Serum defensin levels in patients with systemic sclerosis

Abstract Background: Systemic sclerosis (SSc) is an autoimmune disease characterized by fibrosis of skin and lung as well as involvement of kidney, gastrointestinal system and heart. Aetiology and exact mechanism of disease is poorly understood. The association between antimicrobial peptides (AMPs) and other diseases such as idiopathic pulmonary fibrosis, diffuse panbronchiolitis, pulmoner alveolar proteinosis and psoriasis have been reported. A small number of studies have examined the role of AMPs on autoimmune diseases which has not been studied in scleroderma yet. We aimed to investigate AMP serum levels and their association with disease characteristics of SSc. Methods: Forty-two patients (40 female, mean age 42 years) and 38 healthy subjects (32 female, mean age 38 years) were enrolled. For SSc patients, the following data were recorded: disease subset (limited/diffuse), autoantibodies (antinuclear, anti-centromere (ACA), and anti-SCL-70), blood tests, erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP), modified Rodnan skin score, presence and history of digital ulcers, kidney, gastrointestinal disease and lung involvement assessed by computed tomography and pulmonary function tests. Association between serum AMPs and disease characteristics were analysed. Results: Twenty-nine of the patients had diffuse (69%) and 13 of the patients had limited (31%) systemic sclerosis. Average disease duration was 5.5 years. Pulmonary involvement was detected in 20 patients (47.6%). Serum concentration of alpha defensin was higher than healthy subjects (563 ± 415 vs 377 ± 269 ng/mL, p = 0.02). However, no difference was observed for beta-1 and beta-2 defensins in SSc patients and healthy controls. In sub-group analysis patients with interstitial lung disease had higher levels of alpha defensin than those without lung involvement (684 ± 473 vs 430 ± 299 ng/ml, p = 0.04). There was also correlation between alfa defensin serum concentrations and CRP (r = 0.34). Conclusions: Alpha defensin levels are increased in scleroderma patients and correlated with lung involvement indicating a role in the pathogenesis of disease. Trial registration: This study is not a clinical trial study.(AU)

Effect of gluten diet on blood innate immune gene expressions and stool consistency in Spix's Saddleback Tamarin (Leontocebus fuscicollis) raised in captivity.

The callitrichids are non-human primates that feed on insects and plant matter in nature, but in captivity, they are fed mostly an artificial diet containing amounts of gluten, in their toxic forms in items such as wheat, barley and rye. The aim of this research was to estimate the blood ß-defensin and Toll like receptor 5 (TLR5) gene expressions and to analyze the stool consistency (firm, soft, diarrheic) in Leontocebus fuscicollis raised in captivity. Blood samples of animals under gluten-free and gluten diets were collected and their fecal output quality was periodically monitored and classified during the course of the study. Gene expression was evaluated using real-time PCR. The stool consistencies of individuals fed a gluten diet were most frequently soft or diarrheic, while it was mostly normal in individuals fed a gluten-free diet. ß-Defensin expression increased in individuals fed a gluten diet, but decreased after 15 days. Expression normalized between 30 and 45 days on a gluten-free diet. However, expression of the TLR5 gene did not change under a gluten diet. A gluten diet affects stool quality, and brings about an immediate increase in blood ß-defensin expression in the beginning but decreases after 15 days.

Association of human beta-defensin 1 gene polymorphisms with nonsegmental vitiligo.

BACKGROUND: Vitiligo is a pigmentation disorder of autoimmune aetiology. Polymorphisms in beta-defensin genes have been linked to a predisposition to some autoimmune disorders. AIM: To evaluate the role of polymorphisms in DEFB1, the gene encoding for human beta-defensin (HBD)-1 and its 5' untranslated region in nonsegmental vitiligo. METHODS: In total, 354 participants [171 patients with non-segmental vitiligo and 183 age and sex-matched healthy controls (HCs)], were genotyped by the PCR-restriction fragment length polymorphism (RFLP) method. For 80 of these individuals (40 patients and -40 HCs) serum HBD-1 was also measured by ELISA. RESULTS: The -44 G allele, CG genotype and GGG haplotype increased the risk for vitiligo (P < 0.02 in all cases), whereas the -20 AA genotype seems to be protective (P = 0.04). Serum HBD-1 levels were lower in patients with vitiligo than in HCs (P < 0.01), as well as in patients with active vitiligo compared with those with stable vitiligo and with HCs (P < 0.05 in both cases), CONCLUSION: Our results suggest that HBD-1 and its gene polymorphisms may modulate vitiligo susceptibility and/or disease activity. This is the first report, to our knowledge, of the association of serum HBD-1 levels and DEFB1 gene polymorphisms with vitiligo.

Differences in Cytokine Production during Aging and Its Relationship with Antimicrobial Peptides Production.

Aging is a major health issue due to the increased susceptibility of elderly people to infectious, autoimmune, and cardiovascular diseases. Innate immunity is an important mechanism to avoid primary infections; therefore, decreasing of its activity may lead to development of infections. Antimicrobial peptides (AMPs) are effector molecules of innate immunity that can eliminate microbial invaders. The role that cytokines play in the regulation of these innate immune mechanisms needs to be explored. Serum determinations of Th1, Th2, and Th17 cytokines were performed in order to evaluate their association with AMPs human beta-defensin (HBD)-2 and LL-37 in young adults, elder adults, and elder adults with recurrent infections. Our results showed differences in interleukin (IL)-10 and IL-6 among the different groups. Inverse correlations in serum cytokine levels and HBD-2 production were identified for IL-10, IL-2, IL-4, tumor necrosis factor-α, and IL-6. Also inverse correlations were identified for IL-10, IL-4, and cathelicidin (LL-37). Such results could impact the development of immunomodulators that promote AMP production to prevent and/or contain infectious diseases in this population.

Differential expression of antimicrobial peptides in active and latent tuberculosis and its relationship with diabetes mellitus.

Tuberculosis (TB) is one of the most important infectious diseases, causing 1.8 million deaths annually worldwide. This problem has increased because of the association with human immmunodeficiency virus and diabetes mellitus type 2, mainly in developing countries. In the past few years it has been highlighted the significance of antimicrobial peptides in the immunopathogenesis of TB ex vivo and in experimental models studies. In this study we analyzed the expression of CAMP, DEFA1, DEFB4, and DEFB103A in patients with latent TB and progressive TB with and without comorbidity with diabetes mellitus type 2. Antimicrobial peptide gene expression increased during progressive TB, which could be used as a biomarker for reactivation. By contrast, patients with diabetes mellitus type 2 have lower antimicrobial peptides gene expression, suggesting that the lack of its proper production in these patients contribute to enhance the risk for TB reactivation.