TY - JOUR T1 - G-CSF administration improves chronic lung disease caused by exposure to high-concentration oxygen in neonatal mice JF - European Respiratory Journal JO - Eur Respir J VL - 40 IS - Suppl 56 SP - P4131 AU - Isamu Hokuto AU - Takeshi Arimitsu AU - Yohei Matsuzaki AU - Kazushige Ikeda Y1 - 2012/09/01 UR - http://erj.ersjournals.com/content/40/Suppl_56/P4131.abstract N2 - Background: Chronic lung disease (CLD) is a condition that results from the inflammation-induced destruction and developmental arrest of the lungs of premature infants. To date, there is no effective treatment for CLD. Hematopoietic stem cells have been reported to differentiate into pulmonary type II epithelial cells. It is known that G-CSF acts on hematopoietic stem cells to mobilize them in the peripheral blood. It has also been reported that G-CSF exerts anti-inflammatory effects. In this study, we investigated wether G-CSF administration could improve a mouse model of CLD caused by exposure to high-concentration oxygen.Methods: Neonatal mice within 24 hours after birth were placed in 80% oxygen or room air for 21 days. From day 23, pups were administered 0.5 micro gram/g of G-CSF or saline for 5 days.The lungs were removed in postnatal week 6, and lung sections were stained with HE and Massons's trichrome and immunostained for PCNA and α-SMA for histology.Results: Compared with the control groups, the oxygen-exposed groups showed a significant emphysematous change. The oxygen-exposed, G-CSF administered group showed a significantly improvement in pulmonary emphysema than the oxygen-exposed, saline administered group. There were no significant differences in staining with Masson's trichrome nor immunostaining for PCNA and α-SMA.Discussion:G-CSF administration significantly improved a mouse model of CLD. It is unclear whether G-CSF-mobilized peripheral blood stem cells differentiated into pulmonary epithelial cells, whether G-CSF induced the proliferation and differentiation of type II epithelial cells, or whether G-CSF exerted anti-inflammatory effects. ER -