Circulatory levels of alarmins in patients with non-segmental vitiligo: Potential biomarkers for disease diagnosis and activity/severity assessment

HMGB1: new biomarker and therapeutic target of autoimmune and autoinflammatory skin diseases

High-mobility group box 1 (HMGB1) is expressed in almost all human cells. During cell activation and cell death, the nucleoprotein HMGB1 can translocate to the extracellular space, thus mediating the early inflammatory response as an alarmin or damage-associated molecular pattern (DAMP). Extracellular HMGB1 interacts with immune cells by binding to pattern recognition Toll-like receptors (TLRs), including TLR2 and TLR4, and the receptor for advanced glycation end products (RAGE), thus mediating the immune response to protect the host against pathogens and maintain immune balance. HMGB1 is reportedly upregulated and is a critical biomarker for monitoring disease activity in several chronic inflammatory or autoimmune disorders, including multiple sclerosis, rheumatoid arthritis, inflammatory bowel disease, systemic lupus erythematosus and vitiligo. Additionally, the inhibition of HMGB1 expression or its activity has beneficial effects on disease activity in animal models of autoimmune diseases. Thus, HMGB1 is an indispensable biomarker and an important therapeutic target for autoimmune diseases. This review provides a detailed summary of the biological function of HMGB1 and provides a comprehensive outlook in terms of HMGB-focused diagnostic and therapeutic applications in autoimmune skin diseases.

Focusing on the Dark Side of the Moon: Involvement of the Nonlesional Skin in Vitiligo

Research over the last decade has revealed that the normally pigmented skin of patients with vitiligo is not normal at all, as evidenced by alterations in cutaneous morphology and modifications in cellular and metabolic functions that ultimately drive immune activation against melanocytes. Furthermore, nonlesional skin is in a state of subclinical inflammation until triggered by internal and/or external exposomal events. Therefore, targeting early processes that drive immune dysregulation in normally pigmented skin may avoid or reduce melanocyte loss. Thus, shifting the focus to nonlesional skin may prevent the appearance of clinical manifestations of the disease rather than treating the lesions.

Evaluation of neutrophil activation marker in patients with vitiligo

BACKGROUND

Vitiligo is an inflammatory, autoimmune disorder. Its pathogenesis is unclear. A neutrophil activation marker (calprotectin) is a protein complex present in many different types of cells and may be used as an indicator of inflammation.

AIMS

This study is to assess calprotectin levels in non-segmental vitiligo patients and compare them to the severity of the illness to identify potential associations.

METHODS

The present inquiry was conducted on thirty non-segmental vitiligo patients and thirty healthy volunteers matched in terms of age and gender. The Vitiligo Area Scoring Index was used to assess the vitiligo severity. Calprotectin levels were measured in serum samples obtained from all participants by Enzyme Linked Immunosorbent Assay.

RESULTS

Compared to controls, non-segmental vitiligo patients had considerably elevated serum calprotectin levels. Additionally, calprotectin levels were shown to have a significant positive association with disease severity (r = 0.833, P = 0.000).

CONCLUSIONS

Elevated levels of serum calprotectin in non-segmental vitiligo patients relative to healthy individuals with high sensitivity indicated that it may have a role in the vitiligo pathophysiology and can act as a marker for disease monitoring.

Exploring the Role of Adipose Tissue Dysregulation in Vitiligo Pathogenesis: A Body Composition Analysis

Vitiligo is a commonly acquired pigmentary disease characterized by the progressive destruction of melanocytes. The role of adipose tissue in vitiligo remains unclear. To investigate the role of adipose tissue in the pathogenesis of vitiligo, 50 patients newly diagnosed with vitiligo and 40 age- and sex-matched healthy controls were enrolled, and fat mass and distribution using dual-energy X-ray absorptiometry (DXA) and serum adipokine levels using enzyme-linked immunosorbent assay were assessed. The trunk and whole-body fat mass and the trunk/limb fat mass ratio were significantly higher in patients with vitiligo. Higher leptin and resistin levels and lower adiponectin levels were observed. Positive correlation of the trunk fat mass index with vitiligo area scoring index scores (r = 0.38, p = 0.0071) was found. Additionally, plasma adiponectin levels were negatively correlated with vitiligo disease activity scores (r = -0.307, p < 0.05). Receiver operating characteristic curve analysis showed that the percentage of limb lean tissue mass, trunk/limb fat mass ratio, and serum adipokine levels achieved a high area under the curve score for distinguishing patients with vitiligo from healthy controls. In conclusion, the incidence of central obesity and adipokine dysregulation was higher in patients with vitiligo. The potential role of adipose tissue in the pathogenesis of vitiligo should be emphasized.

Circulating memory T cells and TCF1+ T cells aid in diagnosis and monitor disease activity in vitiligo

Vitiligo is an immune memory skin disease. T-cell factor 1 (TCF1) is essential for maintaining the memory T-cell pool. There is an urgent need to investigate the characteristics of peripheral memory T-cell profile and TCF1+ T-cell frequencies in patients with vitiligo. In this study, 31 patients with active vitiligo (AV), 22 with stable vitiligo (SV), and 30 healthy controls (HCs) were included. We measured circulating memory and TCF1+ T-cell frequencies using flow cytometry. The Spearman's rank test was used to evaluate the correlation between cell frequencies and disease characteristics. Receiver operating characteristic curves (ROC) were constructed to investigate the discriminative power of the cell subpopulations. Circulating CD4+ and CD8+ terminally differentiated effector memory T-cell (TEMRA) frequencies were significantly higher in the AV group than in HCs (P < 0.05). TCF1+ T-cell subpopulations were widespread increased in patients with vitiligo (P < 0.05). After adjusting for potential confounders, CD8+ and CD4+ central memory (TCM) cells, and CD8+ TEMRA were correlated with disease activity (P < 0.05). The combined diagnostic value of the four (naïve, effector memory, TCM, and TEMRA) CD8+TCF1+ T-cell subsets was relatively high (area under the ROC curve (AUC) = 0.804, sensitivity = 71.70%, specificity = 83.34%), and the CD8+ T-cell subsets combination performed well in discriminating disease activity (AUC = 0.849, sensitivity = 70.97%, specificity = 90.91%). We demonstrated an altered circulating memory T-cell profile and increased TCF1+ T-cell percentage in patients with vitiligo. T-cell subpopulations had a strong value for vitiligo diagnosis and activity evaluation. This evidence presents a potential new pharmacological target for inhibiting autoimmunity that leads to vitiligo.

Serum Calprotectin Levels in Vitiligo Patients and Disease Relation

INTRODUCTION

Vitiligo is characterized as melanocyte loss in skin and mucous membranes, the pathogenesis of which has not yet been clarified. Calprotectin is a protein secreted from neutrophils, monocytes, and dendritic cells which has an effect on cytokine receptor regulation and the production of reactive oxygen radicals. It has been the subject of research in various inflammatory and autoimmune diseases, yet not investigated in vitiligo.

OBJECTIVE

The aim of our study was to investigate the role of calprotectin in the etiopathogenesis of vitiligo and its relationship with clinical subtypes and disease scores.

METHODS

Forty-four vitiligo patients with lack of autoimmune disease and 36 age- and sex-matched healthy controls were involved in the study. Serum calprotectin levels were measured by ELISA. The results were compared with the control group, and the relationship between patients' demographic characteristics, skin phototypes, disease type, disease scores (Vitiligo Area Scoring Index and Vitiligo Disease Activity Score), disease duration, and age at onset were evaluated.

RESULTS

The median serum calprotectin level was 454.08 pg/ml (41.19-873.41) in the patient group, and the median serum calprotectin level was 223.17 pg/ml (44.88-1044.43) in the control group. Serum calprotectin level was significantly higher in the patient group than in the control group (P = 0.016). No correlation was found between serum calprotectin level and disease scores, disease duration, age, or age of onset of disease (P > 0.05).

CONCLUSIONS

In our study, serum calprotectin levels in the patient group were found to be significantly higher than in the control group. Our findings and the existing literature on calprotectin suggest its potential involvement in the pathogenesis of vitiligo, independent of disease progression and patient characteristics.

Precision Dermatology: A Review of Molecular Biomarkers and Personalized Therapies

The evolution of personalized medicine in dermatology signifies a transformative shift towards individualized treatments, driven by the integration of biomarkers. These molecular indicators serve beyond diagnostics, offering insights into disease staging, prognosis, and therapeutic monitoring. Specific criteria guide biomarker selection, ensuring attributes like specificity, sensitivity, cost feasibility, stability, rapid detection, and reproducibility. This literature review, based on data from PubMed, SCOPUS, and Web of Science, explores biomarkers in Hidradenitis Suppurativa (HS), Psoriasis, Atopic Dermatitis (AD), Alopecia Areata (AA), Vitiligo, and Chronic Spontaneous Urticaria (CSU). In HS, TNF-α, IL-1β, and MMPs serve as biomarkers, influencing targeted therapies like adalimumab and anakinra. Psoriasis involves biomarkers such as TNF-α, IL-23, and HLA genes, shaping treatments like IL23 and IL17 inhibitors. AD biomarkers include ECP, IL-4, IL-13, guiding therapies like dupilumab and tralokinumab. For AA, lipocalin-2, cytokines, and genetic polymorphisms inform JAK inhibitors' use. Vitiligo biomarkers range from cytokines to genetic markers like TYR, TYRP1, guiding treatments like JAK inhibitors. CSU biomarkers encompass IgE, cytokines, and autologous serum tests, influencing therapies like omalizumab and cyclosporine. Comparing conditions, common proinflammatory markers reveal limited specificity. While some biomarkers aid diagnosis and standard treatments, others hold more scientific than clinical value. Precision medicine, driven by biomarkers, has shown success in skin malignancies. Future directions involve AI-powered algorithms, nanotechnology, and multi-omics integration for personalized dermatological care.