β-defensin-2 in breast milk displays a broad antimicrobial activity against pathogenic bacteria
Journal Title: Jornal de Pediatria - Year 2015, Vol 91, Issue 1
Abstract
Objective To describe the antimicrobial activity of β-defensin-2 produced in the mammary gland and secreted in human breast milk. Methods The peptide production was performed by DNA cloning. β-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 β-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 1–4μg, which produced inhibition zones ranging from 18 to 30mm against three isolates of Salmonella spp. and four of E. coli. β-defensin-2 showed minimum inhibitory concentrations (MICs) of 0.25μg/mL and 0.5μg/mL for S. marcescen and P. aeruginosa, respectively, while a higher MIC (4μg/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 β-defensin-2 levels in Latin American women. The production and the activity of β-defensin-2 in breast milk prove its importance as a defense molecule for intestinal health in pediatric patients.
Authors and Affiliations
Luz Thomas
Behavioral and neural correlates of emotional development: typically developing infants and infants of depressed and/or anxious mothers
Objectives To describe the main findings of studies of behavioral and neural correlates regarding the development of facial emotion processing during the first year of life in typically developing infants and infants of...
Update on diagnosis and management of childhood epilepsies
Objectives To review the current evidence base for the diagnosis and management of the childhood epilepsies and to draw attention to the current gaps in this evidence base. The focus will be on therapeutic aspects. Curre...
Effects of programmed physical activity on body composition in post-pubertal schoolchildren
Objective To assess body composition modifications in post-pubertal schoolchildren after practice of a physical activity program during one school year. Methods The sample consisted of 386 students aged between 15 and 1...
Assessment of acute motor deficit in the pediatric emergency room
Objectives This review article aimed to present a clinical approach, emphasizing the diagnostic investigation, to children and adolescents who present in the emergency room with acute-onset muscle weakness. Sources A sy...
Sensitivity and specificity of different measures of adiposity to distinguish between low/high motor coordination
Objective This study aimed to determine the ability of different measures of adiposity to discriminate between low/high motor coordination and to evaluate the relationship between different measures of adiposity and moto...