Abstract
ssCRE-BP/Purα is a single stranded DNA-binding protein and may be involved in gene replication and transcription and in the development of morphine dependence. We found a ssCRE-BP/Purα (45 kDa) in rat lung that was larger than those (40 kDa) identified in rat and mouse brains and mouse lung. Immunohistochemistry showed that ssCRE-BP/Purα is primarily distributed in the lung epithelium. As allergic inflammation induces various gene expressions, we investigated the changes of Purα during airway inflammation. Ovalbumin-sensitized rats were used for inducing allergic airway inflammation. The expression and DNA-binding activity of 45-kDa ssCRE-BP/Purα were significantly increased in the sensitized rat lungs 24 hr after antigen challenge, but not in those of rats nonsensitized or sensitized with ovalbumin and challenged with saline. Immunohistochemistry and in situ hybridization demonstrated that the vascular endothelial cells and numerous infiltrated eosinophils around the airways were stained with anti-Purα antibody. These data suggest that rat lung and the eosinophils contain a 45-kDa ssCRE-BP/Purα that is increased when airway inflammation occurs.
