MRC1 and neoplasm: Furthermore, > 1 kD molecules from S. aureus spent media increased the ratio of M1-like (anti-tumor phenotype, MHC-IIhigh, CD206−) to M2-like (pro-tumor phenotype, MHC-IIlow, CD206+) macrophages (M1/M2) (Supplementary Fig. 1C)23.