Type I collagenases in bronchoalveolar lavage fluid from preterm babies atrisk of developing chronic lung disease

Objective-To assess whether increased collagenolysis precedes severe chroni c lung disease (CLD). Methods-Matrix metalloproteinase-1 (MMP-1) and MMP-8 (enzymes that degrade type I collagen, the main structural protein of lung extracellular matrix) were measured by enzyme linked immunosorbent assay in 100 bronchoalveolar l avage samples taken during the first 6 postnatal days fi om 45 ventilated p reterm babies <33 weeks gestation. The median value for each baby was calcu lated. CLD was defined as an oxygen requirement after the 36th week after c onception. Results-MMP-8 levels in bronchoalveolar lavage fluid were higher (median 13 ng/ml) in 20 babies who developed CLD than in 25 without CLD (median 2 ng/ ml). No MMP-1 was detected in any sample. Conclusions-MMP-8 can be detected in bronchoalveolar ravage fluid from pret erm babies, and higher levels are found in those who later develop CLD. MMP -8 may contribute to lung injury that occurs as a prelude to CLD.