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Background Chimeric antigen receptor macrophages (CAR-M) represent a promising immunotherapy candidate for solid tumors, by combining targeted antigen recognition with innate immune functions. However, challenges such as donor variability, limited manufacturing consistency, and inefficient genetic modification, hinder their clinical applicability. Here, we describe a novel CAR construct designed to provide dual signaling. We have developed a reliable and reproducible platform to produce CAR-M from both induced pluripotent stem cells (iPSCs) and umbilical cord blood-derived CD34 + hematopoietic stem cells (CB-HSCs), offering a reproducible alternative cell source to monocyte-derived CAR-Ms.Methods CAR-M were generated from two renewable cell sources: iPSCs and CB-HSCs, each were transduced with a lentiviral vector encoding a second-generation anti-CEA CAR featuring unique intracellular signaling domains to maintain M1 phenotype and CAR-M phagocytic activity. Transduction efficiency was measured via GFP expression, and GFP + cells were sorted for downstream analysis. CB-HSCs were expanded and differentiated using a cytokine cocktail, while iPSCs underwent a stage-wise cytokine differentiation protocol. Anti-tumor efficacy was evaluated by quantifying phagocytosis and cytokine production in co-culture assays with CEA+ tumor cells labelled with pHrodo dye. Flow cytometry was used for phenotypic analysis over time.Results Lentiviral transduction efficiency achieved a maximum of 50%. Sorted GFP + cells retained stem/progenitor identity and demonstrated high viability of 97%, making them suitable for downstream differentiation. Despite different differentiation methods, CB-HSC-derived CAR-Ms yielded approximately 98% expression of CD45+CD14+CD11b+ markers. While preliminary data from iPSC-derived CAR-Ms indicate similar viability and myeloid marker expression. Functional assays demonstrated strong, antigen-specific phagocytosis of CEA+ tumor cells peaking at 6hrs, confirmed via live-cell imaging and quantified over 48hrs. Second generation CAR-Ms with dual intercellular signaling domains exhibited sustained tumor clearance, increased pro-inflammatory cytokine production, and an M1-like polarization profile via the expression of CD80 and CD86 over 7 days compared to wild-type macrophages.Conclusions Our findings demonstrate a reproducible and efficient method for generating functional CAR-M from renewable stem cell sources. Our initial data shows that the enhanced CAR construct increases macrophage activation, tumor targeting, and M1 polarization supporting the potential of this platform for standardized CAR-M manufacturing in solid tumor immunotherapy.