“…Furthermore, the residual mouse immune components, which mainly consist of macrophages and granulocytes may also interfere the responses. Efforts have been made to improve the human immune elements in the humanized mice, such as transgenically expression of different human growth factors and cytokines [112], [114], hydrodynamic tail vein injection of plasmid DNA encoding human cytokines [113], lentivirus or adeno-associated virus delivery of cytokines [115], [116], [117] and replacing the host genes with human counterparts [118], [119], [120]. Using genetically engineering technology, NSG-SGM3 mice (genetically engineered to produce IL-3, granulocyte/macrophage colony-stimulating factor (GM-CSF) and Steel factor (SF)), NSGW41 mice (KitW-41J allele), MISTRG (co-expressed M-CSF, IL-3, GM-CSF and thrombopoietin) and NSG-IL-15 (high expression of human IL-15) were established for improving the development and differentiation of HSCs, NKs and monocytes/macrophages [121], [122].…”