Optimized Ex Vivo Differentiation of CD103⁺ Dendritic Cells and High-Efficiency Retroviral Transduction of Mouse Bone Marrow HSCs

CD103+ conventional dendritic cells (cDC1s) are key drivers of antitumor immunity, but their scarcity and resistance to genetic manipulation make them difficult to study. We optimized a two-stage ex vivo culture system using key cytokines and growth factors to efficiently generate CD103+ cDC1-like cells from mouse bone marrow progenitors. These cells closely mimicked their in-vivo counterparts, displaying CD103 expression, robust cytokine production, and functional responses to immune stimulation. Additionally, we established a high-efficiency retroviral transduction method using ecotropic pseudotyped virus and retronectin-coated plates, significantly improving gene delivery into mouse hematopoietic stem cells. This integrated platform provides a powerful approach for dissecting CD103+ cDC1 biology and advancing dendritic cell-based immunotherapy research.