No statistically significant difference was seen in TSG-6 levels between BPD mice and BPD mice injected with vehicle PBS, thus suggesting that the increase in TSG-6 expression in BPD or PBS-injected BPD mice may be associated with inflammatory response for protection against hyperoxia-induced lung injury (Additional file 1: Figure S10B). Here, TNFAIP6 is linked to bronchopulmonary dysplasia.