CD33 and neuroblastoma: As shown in Figures S3A, B, we detected the significantly correlated expression of M2 TAMs marker genes (CD163, CD204, CD206) and M-MDSC marker genes (CD11B, CD14, CD33) in the high-risk neuroblastoma examined, suggesting that the various numbers of M2 TAMs and MDSCs are present in the high-risk neuroblastoma TME.