ANXA1 and bronchopulmonary dysplasia: While the present studies were not designed to delineate the mechanism(s) by which neonatal hyperoxic exposure alters the abundance of Clara cell subpopulations within the lung and/or protein production by Clara cells, our findings suggest the need for follow-up studies to determine the specific roles of SCGB family proteins and ANXA1 in lung innate immune responses in BPD.