Fig. 2
From: Tumor-associated myeloid cells in cancer immunotherapy
The origin of non-classical TAMCs. BM, spleen and embryo are the main sites of TAMCs differentiation, and the local tumor is the functional site of TAMCs. (1) TRMs constitute embryo-derived TAM. TRMs are derived from EMPs, which form in the yolk sac during embryogenesis. (2) Tumors induce splenic EMH, generating splenic MDSC & TAM (sMDSC, sTAM). (3) CD45+ EPCs accumulate in spleen. The red blood cell differentiation pathway of CD45+ EPC is blocked by tumors, thus it trans-differentiates into EDMC. (4) Pre-B doesn’t differentiate into B cell, but migrates from BM to the spleen and eventually trans-differentiates into B-MF in the tumor microenvironment