Abstract
Introduction: Bronchopulmonary dysplasia (BPD) or chronic lung injury of newborn is a life-threatening condition in preterm infants with few effective therapies. Mesenchymal stem cells (MSC) are a promising therapeutic strategy for BPD. The ideal MSC source for BPD prevention is however unknown. Umbilical cord tissue (UCT) MSC may potentially have more anti-inflammatory and pro-angiogenic properties. Hypothesis: We hypothesized that the UCT-MSC will have superior lung regenerative effect in BPD owing to superior anti-inflammatory and pro-angiogenic properties as compared to BM-MSC. Methods: Newborn rats (n=10-12/group) were randomly assigned to normoxia or hyperoxia (85% O 2 ) from postnatal day (P) 1 to 21 were given intra-tracheal (IT) BM or UCT-MSC (1 x 10 6 cells/50 μl), or placebo (PL) on P3. Results: Hyperoxia PL-treated pups had marked alveolar simplification, vascular rarefaction, remodeling and lung inflammation. Administration of both BM-MSC and UCT-MSC significantly improved alveolar structure, vascular density, pulmonary hypertension, vascular remodeling and lung inflammation. However, the improvement in alveolar structure and lung inflammation was more marked in hyperoxic pups who received UCT-MSC. In vitro studies demonstrated greater TSG-6 and IL-10 expression in UCT-MSC as compared to BM-MSC. Moreover, lung epithelial cells incubated with UCT-MSC conditioned media had greater wound healing following scratch injury. Conclusion: These findings demonstrate that while both BM and UCT-MSC have lung regenerative effects, UCT-MSC have greater anti-inflammatory and alveolar protective effects in experimental BPD. These findings have significant implications for cellular therapy in BPD, as it suggests that UCT-MSC are a superior cellular source for preterm lung protection.