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Adv Rheumatol ; 60: 54, 2020. tab
Article in English | LILACS | ID: biblio-1152730


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)

Humans , Scleroderma, Systemic/pathology , Antimicrobial Cationic Peptides/blood , alpha-Defensins/blood , beta-Defensins/blood , Lung Diseases/etiology
Chinese Medical Journal ; (24): 2966-2975, 2020.
Article in English | WPRIM | ID: wpr-877923


Antimicrobial peptides (AMPs) are small molecules produced by a myriad of cells and play important roles not only in protecting against infections and sustaining skin barrier homeostasis but also in contributing to immune dysregulation under pathological conditions. Recently, increasing evidence has indicated that AMPs, including cathelicidin (LL-37), human β-defensins, S100 proteins, lipocalin 2, and RNase 7, are highly expressed in psoriatic skin lesions. These peptides broadly regulate immunity by interacting with various immune cells and linking innate and adaptive immune responses during the progression of psoriasis. In this review, we summarize the recent findings regarding AMPs in the pathogenesis of psoriasis with a main focus on their immunomodulatory abilities.

Adaptive Immunity , Humans , Immunity, Innate , Pore Forming Cytotoxic Proteins , Psoriasis , Skin Diseases , beta-Defensins
Article in English | WPRIM | ID: wpr-828965


Efforts to control inflammation and achieve better tissue repair in the treatment of periodontitis have been ongoing for years. Human β-defensin 3, a broad-spectrum antimicrobial peptide has been proven to have a variety of biological functions in periodontitis; however, relatively few reports have addressed the effects of human periodontal ligament cells (hPDLCs) on osteogenic differentiation. In this study, we evaluated the osteogenic effects of hPDLCs with an adenoviral vector encoding human β-defensin 3 in an inflammatory microenvironment. Then human β-defensin 3 gene-modified rat periodontal ligament cells were transplanted into rats with experimental periodontitis to observe their effects on periodontal bone repair. We found that the human β-defensin 3 gene-modified hPDLCs presented with high levels of osteogenesis-related gene expression and calcium deposition. Furthermore, the p38 MAPK pathway was activated in this process. In vivo, human β-defensin 3 gene-transfected rat PDLCs promoted bone repair in SD rats with periodontitis, and the p38 mitogen-activated protein kinase (MAPK) pathway might also have been involved. These findings demonstrate that human β-defensin 3 accelerates osteogenesis and that human β-defensin 3 gene modification may offer a potential approach to promote bone repair in patients with periodontitis.

Animals , Anti-Infective Agents , Metabolism , Pharmacology , Cell Differentiation , Cells, Cultured , Humans , Osteogenesis , Periodontal Ligament , Metabolism , Periodontitis , Drug Therapy , Rats , Rats, Sprague-Dawley , beta-Defensins , Metabolism , Pharmacology
Article in English | WPRIM | ID: wpr-812995


OBJECTIVES@#To investigate the effect of icariin (ICA) on early β-defensin-2 and T cell subsets in rats after tracheotomy.@*METHODS@#A total of 54 SPF male Sprague-Dawley rats were randomly divided into a normal control group (group A), a model group (group B), and a model+ICA treatment group (group C), with 18 rats in each group. A tracheotomy intubation model of the B and C group was prepared. After 6 h of surgery, ICA intervention was given to group C. Groups A and B were given the same amount of normal saline. Lung tissue, alveolar lavage fluid and peripheral blood were taken at 24 h, 72 h and 168 h, respectively. The expression of rat β-defensin-2 mRNA in lung tissue was detected by RT-PCR. The content of β-defensin-2 in alveolar lavage fluid and peripheral blood serum was detected by ELISA. The content of peripheral blood T cell subsets (CD3, CD4, CD8) was detected by flow cytometry, and the ratio of CD4/CD8 was calculated.@*RESULTS@#After tracheotomy, the levels of β-defensin-2 mRNA and β-defensin-2 in lung tissue from the group B were increased significantly at 24 h, then they were decreased gradually, and decreased most significantly at 168 h (0.05). The level of CD3 T cells in peripheral blood was significantly lower than that in the group A (0.05). After ICA intervention in group C: lung tissue, alveolar lavage fluid, peripheral blood serum β-defensin-2 content, and peripheral blood CD3 and CD4 T cell levels were gradually increased, significantly higher than those in the group B (<0.05). CD8 T cell level was significantly lower than that in the group A at 24 h (<0.05), the CD4/CD8 ratio was significantly higher at 168 h than those in the group A or B (both <0.01).@*CONCLUSIONS@#ICA can improve the early lung immune function in rats with tracheotomy, which might be related to up-regulation of β-defensin-2 in lung tissue and alveolar lavage fluid, concomitant with increases in CD3 and CD4 T cells and CD4/CD8 ratio in peripheral blood while reduction in CD8 cells.

Animals , Flavonoids , Male , Rats , Rats, Sprague-Dawley , T-Lymphocyte Subsets , Tracheotomy , beta-Defensins
Article in Chinese | WPRIM | ID: wpr-772004


OBJECTIVE@#To investigate the association between the polymorphisms of 5'-UTR -52G/A (rs1799946), -44C/G (rs1800972), -20G/A (rs11362) in DEFB1 gene with chronic periodontitis in Henan Han population.@*METHODS@#Peripheral blood genomic DNA of 436 patients with chronic periodontitis and 440 healthy controls were extracted and subjected to PCR-Sanger sequencing to determine the genotypes of DEFB1 5'-UTR -52G/A (rs1799946), -44C/G (rs1800972) and -20G/A (rs11362). The distribution of genotypes, allele frequencies and risk factors were analyzed by chi-square test and Logistic regression.@*RESULTS@#There was no significant difference between healthy controls and chronic periodontitis in the genotype of -52G/A PCR- (rs1799946) and -20G/A (rs11362) (P> 0.05). While a significant difference was found between healthy controls and chronic periodontitis in -44C/G (rs1800972), the CC and CG genotype rate in the two groups were 64.5%, 82.1% and 28.2%, 14.4% respectively. One-way logistic analysis showed that the CG, GG genotype and allele G might be a protective factor.@*CONCLUSION@#The DEFB1 -44C/G (rs1800972) is associated with chronic periodontitis in Henan Han population, and the -44CG, GG genotype and G allele may be the protective factors of chronic periodontitis in Henan Han population.

Alleles , Case-Control Studies , Chronic Periodontitis , Genetics , Gene Frequency , Genetic Predisposition to Disease , Genotype , Humans , Polymorphism, Genetic , beta-Defensins , Genetics
Chinese Journal of Biotechnology ; (12): 1088-1096, 2019.
Article in Chinese | WPRIM | ID: wpr-771819


To improve and broaden the antimicrobial activity of β-defensin130, 3 copies of β-defensin130 encoding sequences were synthesized and cloned into pET28a (+) expression vector, and expressed in Escherichia coli BL21 (DE3) as a 25 kDa soluble protein. The affinity purified 3×β-defensin 130 displayed antimicrobial activity against not only Gram-positive strains including Staphylococcus aureus (ATCC 25923) (45 μg/mL) and Listeria monocytogenes (ATCC 221633) (80 μg/mL) but also Gram-negative strains. Furthermore, the antimicrobial activity of β-defensin130 was not affected by temperature, pH and proteinase digestion. In addition, E. coli-derived 3×β-defensin130 was not toxic to HEK 293 cells and showed a relatively low hemolytic activity against rabbit erythrocytes. Our study proves 3×β-defensin130 expressed in E. coli is stable, non-cytotoxic and low-hemolytic active with great potential as alternative antibiotics.

Animals , Anti-Bacterial Agents , Escherichia coli , HEK293 Cells , Humans , Rabbits , Recombinant Fusion Proteins , Staphylococcus aureus , beta-Defensins
Chinese Journal of Biotechnology ; (12): 1469-1477, 2019.
Article in Chinese | WPRIM | ID: wpr-771782


The aim of this study was to screen the active regions and transcription factor binding sites in the promoter of the CBD103 gene related to Arctic fox coat color, and to provide a basis for revealing the molecular genetic mechanism of CBD103 gene regulating the coat color formation. The 5'-flanking region fragment 2 123 bp of Arctic fox CBD103 gene was cloned, and 4 truncated promoter reporter vectors of different lengths were constructed. The promoter activity was detected by the dual-luciferase reporter assay system. Point mutations were performed on the 3 predicted specificity protein 1 (Sp1) transcription factor binding sites in the highest promoter active region, and 3 mutant vectors were constructed. The activity was then detected by the dual-luciferase reporter assay system. The results showed that the region 1 656 (-1 604/+51) had the highest activity in the 4 truncated promoters of different lengths, and the promoter activity of the three mutant vectors constructed in this region were significantly lower than that of the wild type (fragment 1 656). The region of -1 604 /+51 was the core promoter region of CBD103 gene in Arctic fox and -1 552/-1 564, -1 439/-1 454 and -329/-339 regions were positive regulatory regions. This study successfully obtained the core promoter region and positive regulation regions of the Arctic fox CBD103 gene, which laid a foundation for further study on the molecular genetic mechanism of this gene regulating Arctic fox coat color.

Animals , Binding Sites , Foxes , Luciferases , Promoter Regions, Genetic , Sp1 Transcription Factor , beta-Defensins
ImplantNewsPerio ; 3(1): 105-108, jan.-fev. 2018.
Article in Portuguese | LILACS, BBO | ID: biblio-881702


Objetivo: as beta-defensinas humanas (hBDs) podem ter um papel-chave na susceptibilidade às doenças na cavidade bucal. Além do efeito antimicrobiano direto, as hBDs aumentam a imunidade adaptativa. O objetivo deste estudo foi realizar uma revisão de literatura científica sobre a relação entre beta-defensinas (hBD) e periodontite. Material e métodos: foi realizada uma pesquisa bibliográfica na base de dados PubMed sobre a expressão de hBDs em indivíduos com periodontite. Os termos beta defensins e periodontitis foram utilizados nessa busca. Resultados: foram selecionados, por um revisor, sete artigos para serem incluídos nessa revisão de literatura: dois estudos de intervenção e cinco estudos transversais. Conclusão: o número de estudos sobre a expressão de beta-defensinas em indivíduos com periodontite é reduzido. O conhecimento sobre o papel das beta-defensinas na periodontite pode trazer um maior entendimento de sua etiopatogenia, além de possibilitar novos indicadores de risco e terapias. Estudos adicionais são necessários para a elucidação da relação entre esses peptídeos antimicrobianos e a periodontite.

Objective: human beta-defensins (hBDs) may play a key role in the susceptibility to diseases in the oral cavity. In addition to the direct antimicrobial effect, hBDs enhance adaptive immunity. The objective of this study was to investigate the literature on the relationship between hBD and periodontitis. Material and methods: a literature review was conducted in the PubMed database on the expression of hBDs in subjects with periodontitis. The terms "beta-defensins" and "periodontitis" were used in this search. Results: seven articles were selected being: two intervention studies and fi ve cross-sectional studies. Conclusion: the number of studies on the expression of beta-defensins in individuals with periodontitis is reduced. Knowledge about the role of beta-defensins in periodontitis may lead to a better understanding of their etiopathogenesis, in addition to providing new risk indicators and therapies. Additional studies are needed to elucidate the relationship between these antimicrobial peptides and periodontitis.

Humans , Male , Female , beta-Defensins , beta-Defensins/immunology , Periodontitis , Periodontitis/complications
Frontiers of Medicine ; (4): 717-725, 2018.
Article in English | WPRIM | ID: wpr-772714


Psoriasis (Ps) is an inflammatory skin disease caused by genetic and environmental factors. Previous studies on DNA methylation (DNAm) found genetic markers that are closely associated with Ps, and evidence has shown that DNAm mediates genetic risk in Ps. In this study, Consensus Clustering was used to analyze DNAm data, and 114 Ps patients were divided into three subclassifications. Investigation of the clinical characteristics and copy number variations (CNVs) of DEFB4, IL22, and LCE3C in the three subclassifications revealed no significant differences in gender ratio and in Ps area and severity index (PASI) score. The proportion of late-onset ( ≥ 40 years) Ps patients was significantly higher in type I than in types II and III (P = 0.035). Type III contained the smallest proportion of smokers and the largest proportion of non-smoking Ps patients (P = 0.086). The CNVs of DEFB4 and LCE3C showed no significant differences but the CNV of IL22 significantly differed among the three subclassifications (P = 0.044). This study is the first to profile Ps subclassifications based on DNAm data in the Chinese Han population. These results are useful in the treatment and management of Ps from the molecular and genetic perspectives.

Adolescent , Adult , Aged , Asians , Genetics , Case-Control Studies , Child , China , Cornified Envelope Proline-Rich Proteins , Genetics , DNA Copy Number Variations , DNA Methylation , Female , Genetic Predisposition to Disease , Humans , Interleukins , Genetics , Male , Middle Aged , Psoriasis , Classification , Genetics , Risk Factors , Young Adult , beta-Defensins , Genetics
Article in Chinese | WPRIM | ID: wpr-300359


<p><b>OBJECTIVE</b>To study the effect of Bifidobacterium on the expression of β-defensin-2 (BD-2) in intestinal tissue of neonatal rats with necrotizing enterocolitis (NEC).</p><p><b>METHODS</b>A total of 40 rats were randomly divided into four groups: normal control, Bifidobacterium control, NEC model, and Bifidobacterium treatment, with 10 rats in each group. A rat model of NEC was induced by hypoxia, cold stimulation, and artificial feeding. The rats in the Bifidobacterium control and Bifidobacterium treatment groups were given Bifidobacterium via the gastric tube after cold stimulation once a day for three consecutive days. The morphological changes of the terminal ileum were observed under a light microscope and the intestinal injury score was determined. Immunohistochemistry and qRT-PCR were used to measure the protein and mRNA expression of BD-2 in the ileal mucosal tissue.</p><p><b>RESULTS</b>The NEC model group had a significantly higher intestinal injury score than the normal control, Bifidobacterium control, and Bifidobacterium treatment groups (P<0.05). The Bifidobacterium treatment group had a significantly higher intestinal injury score than the normal control and Bifidobacterium control groups (P<0.05). The mRNA and protein expression of BD-2 in the normal control group was significantly lower than in the Bifidobacterium control, NEC model, and Bifidobacterium treatment groups (P<0.05). The Bifidobacterium control group had significantly higher mRNA and protein expression of BD-2 than the NEC model and Bifidobacterium treatment groups (P<0.05). The Bifidobacterium treatment group had significantly higher mRNA and protein expression of BD-2 than the NEC model group (P<0.05).</p><p><b>CONCLUSIONS</b>Bifidobacterium can induce the expression of BD-2 in intestinal tissue of rats and reduce inflammatory response by increasing the expression of BD-2. This provides a protective effect on neonatal rats with NEC.</p>

Animals , Bifidobacterium , Disease Models, Animal , Enterocolitis, Necrotizing , Therapeutics , Humans , Infant, Newborn , Intestinal Mucosa , Metabolism , NF-kappa B , Physiology , Rats , Rats, Sprague-Dawley , Signal Transduction , Physiology , beta-Defensins , Genetics , Physiology
Arq. bras. oftalmol ; 80(5): 277-280, Sept.-Oct. 2017. tab, graf
Article in English | LILACS | ID: biblio-888148


ABSTRACT Purpose: To investigate human beta-defensins (HBDs) and cathelicidin LL-37 (LL-37) expressions in patients with pterygium. Methods: In this retrospective consecutive case series, 26 pterygium specimens and 15 normal conjunctival specimens of 15 control subjects were in vestigated. Expressions of HBD-1, HBD-2, HBD-3, and LL-37 were assessed using immuno histochemical staining. A brown color in the cytoplasm and/or nuclei of epithelial cells indicated positive staining for HBDs and LL-37. For each antibody, the intensity of the reaction (negative [-], weak [1+], moderate [2+], or strong [3+]) was determined to describe the immunoreactions. Results: The median age was 52 years in both groups. There were no significant differences in age and sex between the groups (p=0.583, p=0.355, respectively). Of the 26 pterygium specimens, 15 (57.7%) (14 weak, 1 moderate staining) showed HBD-2 expression, which was not observed in any of the control specimens. One (3.8%) pterygium and one (6.7%) control specimen demonstrated weak staining for HBD-3. HBD-2 expression was significantly higher in the pterygium specimens than in the controls (p=0.002). None of the tissue specimens had positive staining for HBD-1 or LL-37 in either group (both; p=1.00). Conclusions: HBD-2 expression was higher in pterygium specimens than in the controls. HBD-2 expression that might be stimulated by inflammatory cytokines may be related to inflammation and fibrovascular proliferation and may play a role in pterygium pathogenesis.

RESUMO Objetivo: Investigar as expressões beta defensinas humanas (HBD) e catelicidina em pacientes com pterígio. Métodos: Nesta série de casos retrospectivos consecutivos, 26 espécimes de pterígio e 15 espécimes conjuntivais normais de 15 indivíduos controle foram investigados. As expressões de HBD-1, HBD-2, HBD-3 e catelicidina (LL-37) foram avaliadas por coloração imuno-histoquímica. Uma cor castanha no citoplasma ou nos núcleos de células epiteliais foi definida como coloração positiva para HBDs e LL-37. Para cada anticorpo foi determinada a intensidade da reação (negativo [-], fraco [1+], moderado [2+] ou forte [3+]) para descrever as imunoreações. Resultados: A idade média foi de 52 anos em ambos os grupos. Não houve diferença significativa entre os grupos em termos de idade e sexo (p=0,583, p=0,355, respectivamente). Das 26 amostras de pterígio, 15 (57,7%) (14 fracas e 1 moderada) demonstraram a expressão de HBD-2 enquanto não foi encontrada em nenhum dos espécimes de controlo. Um dos pterígios (3,8%) e um dos espécimes de controlo (6,7%) demonstraram fraca coloração para HBD-3. A expressão de HBD-2 foi significati vamente maior nos espécimes de pterígio do que nos controles (p=0,002). Nenhum dos espécimes de tecido apresentou coloração positiva para HBD-1 ou LL-37 em ambos os grupos (ambos p=1,00). Conclusão: Encontramos aumento da expressão de HBD-2 em espécimes de pte rígio em relação aos controles. A expressão de HBD-2 que pode ser estimulada por citocinas inflamatórias pode estar relacionada com inflamação e proliferação fibrovascular e pode desempenhar um papel na patogênese do pterígio.

Humans , Male , Female , Adult , Middle Aged , Aged , Pterygium/metabolism , Antimicrobial Cationic Peptides/analysis , beta-Defensins/analysis , Reference Values , Biopsy , Immunohistochemistry , Case-Control Studies , Retrospective Studies , Statistics, Nonparametric , Conjunctiva/chemistry
Braz. j. microbiol ; 47(2): 389-393, Apr.-June 2016. tab
Article in English | LILACS | ID: lil-780843


Abstract β-Defensin-1, an antimicrobial peptide encoded by the DEFB1 gene, is known to play an important role in lung mucosal immunity. In our association study we analyzed three DEFB1 functional polymorphisms -52G>A (rs1799946), -44C>G (rs1800972) and -20G>A (rs11362) in 92 tuberculosis patients and 286 healthy controls, both from Northeast Brazil: no association was found between the studied DEFB1 polymorphisms and the disease. However we cannot exclude that this lack of association could be due to the low number of subjects analyzed, as suggested by the low statistical power achieved for the three analyzed SNPs (values between 0.16 and 0.50).

Humans , Male , Female , Adult , Middle Aged , Aged , Young Adult , Tuberculosis/genetics , Polymorphism, Single Nucleotide , beta-Defensins/genetics , Tuberculosis/epidemiology , Haplotypes , Brazil/epidemiology , Molecular Sequence Data , Base Sequence , Genetic Predisposition to Disease , Genotype
Chinese Medical Journal ; (24): 696-701, 2016.
Article in English | WPRIM | ID: wpr-328172


<p><b>BACKGROUND</b>Antimicrobial peptides, including cathelicidin LL-37, human beta defensin (HBD)-2, and HBD-3, are important elements of the innate immune response and involved in modulation of the adaptive immunity, and they also play an important role in cutaneous defense against Mycobacterium tuberculosis.</p><p><b>METHODS</b>The fresh skin tissues and paraffin-embedded biopsy samples from three cutaneous tuberculosis, two tuberculids, and ten healthy individuals were collected. The expressions of LL-37, HBD-2, and HBD-3 mRNA in the lesions of three cutaneous tuberculosis and two tuberculids were detected by quantitative real-time polymerase chain reaction; the protein expressions were detected by immunohistochemistry and Western blotting methods.</p><p><b>RESULTS</b>The expressions of LL-37 mRNA and protein in the lesions of cutaneous tuberculosis and tuberculids were similar to that of normal skin. The expression of HBD-2 mRNA had an increasing trend in the lesions of cutaneous tuberculosis and tuberculids compared with that of normal skin; however, the expression of HBD-2 protein in the lesions of cutaneous tuberculosis had a decreasing trend compared with that of normal skin, and the expression of HBD-2 protein in the lesions of tuberculids was similar to that of normal skin. The expressions of HBD-3 mRNA and protein in lesions of cutaneous tuberculosis and tuberculids were similar to that of normal skin.</p><p><b>CONCLUSIONS</b>Our study indicated that the expression of HBD-2 and HBD-3 mRNA and protein in lesions of cutaneous tuberculosis may be not consistent with that of tuberculids. However, an inherent limitation of the present study was that the sample size was small, and the roles and regulation mechanisms of LL-37, HBD-2, and HBD-3 in cutaneous tuberculosis and tuberculids need to be further investigated.</p>

Adult , Aged , Antimicrobial Cationic Peptides , Genetics , Female , Humans , Male , Middle Aged , RNA, Messenger , Tuberculosis, Cutaneous , Metabolism , beta-Defensins , Genetics
J. pediatr. (Rio J.) ; 91(1): 36-43, Jan-Feb/2015. tab, graf
Article in English | LILACS | ID: lil-741581


OBJECTIVE: To describe the antimicrobial activity of ß-defensin-2 produced in the mammary gland and secreted in human breast milk. METHODS: The peptide production was performed by DNA cloning. ß-defensin-2 levels were quantified in 61 colostrum samples and 39 mature milk samples from healthy donors, by an indirect enzyme-linked immunosorbent assay (ELISA). Using halo inhibition assay, this study assessed activity against seven clinical isolates from diarrheal feces of children between 0 and 2 years of age. The activity of ß-defensin-2 against three opportunistic pathogens that can cause nosocomial infections was determined by microdilution test. RESULTS: The peptide levels were higher in colostrum (n = 61) than in mature milk samples (n = 39), as follows: median and range, 8.52 (2.6-16.3) µg/ml versus 0.97 (0.22-3.78), p < 0.0001; Mann-Whitney test. The recombinant peptide obtained showed high antimicrobial activity against a broad range of pathogenic bacteria. Its antibacterial activity was demonstrated in a disk containing between 1-4 µg, which produced inhibition zones ranging from 18 to 30 mm against three isolates of Salmonella spp. and four of E. coli. ß-defensin-2 showed minimum inhibitory concentrations (MICs) of 0.25 µg/mL and 0.5 µg/mL for S. marcescen and P. aeruginosa, respectively, while a higher MIC (4 µg/mL) was obtained against an isolated of multidrug-resistant strain of A. baumannii. CONCLUSIONS: To the authors' knowledge, this study is the first to report ß-defensin-2 levels in Latin American women. The production and the activity of ß-defensin-2 in breast milk prove its importance as a defense molecule for intestinal health in pediatric patients. .

OBJETIVO: Descrever a atividade antimicrobiana da defensina-beta 2 na glândula mamária e secretada no leite materno humano. MÉTODOS: A produção de peptídeos foi realizada por clonagem de DNA. Os níveis de defensina-beta 2 foram quantificados em 61 amostras de colostro e 39 de leite maduro de doadoras saudáveis pelo teste ELISA indireto. Por um ensaio de halo de inibição, avaliamos a atividade contra sete isolados clínicos diarreicos de crianças entre 0 e 2 anos. A atividade da defensina 2 contra três patógenos oportunistas que podem causar infecções nosocomiais foi determinada pelo teste de microdiluição. RESULTADOS: Os níveis de peptídeos estavam significativamente maiores nas amostras de colostro (n = 61) que de leite maduro (n = 39), como segue: 8,52 (2,6-16,3 µg/mL) mediana e faixa em comparação a 0,97 (0,22-3,78), p < 0,0001; teste de Mann-Whitney. O peptídeo recombinante foi obtido da alta atividade antimicrobiana demonstrada contra uma ampla gama de bactérias patogênicas. Sua atividade antibacteriana foi demonstrada em um disco contendo entre 1-4 µg, que produziu zonas de inibição entre 18 e 30 mm contra três isolados de Salmonella spp. e quatro de E. coli. A defensina-beta 2 demonstrou concentrações inibitórias mínimas (CIMs) de 0,25 µg/mL e 0,5 µg/mL para S. marcescen and P. aeruginosa, ao passo que uma CIM maior (4 µg/mL) foi obtida contra um isolado de cepa multirresistente de A. baumannii. CONCLUSÕES: Até onde sabemos, este estudo é o primeiro a relatar níveis de defensina em mulheres da América Latina. A produção e a atividade da defensina 2 no leite materno comprovam sua importância como uma molécula de defesa para a saúde intestinal em pacientes pediátricos. .

Adult , Female , Humans , Pregnancy , Young Adult , Colostrum/chemistry , Milk, Human/chemistry , beta-Defensins/pharmacology , Enzyme-Linked Immunosorbent Assay/methods , Escherichia coli/drug effects , Lactation/immunology , Microbial Sensitivity Tests , Reverse Transcriptase Polymerase Chain Reaction/methods , Salmonella/drug effects , beta-Defensins/analysis
Biol. Res ; 48: 1-9, 2015. ilus, graf, tab
Article in English | LILACS | ID: biblio-950825


BACKGROUND: Recently, a continuous growth of interest has been observed in antimicrobial peptides (AMPs) in the light of an alarming increase in resistance of bacteria and fungi against antibiotics. AMPs are used as biomarkers in diagnosis and monitoring of oral cavity pathologies. Therefore, the determination of specific protein profiles in children diagnosed with early childhood caries (ECC) might be a basis for effective screening tests and specialized examinations which may enable progression of disease. METHODS: The objective of the studies was to determine the role of histatin-5 and ß-defensing-2 as a diagnostic marker of early childhood caries progression. In this work, results of concentration determination of two salivary proteins (histatin-5 and ß-defensin-2) were presented. In addition, bacterial profiles from dental plaque in various stages of ECC and control were marked. The assessment of alteration in the concentration of these two proteins in a study group of children with various stages of ECC and a control group consisting of children with no symptoms was performed by enzyme-linked immunosorbent assays. RESULTS: The statistical analysis showed a significant increase in the concentration of histatin-5 and ß-defensin-2 in the study group compared to the control group and correlated with the progression of the disease. CONCLUSIONS: The confirmation of concentration changes in these proteins during the progression of dental caries may discover valuable disease progression biomarkers.

Humans , Male , Female , Child, Preschool , Child , Saliva/chemistry , beta-Defensins/analysis , Dental Caries/diagnosis , Histatins/analysis , Streptococcus/classification , Streptococcus/growth & development , Enzyme-Linked Immunosorbent Assay , Biomarkers/analysis , Colony Count, Microbial , Signal Transduction , Linear Models , Bacterial Typing Techniques , Disease Progression , Dental Caries/microbiology , Dental Caries Susceptibility , Early Diagnosis , Lactobacillus rhamnosus/growth & development , Anti-Infective Agents/analysis
SQUMJ-Sultan Qaboos University Medical Journal. 2015; 15 (4): 440-444
in English | IMEMR | ID: emr-173877


Objectives: Behcet's disease [BD] is an immune-mediated small vessel systemic vasculitis. Human beta-defensins are antimicrobial peptides associated with many inflammatory diseases and are encoded by the beta-defensin family of multiple-copy genes. However, their role in BD necessitates further investigation. The aim of the present study was to investigate the possible association of BD in its various clinical forms with defensin beta-4 [DEFB4] genomic copy numbers

Methods: This case-control study was conducted from January to September 2011 and included 50 control subjects and 27 unrelated Iraqi BD patients registered at Baghdad Teaching Hospital, Bagdad, Iraq. Copy numbers of the DEFB4 gene were determined using the comparative cycle threshold method by duplex real-time polymerase chain reaction technology at the Department of Dermatology of Jena University Hospital, Jena, Germany

Results: DEFB4 genomic copy numbers were significantly higher in the BD group compared to the control group [P = 0.010]. However, no statistically significant association was found between copy numbers and clinical variables within the BD group

Conclusion: The DEFB4 copy number polymorphism may be associated with BD; however, it is not associated with different clinical manifestations of the disease

Humans , Male , Female , Adult , Middle Aged , beta-Defensins , Genomics , Gene Dosage , Case-Control Studies , Polymorphism, Genetic
Gut and Liver ; : 370-380, 2015.
Article in English | WPRIM | ID: wpr-203889


BACKGROUND/AIMS: This study investigated the expression of T cell immunoglobulin- and mucin-domain-containing molecule 3 (TIM-3), human beta-defensin (HBD)-2, forkhead box protein 3 (FOXP3), and the frequency of CD4+ CD25+ FOXP3+ regulatory T cells (Tregs) in children with Crohn's disease (CD) during infliximab therapy. METHODS: We enrolled 20 CD patients who received infliximab treatment for 1 year. Peripheral blood and colonic mucosal specimens were collected from all CD patients and from healthy control individuals. RESULTS: A significant difference in TIM-3 mRNA expression was evident in peripheral blood mononuclear cells and colonic mucosa between CD patients before infliximab therapy and the healthy controls (p<0.001 and p=0.005, respectively). A significant difference in HBD-2 mRNA expression was found in colonic mucosa between CD patients before infliximab therapy and the healthy controls (p=0.013). In the active phase of CD, at baseline, the median percentage of T cells that were CD25+ FOXP3+ was 1.5% (range, 0.32% to 3.49%), which increased after inflixmab treatment for 1 year to 2.2% (range, 0.54% to 5.02%) (p=0.008). CONCLUSIONS: Our study suggests that both the adaptive and innate immune systems are closely linked to each other in CD pathogenesis. And the results of our study indicate that it could be a useful therapeutic tool, where restoration of TIM-3, HBD-2 and the function of Tregs may repair the dysfunctional immunoregulation in CD.

Adolescent , Case-Control Studies , Colon/immunology , Crohn Disease/drug therapy , Female , Forkhead Transcription Factors/metabolism , Gastrointestinal Agents/therapeutic use , Humans , Infliximab/therapeutic use , Intestinal Mucosa/immunology , Leukocytes, Mononuclear/metabolism , Male , Membrane Proteins/metabolism , T-Lymphocytes, Regulatory/immunology , beta-Defensins/metabolism
Mem. Inst. Oswaldo Cruz ; 109(7): 918-922, 11/2014. tab, graf
Article in English | LILACS | ID: lil-728814


The human beta defensin 1 (hBD-1) antimicrobial peptide is a member of the innate immune system known to act in the first line of defence against microorganisms, including viruses such as human papillomavirus (HPV). In this study, five functional polymorphisms (namely g-52G>A, g-44C>G and g-20G>A in the 5’UTR and c.*5G>A and c.*87A>G in the 3’UTR) in the DEFB1 gene encoding for hBD-1 were analysed to investigate the possible involvement of these genetic variants in susceptibility to HPV infection and in the development of HPV-associated lesions in a population of Brazilian women. The DEFB1 g-52G>A and c.*5G>A single-nucleotide polymorphisms (SNPs) and the GCAAA haplotype showed associations with HPV-negative status; in particular, the c.*5G>A SNP was significantly associated after multiple test corrections. These findings suggest a possible role for the constitutively expressed beta defensin-1 peptide as a natural defence against HPV in the genital tract mucosa.

Adolescent , Adult , Aged , Female , Humans , Middle Aged , Young Adult , Papillomavirus Infections/genetics , Polymorphism, Single Nucleotide/genetics , Reproductive Tract Infections/virology , beta-Defensins/genetics , Brazil/epidemiology , Case-Control Studies , Genetic Predisposition to Disease , Haplotypes/genetics , Papillomavirus Infections/epidemiology