Respiratory strategy at birth initiates distinct lung injury phenotypes in the preterm lamb lung

ABSTRACT Bronchopulmonary disease is the chronic manifestation of the acute injury that may accompany ventilation following preterm birth. A lack of clear trial evidence often hampers clinical decision-making during support of the preterm lung at birth. Protein biomarkers have been used to define acute lung injury phenotypes and improve patient selection for specific interventions in adult respiratory distress syndrome. Here we present a mass spectrometry-based approach to profile the protein phenotype associated with three different aeration strategies known to cause different pathophysiological responses when applied at birth to preterm lambs. We were able to identify pathway enrichments specific to both ventilation strategy and lung regions based upon gravity-dependency. Ventilation strategy-specific phenotypes were further delineated by applying partial least square modelling to identify associations between specific proteins and clinical, physiological and morphological outcomes. This work highlights the specificity of lung injury responses to routinely applied birth interventions such as different respiratory support approaches and identified the molecular events associated with each. Furthermore, we demonstrate the capacity to subdivide preterm infants by the direct aetiology and response to lung injury; the first step towards true precision medicine in neonatology.