Abstract

 

The non-viral delivery of the gene into macrophages, known as hard-to-transfect cells, is a challenge. In this study, the microporation of a CpG-free and small-sized plasmid (pCGfd-GFP) showed high transfection efficiency, sustainable transgene expression, and good cell viability in the transfections of Raw 264.7 and primary bone marrow-derived macrophages. The non-viral method using the pCGfd vector encoding anti-EGFR single chain Fv fused with Fc (scFv-Fc) generated the macrophages secreting anti-EGFR scFv-Fc. These macrophages effectively phagocytized tumor cells expressing EGFR through the antibody-dependent mechanism, which was proved by experiments using EGFR-knockout tumor cells. Finally, peri-tumoral injections of anti-EGFR scFv-Fc-secreting macrophages were shown to inhibit tumor growth in the xenograft mouse model.