Elevated serum level of interleukin-15 in vitiligo patients and its correlation with disease severity but not activity.

BACKGROUND: Vitiligo is a common acquired disorder of depigmentation. Its pathogenesis entails a T helper (Th) 1-cytotoxic T (cT) lymphocytes mediated autoimmune melanocyte destruction. Interleukin (IL)-15 is one of the IL-2 family of cytokines and shares several actions with IL-2. IL-15 enhances survival, maturation, and functional activity of natural killer, neutrophils, and dendritic cells. Furthermore, it potentiates survival, maturation, and cytotoxicity of memory cT cells. IL-15 has been shown to play a crucial role in the pathogenesis of several autoimmune diseases but was poorly investigated in patients with vitiligo. AIMS: The study aimed at evaluating IL-15 level in the sera of patients with vitiligo and its association with vitiligo severity and activity. PATIENTS AND METHODS: The study included 30 patients with nonsegmental vitiligo and 30 healthy controls. Vitiligo Extent Score (VES) and Vitiligo Disease Activity (VIDA) score were used to assess vitiligo severity and activity, respectively. Serum level of IL-15 was assessed by enzyme-linked immune-sorbent assay. RESULTS: Serum IL-15 level, in patients with vitiligo, was significantly higher in comparison with the control group (P = .001). A significant positive correlation was found between serum IL-15 level and VES score (P = .001), whereas there was no significant correlation between IL-15 level and VIDA score as well as the disease duration. CONCLUSION: IL-15 level was elevated in the sera of patients with vitiligo. IL-15 may therefore have a significant impact on vitiligo autoimmune pathogenesis, and further identification of its molecular roles may highlight new therapeutic strategies for vitiligo.

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.

BACKGROUND: Alopecia areata (AA) is an organ-specific autoimmune disease characterized by T-cell infiltrates and cytokine production. T-helper 17 (Th17) cells are crucially involved in the pathogenesis of autoimmune diseases. OBJECTIVES: Our aim was to assess the association of Th17 with AA. We examined interleukin (IL)-17, IL-21, IL-22, IL-6, and tumor necrosis factor-alpha (TNF-α) levels in the serum of patients with AA and studied their association with clinical type and severity of AA. SUBJECTS AND METHODS: The serum concentrations of IL-17, IL-21, IL-22, IL-6, and TNF-α were measured in 47 patients with AA and 40 healthy controls. The clinical type of AA was determined, and the severity of hair loss was assessed in accordance with the Alopecia Areata Investigational Assessment Guideline criteria. RESULTS: The serum concentrations of IL-17, IL-21, IL-22, IL-6, and TNF-α were significantly higher in patients with AA as compared with healthy controls (mean: IL-17 33.23 ± 11.58 vs. 4.62 ± 1.88 pg/ml; P = 0.000, IL-21 62.10 ± 6.11 vs. 48.38 ± 3.31 pg/ml; P = 0.000, IL-22 19.27 ± 3.36 vs. 7.09 ± 1.62 pg/ml; P = 0.000, IL-6 17.18 ± 3.08 vs. 4.59 ± 1.66 pg/ml; P = 0.000, TNF-α 19.94 ± 3.59 vs. 9.95 ± 2.42 pg/ml; P = 0.000, respectively). There were significant positive correlations between serum IL-17, TNF-α, and disease severity. There was also significant positive correlation between serum IL-22 and duration of AA. CONCLUSION: Our results showed high serum levels of Th17 cytokines among patients with AA that may suggest a functional role of these cytokines in the pathogenesis of this important skin disease. It could also provide the rationale for new treatment strategies in AA.

Serum leptin, adiponectin, and resistin among adult patients with acanthosis nigricans: correlations with insulin resistance and risk factors for cardiovascular disease.

BACKGROUND: Acanthosis nigricans (AN) is linked to obesity and insulin resistance. Major adipokines such as leptin, adiponectin, and resistin are known to be dysregulated in obesity and are key players in the pathogenesis of metabolic syndrome. OBJECTIVES: This study was conducted to assess serum levels of the major adipokines leptin, adiponectin, and resistin, and to study their correlations with the state of insulin resistance and other risk factors for cardiovascular disease (CVD) among AN patients. METHODS: A total of 115 adult subjects were included in the study; 52 of these had benign acquired AN, and 63 (control subjects) were without AN. Thirty-three of the control group were obese, and 30 were healthy subjects of normal weight. Body mass index (BMI), blood pressure, lipid profile, fasting blood glucose, fasting insulin, serum leptin, adiponectin, and resistin were assessed in all subjects. RESULTS: We found significant differences between AN patients and obese controls in serum levels of leptin (30.02 ± 15.14 ng/ml vs. 21.07 ± 7.92 ng/ml; P = 0.002), adiponectin (5.55 ± 2.89 µg/l vs. 9.02 ± 2.33 µg/ml; P = 0.00001), and resistin (20.88 ± 3.97 ng/ml vs. 16.82 ± 4.36 ng/ml; P = 0.00003). Significant positive correlations were found between serum leptin and homeostasis model assessment (HOMA) value, insulin, glucose, BMI, cholesterol, and low-density lipoprotein. There were also significant negative correlations between adiponectin and HOMA value, insulin, BMI, cholesterol, and leptin among AN patients. CONCLUSIONS: Acanthosis nigricans is a likely forerunner of the finding of metabolic syndrome. High serum leptin and resistin and low serum adiponectin may increase the risk for CVD among AN patients.