PRENATAL EXPOSURE TO EPIDERMAL GROWTH-FACTOR ATTENUATES RESPIRATORY-DISTRESS SYNDROME IN RHESUS INFANTS

Treatment of nonhuman primate fetuses with epidermal growth factor (EG F) results in histologic and biochemical maturation of their lungs. To determine whether these effects improve lung function postnatally, we studied premature rhesus infants delivered at 78% of gestation after in utero treatment with EGF (n = 5) or placebo (n = 5). Indices of lun g function during the 4 d of postnatal care included fractional concen tration of inspired oxygen, peak inspiratory pressure, ventilator rate , mean airway pressure, arterial to alveolar oxygen tension ratio, and ventilation index. Statistically significant differences were noted i n the time courses of these variables between EGF- and placebo-treated infants. The direction of the differences indicated that the EGF-trea ted infants had less severe lung disease. Surfactant apoprotein A conc entration and lecithin to sphingomyelin ratio were both significantly higher in the amniotic fluid of the EGF-treated group, indicating adva nced biochemical maturation in this group of animals. Whereas birth we ight was not affected by EGF exposure, adrenal and gut weights, standa rdized for body weight, were increased significantly. Histologic studi es showed advanced cellular maturation with increased parenchymal airs pace and decreased parenchymal tissue space in the EGF-treated group c ompared with the control group. We conclude that prenatal exposure to EGF stimulates biochemical and histologic maturation of the lung and m arkedly attenuates the clinical severity of respiratory disease in thi s model of simian respiratory distress syndrome.