Temporal changes in expression of tgf-[beta] isoforms in mouse lung exposed to oxygen. O'reilly, Michael A., Rhonda J. Staversky, Kathleen C. Flanders, Carl J. Johnston, Jacob N. Finkelstein. Department of Pediatrics (Neonatology), Children's Hospital at Strong, University of Rochester, Rochester, NY 14642, Laboratory of Chemoprevention, Building 41, Rm C629, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
APStracts 3:0169L, 1996.
Oxygen-induced pulmonary injury is associated with cell death and a significant inflammatory response. Since transforming growth factor -[beta] is a potent modulator of the immune response, changes in expression of the three transforming growth factor-[beta] (TGF -[beta]1,-[beta]2,-[beta]3) isoforms was determined in lungs of adult mice exposed to >95% oxygen. TGF-[beta]1 immunostaining within cuboidal non-ciliated bronchiolar epithelial cells was increased within 3 hours of oxygen exposure and continued to increase for 48 hours before decreasing to control levels by 72 hours. A similar, but less marked change, was observed in granulated cells that were morphologically consistent with alveolar type II cells. Immunostaining for TGF-[beta]2 and TGF-[beta]3 revealed a similar change in bronchiolar epithelium with little change observed in the alveolar epithelium. Immunohistochemical changes in TGF-[beta] expression were not observed in any other pulmonary cells. Northern blot analysis of total lung RNA revealed that expression of the TGF- b mRNAs were not markedly altered over the 72 hour exposure period. Exposure to >95% oxygen resulted in cell-type specific post -transcriptional changes in TGF-[beta] isoforms in the lung.

Received 4 June 1996; accepted in final form 29 August 1996.
APS Manuscript Number L156-6.
Article publication pending Am. J. Physiol. (Lung Cell. Mol.
Physiology).
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 5 November 1996