This was consistent with reduced chemokinesis of PAH versus control neutrophils as assessed by confocal microscopic live-cell imaging of total distance moved in response to IL-8 stimulation (Figure 2C, Video 1) and longitudinal distance migrated across the fibronectin substrate (Figure 2D) and with formylmethionylleucylphenylalanine stimulation (Figure E2A), suggesting that impaired migration appeared to be independent of a specific receptor-activated pathway. Here, FN1 is linked to pulmonary arterial hypertension.