• Fms-like tyrosine kinase receptor 3 (Flt3) is a membrane protein that is strongly expressed on hematopoietic stem cells (HSCs). FLT3LG (FLT3 ligand) is a growth factor that can stimulate the proliferation, differentiation, and survival of these cells when it binds to its receptor FLT3. The Flt3/Flt3L signaling axis indeed plays an important role in the production of conventional dendritic cells (cdc) and plasmacytoid dendritic cells (pDCs). Both types of dendritic cells are critical members of the immune system involved in processes such as fighting infections and regulating immune responses.
• Gene editing strategy: The exons 2-9 of mouse Flt3 gene are replaced by the reverse inserted exons 1-9 of human FLT3LG including promoter, 5’UTR and 3’UTR region in B-NDG hFLT3LG, Flt3 KO mice.
• Protein expression analysis: Human FLT3LG was detectable in heterozygous B-NDG hFLT3LG, Flt3 KO mice but not in B-NDG mice. 
• Application: This product results in a high level of immune system reconstitution after the transplantation of artificial hematopoietic stem cells, especially for DC cells.

Strain specific FLT3LG expression analysis in heterozygous B-NDG hFLT3LG, Flt3 KO mice by ELISA. Serum were isolated from B-NDG mice (+/+) and heterozygous B-NDG hFLT3LG, Flt3 KO mice (H/+) and analyzed by ELISA with species-specific FLT3LG ELISA kit (anti-mouse FLT3LG antibody: R&D, MFK00; anti-human FLT3LG antibody: R&D, DFK00). Mouse FLT3L was detectable in B-NDG mice and heterozygous B-NDG hFLT3LG, Flt3 KO mice. Human FLT3LG was exclusively detectable in heterozygous B-NDG hFLT3LG, Flt3 KO mice (Male, 8-week-old, n=2). Human blood was positive control. Values are expressed as mean ± SEM.