Corrigendum: Previous Radiotherapy Increases the Efficacy of IL-2 in Malignant Pleural Effusion: Potential Evidence of a Radio-Memory Effect? - Chen, Dawei; Song, Xinyu; Wang, Haiyong; Gao, Zhenwu; Meng, Wenjuan; Chen, Shuquan; Ma, Yunfeng; Wang, Youda; Li, Kong; Yu, Jinming; Yue, Jinbo (Frontiers in Immunology, 2021)