Reconstruction of Emphysematous Lung Tissue Using Slowly Released Basic Fibroblast Growth Factor From Gelatin Microspheres

Abstract

Basic fibroblast growth factor (bFGF) has a variety of activities including regeneration and neovascularization. This study was an attempt to reconstruct emphysematous lung tissue employing slow release of bFGF. Twenty beagle dogs were randomly split into four groups: a) control group (n = 5), b) porcine pancreatic elastase (PPE)-induced emphysema group (n = 5), c) FGF-MS group [n = 5, a suspension of bFGF-incorporated gelatin microspheres (MS) was injected via the pulmonary artery of emphysema model animals], and d) MS group (n = 5, MS without bFGF were injected). Four weeks after injection, the treated lungs were observed histologically, and the mean linear intercept (Lm) was calculated in each group. Lm in the FGF-MS and MS groups was significantly smaller than that in the emphysema group (p < 0.0001), and the size of the dilated alveoli was similar to that in the control group. These changes were more evident in the FGF-MS group, where almost normal alveoli and dense microvascularization were observed around the small pulmonary arteries. Reconstruction of emphysematous lungs was achieved by intrapulmonary arterial administration of MS with or without bFGF. This method may allow trans-pulmonary arterial therapy for pulmonary emphysema.