title: Cathelicidin and human β-defensin 2 in bronchoalveolar lavage fluid of children with pulmonary tuberculosis.
abstract: BACKGROUND
  The antimicrobial peptide cathelicidin LL-37/hCAP-18 and human β-defensins (hBD) are key factors in innate immune responses of the respiratory tract.
  
  
  OBJECTIVE
  To determine LL-37 and hBD-2 concentrations in the bronchoalveolar lavage (BAL) fluid of paediatric patients (aged <16 years) with pulmonary tuberculosis (TB) and to compare these with concentrations in healthy children.
  
  
  METHODS
  We measured peptide concentrations using an immunosorbent assay (ELISA). RESULTS Forty TB patients and 40 healthy controls were enrolled in the study (mean age 9.2 ± 4.7 and 8.3 ± 4.2 years, respectively, P = 0.97). The two groups exhibited no statistically significant difference in terms of sex, body mass index, relative weight or 25-hydroxyvitamin D levels. The mean BAL LL-37 level of the TB group was significantly higher than that of the control group (0.95 ± standard deviation [SD] 1.33 vs. 0.35 ± SD 0.51 ng/ml, P = 0.01, t = 2.54). The hBD-2 level was also higher in the TB group; however, the difference was not statistically significant (0.30 ± SD 0.58 vs. 0.14 ± SD 0.30 ng/ml, P = 0.11). There was no correlation between LL-37, hBD-2 and 25-hydroxyvitamin D levels. CONCLUSIONS Our data suggest that LL-37 and hBD-2 may play an important role in TB pathogenesis in children. To our knowledge, this is the first study on BAL LL-37 and hBD-2 concentrations in children with pulmonary TB.
authors.affiliation: Department of Paediatric Pulmonology, Bezmialem Vakif University Medical Faculty, Istanbul, Turkey.
authors.forename: E
authors.initials: E
authors.lastname: Cakir
authors.affiliation: Department of Paediatrics, Bezmialem Vakif University Medical Faculty, Istanbul, Turkey.
authors.forename: E
authors.initials: E
authors.lastname: Torun
authors.affiliation: Department of Paediatric Pulmonology, Bezmialem Vakif University Medical Faculty, Istanbul, Turkey.
authors.forename: A H
authors.initials: AH
authors.lastname: Gedik
authors.affiliation: Department of Anaesthesiology, Bezmialem Vakif University Medical Faculty, Istanbul, Turkey.
authors.forename: T
authors.initials: T
authors.lastname: Umutoglu
authors.affiliation: Department of Immunology, Institute of Experimental Medicine, Istanbul University, Istanbul, Turkey.
authors.forename: E C
authors.initials: EC
authors.lastname: Aktas
authors.affiliation: Department of Anaesthesiology, Bezmialem Vakif University Medical Faculty, Istanbul, Turkey.
authors.forename: U
authors.initials: U
authors.lastname: Topuz
authors.affiliation: Department of Immunology, Institute of Experimental Medicine, Istanbul University, Istanbul, Turkey.
authors.forename: G
authors.initials: G
authors.lastname: Deniz
mesh_terms: D000293:Adolescent; D000367:Age Factors; D023181:Antimicrobial Cationic Peptides; D015415:Biomarkers / Q000032:analysis; D001992:Bronchoalveolar Lavage Fluid / Q000737:chemistry* / Q000276:immunology / Q000382:microbiology; D016022:Case-Control Studies; D054804:Cathelicidins / Q000032:analysis*; D002648:Child; D002675:Child, Preschool; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D007113:Immunity, Innate; D007223:Infant; D008297:Male; D011237:Predictive Value of Tests; D014397:Tuberculosis, Pulmonary / Q000276:immunology / Q000378:metabolism* / Q000382:microbiology; D015854:Up-Regulation; D023083:beta-Defensins / Q000032:analysis*
chemical_list: D023181:Antimicrobial Cationic Peptides; D015415:Biomarkers; D054804:Cathelicidins; C106641:DEFB4A protein, human; D023083:beta-Defensins