Thrombospondin-1 Plays a Major Pathogenic Role in Experimental and Human Bronchopulmonary Dysplasia

Extremely preterm infants develop bronchopulmonary dysplasia (BPD), a chronic lung injury that lacks effective treatment. TSP-1 (thrombospondin-1) is an antiangiogenic protein that activates TGF-β1 (transforming growth factor-β1), a cytokine strongly linked to both experimental and human BPD. The purpose of present study is 1) To examine effects of inhibiting TSP-1–mediated TGF-β1 activation (LSKL [leucine–serine–lysine–leucine]) in neonatal rats with bleomycin-induced lung injury; 2) to examine effects of a TSP-1 mimic (ABT-510) on lung morphology; and 3) to determine whether TSP-1 and related signaling peptides are increased in lungs of human preterm infants at risk for BPD.TSP-1 inhibits alveologenesis in neonatal rats, in part via the upregulated activity of TGF-β1. Observations in human lungs suggest a similar pathogenic role for TSP-1 in infants at risk for BPD.