title: Neurotrophin serum concentrations and polymorphisms of neurotrophins and their receptors in children with asthma.
abstract: BACKGROUND
  In the recent years numerous studies have analysed the effects of neurotrophins on allergic inflammation in airway diseases reporting increased neurotrophin levels locally in the airways as well as in serum of asthmatic patients. We aimed to investigate if levels of neurotrophins in serum of asthmatic children are influenced by the genotype of functional variants within genes encoding analysed neurotrophins and their specific receptors.
  
  
  METHODS
  In the study we included 98 children diagnosed with asthma. Genotyping of 9 polymorphisms located in neurotrophins genes and their receptors genes was done with use of TaqMan SNP genotyping assays or PCR-RFLP. The serum levels of four neurotrophins (BDNF, NGF, NTF3, NTF4) were analysed during exacerbation of asthma symptoms with use of DuoSet ELISA Development Kit (R&D).
  
  
  RESULTS
  The two patients with the genetic variant A/A of NTRK1 (rs6334) showed significantly higher NGF serum concentrations (113.4 and 218.1 pg/mL) as compared to the mean NGF serum concentrations in the total group of patients (34.8 pg/mL). We also observed a significant epistatic interactions between variants of NGF rs6330 and NTRK1 rs6334 that influenced NGF serum level (P = 0.0004). Analysis of four neurotrophins serum levels in relation to different genotypes of analysed neurotrophins genes showed no significant differences among analysed asthmatic children.
  
  
  CONCLUSIONS
  Our results suggest that, among analysed neurotrophins, NGF serum levels may be influenced by the genotype of NTRK1 gene individually as well as in the interaction with NGF functional genetic variant suggesting their involvement in allergic inflammation in asthma. Serum levels of the other neurotrophins do not seem to be affected by the variants in the analysed genes.
authors.affiliation: Laboratory of Molecular and Cell Biology, Department of Pediatric Pulmonology, Allergy and Clinical Immunology, IIIrd Department of Pediatrics, Poznan University of Medical Sciences, Poznan, Poland. alszczep@amp.edu.pl
authors.forename: Aleksandra
authors.initials: A
authors.lastname: Szczepankiewicz
authors.forename: Marta
authors.initials: M
authors.lastname: Rachel
authors.forename: Paulina
authors.initials: P
authors.lastname: Sobkowiak
authors.forename: Zdzisława
authors.initials: Z
authors.lastname: Kycler
authors.forename: Irena
authors.initials: I
authors.lastname: Wojsyk-Banaszak
authors.forename: Natalia
authors.initials: N
authors.lastname: Schöneich
authors.forename: Aleksandra
authors.initials: A
authors.lastname: Szczawińska-Popłonyk
authors.forename: Anna
authors.initials: A
authors.lastname: Bręborowicz
mesh_terms: D000293:Adolescent; D001249:Asthma / Q000097:blood / Q000235:genetics* / Q000503:physiopathology; D002648:Child; D004843:Epistasis, Genetic; D005260:Female; D005541:Forced Expiratory Volume / Q000502:physiology; D005838:Genotype; D006801:Humans; D008297:Male; D020932:Nerve Growth Factor / Q000097:blood / Q000235:genetics; D009414:Nerve Growth Factors / Q000097:blood / Q000235:genetics*; D020641:Polymorphism, Single Nucleotide; D020917:Receptor, trkA / Q000235:genetics; D017475:Receptors, Nerve Growth Factor / Q000097:blood / Q000235:genetics*; D014797:Vital Capacity / Q000502:physiology
chemical_list: C502240:NGF protein, human; D009414:Nerve Growth Factors; D017475:Receptors, Nerve Growth Factor; D020932:Nerve Growth Factor; D020917:Receptor, trkA