulatory and proinflammatory cell populations were quantified by flow cytometry. No polarization toward Th1, Th2, or Th17 phenotypes was observed in NDGAD patients. Immunoregulatory responses were significantly reduced for Breg, activated Treg, Tr1, and Th3 cells, suggesting a deficient regulatory response, while intermediate monocyte levels were increased. The reduced levels of regulatory T and B cells suggest an impairment in regulatory immune response, while intermediate monocytes could be playing a role in the increased proinflammatory response.

Serum level of interleukin-15 in active alopecia areata patients and its relation to age, sex, and disease severity

Introduction

Autoimmune mechanisms with evident genetic background are the main components of alopecia areata (AA) pathogenesis. Interleukin 15 (IL-15) is considered as an important signalling cytokine. Its disordered expression has been linked to inflammatory autoimmune disorders.

Aim

The present study aimed to evaluate serum IL-15 in active AA patients and to assess its association with patients' sex, age, and disease severity.

Material and methods

IL-15 serum level was measured in 40 patients with active alopecia areata and 20 healthy controls using the ELISA technique. The severity of hair loss was assessed in accordance with the Severity of Alopecia Tool (SALT).

Results

A significantly higher serum level of IL-15 in AA patients than in controls was detected (p < 0.001). A significant positive correlation was detected between the SALT score and IL-15 serum level (r_s = 0.433, p = 0.005). No significant correlation between age of the patients and the serum level of IL-15 was observed (r_s = 0.224, p = 0.164). No significant difference in IL-15 serum level regarding patients' sex, history of disease recurrence, or family history of AA was noted.

Conclusions

The elevated serum level of IL-15 in active AA patients might reflect its role in disease pathogenesis as a key signalling cytokine. Its level is correlated with disease severity. However, IL-15 is not influenced by patients' gender or age.

Tumor necrosis factor (TNF)-α- 308 G/A gene polymorphism (rs1800629) in Egyptian patients with alopecia areata and vitiligo, a laboratory and in silico analysis

Purpose & methods

Several single-nucleotide polymorphisms (SNPs) in the promoter region of the TNF-α gene can cause variations in the gene regulatory sites and act as risk factors for some autoimmune disorders as alopecia areata (AA) and vitiligo. This study aimed to detect the serum TNF-α (sTNF) level (by ELISA) and the rs1800629 (by real-time PCR) among AA and vitiligo Egyptian patients and to determine their relation with disease duration and severity. In silico analysis of this SNP to study the molecular regulation of the mutant genotypes was also done.

Results

In AA patients, no risk was associated with the mutant genotypes vs. the normal genotype, or with A allele vs. G allele. The risk of vitiligo was significantly higher with the G/A and A/A genotypes compared with HCs (p = 0.011). Similarly, a significantly increased risk was noted in patients with A allele vs. G allele (p<0.0001). In AA and vitiligo patients, a significant increase in sTNF-α levels was noted in the mutant G/A genotypes vs. the normal G/G genotype (p<0.0001) and in the A allele vs the G allele (p<0.0001). According to the in silico analysis, this SNP could mainly affect the SP1 transcription factor binding site with subsequent effect on TNF-α expression.

Conclusion

According to results of the laboratory and the in silico study, the mutant TNF-α (308) genotypes were risk factors that conferred susceptibility to vitiligo among Egyptian patients but had no effect on the susceptibility to AA.

The Potential Role of Nutraceuticals as an Adjuvant in Breast Cancer Patients to Prevent Hair Loss Induced by Endocrine Therapy

Nutraceuticals, natural dietary and botanical supplements offering health benefits, provide a basis for complementary and alternative medicine (CAM). Use of CAM by healthy individuals and patients with medical conditions is rapidly increasing. For the majority of breast cancer patients, treatment plans involve 5–10 yrs of endocrine therapy, but hair loss/thinning is a common side effect. Many women consider this significant, severely impacting on quality of life, even leading to non-compliance of therapy. Therefore, nutraceuticals that stimulate/maintain hair growth can be proposed. Although nutraceuticals are often available without prescription and taken at the discretion of patients, physicians can be reluctant to recommend them, even as adjuvants, since potential interactions with endocrine therapy have not been fully elucidated. It is, therefore, important to understand the modus operandi of ingredients to be confident that their use will not interfere/interact with therapy. The aim is to improve clinical/healthcare outcomes by combining specific nutraceuticals with conventional care whilst avoiding detrimental interactions. This review presents the current understanding of nutraceuticals beneficial to hair wellness and outcomes concerning efficacy/safety in breast cancer patients. We will focus on describing endocrine therapy and the role of estrogens in cancer and hair growth before evaluating the effects of natural ingredients on breast cancer and hair growth.

The IL-23/IL-17 Pathway in Inflammatory Skin Diseases: From Bench to Bedside

Interleukin-17 (IL-17) is an essential proinflammatory cytokine, which is mainly secreted by the CD4⁺ helper T cells (Th17 cells) and subsets of innate lymphoid cells. IL-17A is associated with the pathogenesis of inflammatory diseases, including psoriasis, atopic dermatitis, hidradenitis suppurativa, alopecia areata, pityriasis rubra pilaris, pemphigus, and systemic sclerosis. Interleukin-23 (IL-23) plays a pivotal role in stimulating the production of IL-17 by activating the Th17 cells. The IL-23/IL-17 axis is an important pathway for targeted therapy for inflammatory diseases. Emerging evidence from clinical trials has shown that monoclonal antibodies against IL-23, IL-17, and tumor necrosis factor are effective in the treatment of patients with psoriasis, atopic dermatitis, hidradenitis suppurativa, pityriasis rubra pilaris, pemphigus, and systemic sclerosis. Here, we summarize the latest knowledge about the biology, signaling, and pathophysiological functions of the IL-23/IL-17 axis in inflammatory skin diseases. The currently available biologics targeting the axis is also discussed.

Increased Serum Level and High Tissue Immunoexpression of Interleukin 17 in Cutaneous Lichen Planus: A Novel Therapeutic Target for Recalcitrant Cases?

Background

Interleukin-17 is supposed to play an important role in the pathogenesis of oral lichen planus (OLP). However, there is scarce data in the literature on its significance in the cutaneous variant of the disease.

Objectives

To determine the serum level and tissue immunoexpression of IL-17 in cutaneous lichen planus (CLP).

Methods

Fifty-two adult patients with CLP, without any significant autoimmune or inflammatory conditions, were included in the first part of the study. The control group consisted of 27 age- and sex-matched healthy volunteers. Serum concentration of IL-17 was quantified using enzyme-linked immunosorbent assay (ELISA) kit. In the second part of the study, the tissue expression of IL-17 was assessed in archival paraffin-embedded biopsy specimens from CLP (n = 14) against normal control tissues (n = 11) using immunohistochemical assays. The expression was evaluated using Zeiss Axio Imager A2 light microscope. Positively stained cells were counted in 10 fields of view for biopsy specimen at 200x magnification, and the mean value was calculated.

Results

The serum level of IL-17 was significantly elevated in patients with CLP, compared with healthy volunteers (0.218 ± 0.221 ng/ml versus 0.126 ± 0.058 ng/ml, respectively; p = 0.025). No correlation was found between the serum concentration of IL-17 and patient age, gender, disease duration, extent of skin involvement, the presence or intensity of pruritus, and coexistence of mucosal lesions. In tissue samples from CLP lesions, significantly higher numbers of cells expressing IL-17 were found when compared to a healthy skin (p < 0.001).

Conclusion

Elevated serum concentration of IL-17 and high expression in a lesional skin support the hypothesis that IL-17 is implicated in the immunopathogenesis of CLP. These findings may constitute a premise for the future use of anti-IL-17 monoclonal antibodies in the treatment of severe and recalcitrant forms of CLP.

Bidirectional association between alopecia areata and sleep disorders: a population-based cohort study in Taiwan

BACKGROUND

The relationship between alopecia areata (AA) and sleep disorders remains uncertain. This study aims to investigate the bidirectional association between AA and sleep disorders.

METHODS

To assess the risk of developing sleep disorders, we recruited 5648 patients with AA and 22,592 matched controls from the National Health Insurance Research Database (NHIRD) in Taiwan. Similarly, risk of developing AA was assessed in 93,130 patients with sleep disorders (including 7310 patients with obstructive sleep apnea [OSA] and 85,820 patients with non-apnea insomnia) and 372,520 matched controls. Cox regression model was used for the analysis.

RESULTS

AA patients had a significantly increased risk of developing OSA (adjusted hazard ratio [aHR] 3.80; 95% confidence interval [CI] 2.53-5.71) and non-apnea insomnia (aHR 4.20; 95% CI 3.68-4.79). Conversely, presence of sleep disorders significantly increased the risk of AA development (aHR 4.70; 95% CI 3.99-5.54). Both OSA (aHR 3.89; 95% CI 2.46-6.16) and nonapnea insomnia (aHR 4.77; 95% CI 4.03-5.64) were associated an increased risk of developing AA.

CONCLUSIONS

Patients with AA have a higher risk of developing sleep disorders compared to controls, and vice versa. Further studies are needed to investigate the shared pathogenic mechanism underlying these two conditions.

Bidirectional association between alopecia areata and major depressive disorder among probands and unaffected siblings: A nationwide population-based study

BACKGROUND

Alopecia areata (AA) has long been associated with major depressive disorder (MDD). However, most evidence to date has derived from cross-sectional or case-control studies.

OBJECTIVE

To investigate the bidirectional association between AA and MDD among probands and unaffected siblings.

METHODS

Study participants were recruited from the National Health Insurance Research Database in Taiwan. We included 2123 probands with AA, 2298 unaffected siblings, and 9192 matched controls to assess the risk of MDD. We included 16,543 probands with MDD, 17,352 unaffected siblings, and 69,408 matched controls to assess the risk of AA. The Breslow-Cox model was used to calculate the adjusted relative risk.

RESULTS

Compared with controls, AA probands and unaffected siblings had adjusted relative risks of 8.22 (95% confidence interval [CI], 6.41-10.54) and 2.55 (95% CI, 1.91-3.40), respectively, for MDD. MDD probands and unaffected siblings had adjusted relative risks for AA of 1.66 (95% CI, 1.24-2.22) and 1.64 (95% CI, 1.27-2.12), respectively.

LIMITATION

The National Health Insurance Research Database lacked information on disease severity, body mass index, smoking habit, alcohol consumption, and stressful life events.

CONCLUSION

Our study demonstrated a bidirectional association between AA and MDD among probands and unaffected siblings, thus suggesting shared familial mechanisms underlying AA and MDD.

Regulatory impairment in untreated Parkinson's disease is not restricted to Tregs: other regulatory populations are also involved

BACKGROUND

Parkinson's disease (PD) is the second most common neurodegenerative disease in the world. Various studies have suggested that the immune response plays a key role in this pathology. While a predominantly pro-inflammatory peripheral immune response has been reported in treated and untreated PD patients, the study of the role of the regulatory immune response has been restricted to regulatory T cells. Other immune suppressive populations have been described recently, but their role in PD is still unknown. This study was designed to analyze the pro and anti-inflammatory immune response in untreated PD patients, with emphasis on the regulatory response.

METHODS

Thirty-two PD untreated patients and 20 healthy individuals were included in this study. Peripheral regulatory cells (CD4+Tregs, Bregs, CD8+Tregs, and tolerogenic dendritic cells), pro-inflammatory cells (Th1, Th2, and Th17 cells; active dendritic cells), and classical, intermediate, and non-classical monocytes were characterized by flow cytometry. Plasmatic levels of TNF-α, IFN-γ, IL-6, GM-CSF, IL-12p70, IL-4, IL-13, IL-17α, IL-1β, IL-10, TGF-β, and IL-35 were determined by ELISA.

RESULTS

Decreased levels of suppressor Tregs, active Tregs, Tr1 cells, IL-10-producer CD8regs, and tolerogenic PD-L1+ dendritic cells were observed. With respect to the pro-inflammatory response, a decrease in IL-17-α and an increase in IL-13 levels were observed.

CONCLUSION

A decrease in the levels of regulatory cell subpopulations in untreated PD patients is reported for the first time in this work. These results suggest that PD patients may exhibit a deficient suppression of the pro-inflammatory response, which could contribute to the pathophysiology of the disease.

Medicated thread moxibustion for alopecia areata: A case report

RATIONALE

According to the literature reports and clinical studies on alopecia areata (AA) from 2008 to 2018, most clinical treatments have been oral drugs and external ointments. At present, systemic immunosuppressive therapy has been widely used in AA, but there are various side effects such as elevated liver enzymes, gastrointestinal discomfort, poor drug compliance, and repeated illness. We present a case report describing a traditional medicine treatment for AA that uses an ethnic therapy of Zhuang medicine, a kind of Traditional Chinese Medicine, namely, medicated thread moxibustion.

PATIENT CONCERNS

A 36-year-old man endured AA after going through a family misfortune. Half a year ago, his father passed away suddenly. Since then, he suffered continuous anguish, alcoholism and hair loss, especially in the past 2 months. A coin-shaped area of hair loss began to appear at the top of his head and gradually expanded to the surrounding region.

DIAGNOSES

A diagnosis of AA was made in the dermatology department of a local hospital.

INTERVENTIONS

The patient was treated with the medicated thread moxibustion method of Traditional Zhuang Medicine at the Kuihua (special points of Zhuang medicine), Zusanli (ST 36), Xuehai (SP 10), Baihui (DU 20), and Taichong (LR 3) points every other day for 4 weeks.

OUTCOMES

The area of hair loss showed slight improvement after 1 week of treatment. Only just a sprinkling of wooly hairs, whose color and thickness were similar to those of fine facial hairs, began to emerge sporadically from the follicles; they could be seen only in a bright light. When the patient saw the obvious curative effect, we continued the treatment for 2 weeks with the patient's consent. Three weeks later, the patchy AA area was covered with small cotton-like hairs of different lengths and uneven colors.

LESSONS

The medicated thread moxibustion method of Zhuang medicine can be an effective alternative treatment in patients with AA.

IL-17 and its role in inflammatory, autoimmune, and oncological skin diseases: state of art

Recent data support the theory of the involvement of IL‐17 in the pathogenesis of several chronic inflammatory skin diseases (psoriasis, atopic dermatitis, acne, hidradenitis suppurativa) and autoimmune skin diseases (alopecia areata, vitiligo, bullous diseases). Even if the role of IL‐17 in inflammatory and autoimmune diseases has been reported extensively, its role in tumor is still controversial. Some reports show that Th17 cells eradicate tumors, while others reveal that they promote the initiation and early growth of tumors. Herein, we review the role of IL‐17 in the involvement of some common dermatologic diseases: psoriasis, atopic dermatitis, hidradenitis suppurativa, acne, vitiligo, melanoma, and nonmelanoma skin cancers.

Possible role of interleukin 21 and interleukin 33 in patients with genital warts

Genital warts (GWs) are most prevalent sexually transmitted infections, presenting especially among the sexually active young population of both sexes. Efficient cell-mediated immunity is needed for regression of GWs. To clarify the reactivity of cellular immunity among patients with GWs by means of measurements of their levels of serum interleukin (IL)-21 and IL-33, hence, to identify the possible role of IL-21 and IL-33 in GWs, this study aimed to evaluate serum levels of IL-21 and IL-33 among patients with GWs in comparison with the results of the controls. Levels of serum IL-21 and IL-33 were assayed utilizing commercially enzyme-linked immune-sorbent assay kits in 45 patients with GWs and 45 healthy control subjects. Levels of serum IL-21 and IL-33 were significantly decreased among patients with GWs in comparison with the controls (p < .0001). There was a highly significant positive correlation between IL-21 and IL-33 (r = .73, p < .0001). Low levels of serum IL-21 and IL-33 could have a contributive role in development, persistence, severity, and recurrence of GWs which rely basically on the defectiveness of cell-mediated immunity. This could receive new light on nonconventional strategies for the prospective medical therapies of GWs by means of regulation of IL-21 and IL-33.

Learning From Success and Failure: Biologics for Non-approved Skin Diseases

The impressive potential of biologics has been demonstrated in psoriasis, hidradenitis suppurativa, and urticaria. Numerous biologicals are entering the field for a restricted number of skin disorders. Off-label use of biologics in other recalcitrant skin diseases has increased. Mounting data point to the potential of already existing biologics acting on the IL-17/IL-23 pathway in skin disorders with epidermal hyperkeratosis (e.g., pityriasis rubra pilaris), acneiform inflammation (e.g., hidradenitis suppurativa), and loss of mucosal integrity (e.g., aphthosis). TNF-α blockers are also effective in the latter conditions but seem of particular value in granulomatous (e.g., granuloma annulare) and neutrophilic disorders (e.g., pyoderma gangrenosum). Failure of IL-17 blockade in skin diseases resulting from immune-mediated cell destruction (e.g., alopecia areata and vitiligo) illustrates its limited involvement in Th1-dependent skin immunology. Overall, disappointing results of TNF-α blockers in alopecia areata and vitiligo point to the same conclusion although promising results in toxic epidermal necrolysis suggest TNF-α exerts at least some in vivo Th1-related activities. Acting on both the Th1 and Th17 pathway, ustekinumab has a rather broad potential with interesting results in lupus and alopecia areata. The efficacy of omalizumab in bullous pemphigoid has revealed an IgE-mediated recruitment of eosinophils leading to bullae formation. Reconsidering reimbursement criteria for less common but severe diseases seems appropriate if substantial evidence is available (e.g., pityriasis rubra pilaris). For other disorders, investigator- and industry-initiated randomized clinical trials should be stimulated. They are likely to improve patient outcome and advance our understanding of challenging skin disorders.

Alopecia areata is characterized by dysregulation in systemic type 17 and type 2 cytokines, which may contribute to disease-associated psychological morbidity

BACKGROUND

Alopecia areata (AA) is a common autoimmune disease, causing patchy hair loss that can progress to involve the entire scalp (totalis) or body (universalis). CD8⁺ NKG2D⁺ T cells dominate hair follicle pathogenesis, but the specific mechanisms driving hair loss are not fully understood.

OBJECTIVES

To provide a detailed insight into the systemic cytokine signature associated with AA, and to assess the association between cytokines and depression.

METHODS

We conducted multiplex analysis of plasma cytokines from patients with AA, patients with psoriatic arthritis (PsA) and healthy controls. We used the Hospital Anxiety and Depression Scale (HADS) to assess the occurrence of depression and anxiety in our cohort.

RESULTS

Our analysis identified a systemic inflammatory signature associated with AA, characterized by elevated levels of interleukin (IL)-17A, IL-17F, IL-21 and IL-23 indicative of a type 17 immune response. Circulating levels of the type 2 cytokines IL-33, IL-31 and IL-17E (IL-25) were also significantly increased in AA. In comparison with PsA, AA was associated with higher levels of IL-17F, IL-17E and IL-23. We hypothesized that circulating inflammatory cytokines may contribute to wider comorbidities associated with AA. Our assessment of psychiatric comorbidity in AA using HADS scores showed that 18% and 51% of people with AA experienced symptoms of depression and anxiety, respectively. Using linear regression modelling, we identified that levels of IL-22 and IL-17E are positively and significantly associated with depression.

CONCLUSIONS

Our data highlight changes in both type 17 and type 2 cytokines among people with AA, suggesting that complex systemic cytokine profiles may contribute both to the pathogenesis of AA and to the associated depression. What's already known about this topic? NKG2D⁺ CD8⁺ T cells cause hair loss in alopecia areata (AA) but the immunological mechanisms underlying the disease are not fully understood. AA is associated with changes in levels of interleukin (IL)-6, tumour necrosis factor-α, IL-1β and type 17 cytokines. Psychiatric comorbidity is common among people with AA. What does this study add? People with AA have increased plasma levels of the type 2 cytokines IL-33, IL-31 and IL-17E (IL-25), in addition to the type 17 cytokines IL-17A, IL-21, IL-23 and IL-17F. Levels of IL-17E and IL-22 positively predict depression score. What is the translational message? AA is associated with increased levels of multiple inflammatory cytokines, implicating both type 17- and type 2 immune pathways. Our data indicate that therapeutic strategies for treating AA may need to address the underlying type 17- and type 2 immune dysregulation, rather than focusing narrowly on the CD8⁺ T-cell response. An immunological mechanism might contribute directly to the depression observed in people with AA.

Serum concentrations of selected proinflammatory cytokines in children with alopecia areata

Introduction

Alopecia areata (AA) is considered an autoimmune disorder characterized by patchy loss of hair from the scalp and other body parts. Many patients develop the disease in childhood.

Aim

To answer the question whether abnormal production of some proinflammatory cytokines (IL-2, IL-6, IL-15, IL-17A and IFNγ) in children with AA may facilitate the development or progression of the disease.

Material and methods

The study group consisted of 42 children with AA, the control group – 37 healthy children. Peripheral venous blood samples were collected from patients with AA and healthy controls and the concentrations of serum cytokines, namely IL-2, IL-6, IL-15, IL-17A, IFN-γ were determined quantitatively by ELISA method.

Results

The serum IL-6, IL-15, IL-17A and IFNγ levels were significantly increased in patients with AA compared with control subjects (p < 0.05). The serum IL-15 level was found to be increased when the total duration of AA was increased (q = 0.30; p = 0.05). The serum cytokine level of IL-17A was found to be decreased when duration of the current episode was longer than 2 years (p < 0.05), but the correlation between IL-17A serum level and duration of the current episode was not confirmed in the Spearman test (q = –0.06; p = 0.68). The serum IL-17A level was found to be significantly decreased when the thyroiditis was present (q = –2.378; p < 0.05).

Conclusions

The increased levels of serum IL-6, IL-15, IL-17A and IFNγ in children suggest imbalance in the serum proinflammatory cytokines production in AA.

Alopecia areata: a review of disease pathogenesis

BACKGROUND

Alopecia areata is a disorder that results in nonscarring hair loss. The psychological impact can be significant, leading to feelings of depression and social isolation. Objectives In this article, we seek to review the pathophysiological mechanisms proposed in recent years in a narrative fashion.

METHODS

We searched MEDLINE and Scopus for articles related to alopecia areata, with a particular emphasis on its pathogenesis.

RESULTS

The main theory of alopecia areata pathogenesis is that it is an autoimmune phenomenon resulting from a disruption in hair follicle immune privilege. What causes this breakdown is an issue of debate. Some believe that a stressed hair follicle environment triggers antigen presentation, while others blame a dysregulation in the central immune system entangling the follicles. Evidence for the latter theory is provided by animal studies, as well investigations around the AIRE gene. Different immune-cell lines including plasmacytoid dendritic cells, natural killer cells and T cells, along with key molecules such as interferon-γ, interleukin-15, MICA and NKG2D, have been identified as contributing to the autoimmune process.

CONCLUSIONS

Alopecia areata remains incurable, although it has been studied for years. Available treatment options at best are beneficial for milder cases, and the rate of relapse is high. Understanding the exact mechanisms of hair loss in alopecia areata is therefore of utmost importance to help identify potential therapeutic targets.

Targeting the IL-23/IL-17 Pathway in Psoriasis: the Search for the Good, the Bad and the Ugly

New promising treatments have been developed for psoriasis that target different parts of the interleukin (IL)-23/IL-17 pathway. This approach is believed to be more disease specific, and sparing the T helper 1 pathway might prevent serious long-term adverse events. Moreover, superior Psoriasis Area and Severity Index improvements are observed, which has redefined treatment goals in psoriasis. The new molecules can be divided into different categories, according to the target: blocking agents can target the upstream cytokine IL-23 or the downstream IL-17. In the latter, a variety of targets exist, such as the ligands IL-17A and IL-17F, or a combination thereof, or a subunit of the receptor, IL-17RA. Each target seems to have its own set of advantages and pitfalls, which will impact the treatment decision in clinical practice. In this review, we summarize the current knowledge on the different inhibitors of the IL-23/IL-17 pathway. Furthermore, we briefly discuss the role of IL-17 in other diseases and comorbidities. Finally, we discuss how comprehensive knowledge is needed for the prescribing physician in order to make the most appropriate therapeutic choice for each individual patient.

Fibroblast cell-based therapy prevents induction of alopecia areata in an experimental model

Alopecia areata (AA) is an autoimmune hair loss disease with infiltration of proinflammatory cells into hair follicles. Current therapeutic regimens are unsatisfactory mainly because of the potential for side effects and/or limited efficacy. Here we report that cultured, transduced fibroblasts, which express the immunomodulatory molecule indoleamine 2,3-dioxygenase (IDO), can be applied to prevent hair loss in an experimental AA model. A single intraperitoneal (IP) injection of IDO-expressing primary dermal fibroblasts was given to C3H/HeJ mice at the time of AA induction. While 60–70% of mice that received either control fibroblasts or vehicle injections developed extensive AA, none of the IDO-expressing fibroblast-treated mice showed new hair loss up to 20 weeks post injection. IDO cell therapy significantly reduced infiltration of CD4⁺ and CD8⁺ T cells into hair follicles and resulted in decreased expression of TNF-α, IFN-γ and IL-17 in the skin. Skin draining lymph nodes of IDO fibroblast-treated mice were significantly smaller, with more CD4⁺ CD25⁺ FoxP3⁺ regulatory T cells and fewer Th17 cells than those of control fibroblast and vehicle-injected mice. These findings indicate that IP injected IDO-expressing dermal fibroblasts can control inflammation and thereby prevent AA hair loss.

Role of T helper 17 cells and T regulatory cells in alopecia areata: comparison of lesion and serum cytokine between controls and patients

BACKGROUND

Alopecia areata (AA) is an organ-specific autoimmune disease with T-cell-mediated attack of hair follicle autoantigens. As T helper 17 (Th17) cells and T regulatory (Treg) cells are crucially involved in the pathogenesis, the role of Th17 and Treg cytokines has not been studied yet.

OBJECTIVE

To determine whether AA is associated with alterations in lesional and serum Th17 and Treg cytokines and studied whether they were associated with clinical type.

METHODS

Scalp skin samples from 45 patients and eight normal controls were obtained for PCR specific for IFN-γ, TNF-α, TGF-β, IL-1, IL-2, IL-4, IL-10, IL-12A, IL-13, IL-17, IL-22 and IL-23. Serum cytokines were measured from 55 patients and 15 normal controls using ELISA.

RESULTS

Lesional IL-17 and IL-22 were significantly increased in patient group. Moreover, positive correlations were shown between lesional IL-17, IL-22 and disease severity. Serum IL-1, IL-17, TNF-α and TGF-β were significantly increased, and positive correlation was shown between serum IL-17 and disease severity.

CONCLUSION

These results showed significantly high Th17 cytokines in both lesion and serum in AA patients, which may highlight a functional role of these cytokines in the pathogenesis of AA.

The Changing Landscape of Alopecia Areata: The Therapeutic Paradigm

Alopecia areata (AA), a prevalent inflammatory cause of hair loss, lacks FDA-approved therapeutics for extensive cases, which are associated with very poor rates of spontaneous hair regrowth and major psychological distress. Current treatments for severe cases include broad immune-suppressants, which are associated with significant adverse effects, precluding long-term use, with rapid hair loss following treatment termination. As a result of the extent of the disease in severe cases, topical contact sensitizers and intralesional treatments are of limited use. The pathogenesis of AA is not yet fully understood, but recent investigations of the immune activation in AA skin reveal Th1/IFN-γ, as well as Th2, PDE4, IL-23, and IL-9 upregulations. Tissue analyses of both animal models and human lesions following broad-acting and cytokine-specific therapeutics (such as JAK inhibitors and ustekinumab, respectively) provide another opportunity for important insights into the pathogenesis of AA. As reviewed in this paper, numerous novel therapeutics are undergoing clinical trials for AA, emphasizing the potential transformation of the clinical practice of AA, which is currently lacking. Dermatologists are already familiar with the revolution in disease management of psoriasis, stemming from better understanding of immune dysregulations, and atopic dermatitis will soon follow a similar path. In light of these recent developments, the therapeutic arena of AA treatments is finally getting more exciting. AA will join the lengthening list of dermatologic diseases with mechanism-targeted drugs, thus changing the face of AA.

The many faces of interleukin-17 in inflammatory skin diseases

Interleukin (IL)-17 is an emerging target for inflammatory skin disorders. Given the remarkable success of its therapeutic inhibition in psoriasis, the pathogenic role of this cytokine is being explored in other immune-mediated diseases. Interestingly, IL-17 is linked to particular skin conditions where its activation coincides with disease flares. The leading hypothesis for its contribution to proinflammatory signalling cascades is driving inflammasome activation. However, IL-17 stimulation also releases a range of noninflammasome-related cytokines from human skin. Furthermore, a role in cytotoxic responses and an important interplay with the microbiome is hypothesized. While treatment failure would be surprising in neutrophilic dermatoses, the picture might be more complex in lymphocyte-mediated conditions. Nonetheless, increasing insights into the pathogenesis suggest that beneficial responses are also probable in the latter conditions. Study of this pathway in the skin reveals some intriguing aspects of the IL-17-related immunological network.

Extreme Phenotype of Epidermal Growth Factor Receptor Inhibitor-induced Destructive Folliculitis

Due to the increasingly widespread use and side effect profile of epidermal growth factor receptor inhibitors (EGFRIs), cutaneous side effects of these drugs are frequently encountered. The EGFR is expressed on keratinocytes and fibroblasts. Inhibition of EGFR can produce a range of cutaneous adverse effects, the most frequent being a characteristic acneiform skin eruption. As the latter is associated with good anti-neoplastic responses, the onset of EGFRI-induced acneiform skin eruption is typically viewed as a positive sign by patients and physicians. It can usually be treated well with standard acne drugs, but in rare cases, the skin eruption can be so severe that systemic therapy and/or interruption of EGFRI treatment are required. One of the severest forms of EGFRI-induced skin eruption occurring on the head and neck area resembles folliculitis decalvans. Here, we discuss the management of such a case seen in our department. In addition, we present an analysis of tumor necrosis factor-α, interleukin-1β (IL-1β), and IL-17A expression based on immunohistochemical stains and qPCR.