CD40LG and chorioamnionitis: The BPD patients were divided into seven categories based on the existence or lack of respiratory distress syndrome (RDS), intrauterine infection/inflammation, including high umbilical cord blood immunoglobulin M (IgM) levels, chorioamnionitis, and funisitis, and diffuse bubbly/cystic appearances on chest X-rays (Supplementary Figure S1) [10,11].