Dataset Information

Abnormal pro-gly-pro pathway and airway neutrophilia in pediatric cystic fibrosis.

ABSTRACT: BACKGROUND:Proline-glycine-proline (PGP) is a bioactive fragment of collagen generated by the action of matrix metalloproteinase-9 (MMP-9) and prolylendopeptidase (PE), and capable of eliciting neutrophil chemotaxis and epithelial remodelling. PGP is normally then degraded by leukotriene A4 hydrolase (LTA4H) to limit inflammation and remodelling. This study hypothesized that early and persistent airway neutrophilia in Cystic Fibrosis (CF) may relate to abnormalities in the PGP pathway and sought to understand underlying mechanisms. METHODS:Broncho-alveolar lavage (BAL) fluid was obtained from 38 CF (9 newborns and 29 older children) and 24 non-CF children. BAL cell differentials and levels of PGP, MMP-9, PE and LTA4H were assessed. RESULTS:Whilst PGP was present in all but one of the older CF children tested, it was absent in non-CF controls and the vast majority of CF newborns. BAL levels of MMP-9 and PE were elevated in older children with CF relative to CF newborns and non-CF controls, correlating with airway neutrophilia and supportive of PGP generation. Furthermore, despite extracellular LTA4H commonly being greatly elevated concomitantly with inflammation to promote PGP degradation, this was not the case in CF children, potentially owing to degradation by neutrophil elastase. CONCLUSIONS:A striking imbalance between PGP-generating and -degrading enzymes enables PGP accumulation in CF children from early life and potentially supports airway neutrophilia.

SUBMITTER: Turnbull AR

PROVIDER: S-EPMC7001103 | biostudies-literature | 2020 Jan

REPOSITORIES: biostudies-literature

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Abnormal pro-gly-pro pathway and airway neutrophilia in pediatric cystic fibrosis.

Turnbull Andrew R AR Pyle Chloe J CJ Patel Dhiren F DF Jackson Patricia L PL Hilliard Tom N TN Regamey Nicolas N Tan Hui-Leng HL Brown Sarah S Thursfield Rebecca R Short Christopher C Mc Fie Megan M Alton Eric W F W EWFW Gaggar Amit A Blalock J Edwin JE Lloyd Clare M CM Bush Andrew A Davies Jane C JC Snelgrove Robert J RJ

Journal of cystic fibrosis : official journal of the European Cystic Fibrosis Society 20190605 1

<h4>Background</h4>Proline-glycine-proline (PGP) is a bioactive fragment of collagen generated by the action of matrix metalloproteinase-9 (MMP-9) and prolylendopeptidase (PE), and capable of eliciting neutrophil chemotaxis and epithelial remodelling. PGP is normally then degraded by leukotriene A<sub>4</sub> hydrolase (LTA<sub>4</sub>H) to limit inflammation and remodelling. This study hypothesized that early and persistent airway neutrophilia in Cystic Fibrosis (CF) may relate to abnormalities ...[more]

PMID: 31176670

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Dataset Information

Abnormal pro-gly-pro pathway and airway neutrophilia in pediatric cystic fibrosis.

Publications

Abnormal pro-gly-pro pathway and airway neutrophilia in pediatric cystic fibrosis.

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