Neutrophilic inflammation during lung development disrupts elastin assembly and predisposes adult mice to COPD

AUTHORS

Benjamin JT , Plosa EJ , Sucre JM , van der Meer R , Dave S , Gutor S , Nichols DS , Gulleman PM , Jetter CS , Han W , Xin M , Dinella PC , Catanzarite A , Kook S , Dolma K , Lal CV , Gaggar A , Blalock JE , Newcomb DC , Richmond BW , Kropski JA , Young LR , Guttentag SH , Blackwell TS , . The Journal of clinical investigation. ; 131(1).

PMID: 33108351 [PubMed].

ABSTRACT

Emerging evidence indicates that early life events can increase the risk for developing chronic obstructive pulmonary disease (COPD). Using an inducible transgenic mouse model for NF-κB activation in the airway epithelium, we found that a brief period of inflammation during the saccular stage (P3-P5) but not alveolar stage (P10-P12) of lung development disrupted elastic fiber assembly, resulting in permanent reduction in lung function and development of a COPD-like lung phenotype that progressed through 24 months of age. Neutrophil depletion prevented disruption of elastic fiber assembly and restored normal lung development. Mechanistic studies uncovered a role for neutrophil elastase (NE) in downregulating expression of critical elastic fiber assembly components, particularly fibulin-5 and elastin. Further, purified human NE and NE-containing exosomes from tracheal aspirates of premature infants with lung inflammation downregulated elastin and fibulin-5 expression by saccular-stage mouse lung fibroblasts. Together, our studies define a critical developmental window for assembling the elastin scaffold in the distal lung, which is required to support lung structure and function throughout the lifespan. Although neutrophils play a well-recognized role in COPD development in adults, neutrophilic inflammation may also contribute to early-life predisposition to COPD.

Tags: 2021