The FMS-like tyrosine kinase 3 (FLT3) also known as cluster of differentiation antigen 135 (CD135) or fetal liver kinase-2 (Flk2) is a class III receptor tyrosine kinase (RTK) that plays a key role in controlling survival, proliferation, and differentiation of hematopoietic cells and it widely expresses in acute lymphoblastic leukemia (ALL) and acute myeloid leukemia (AML). Mutations in FLT3 (both internal tandem duplications (ITD) and point mutations) are among the most common somatic mutations in AML patients and are associated with poor prognosis and outcome in those patients.
 
Studies showed that many cancer patients with point mutations in the tyrosine kinase domain of FLT3, typically at the activation loop (AL) residue D835 would acquire clinical resistance to FLT3 inhibitors like sorafenib, quizartinib, ponatinib and crenolanib.
 
Signosis has generated a series of FLT3 mutants including FLT3 D835Y stably expressing in Ba/F3 cell line that can be used for studying the molecular mechanism of resistance in these mutant cell lines or screen for a new compound. 
 
Application
The cell line can be used;
- for studying the molecular mechanism of resistance in cancer patients with FLT3 mutation.
- for screening antibodies or compounds against FLT3.
- for studying cancer-related pathways in AML.
- for studying immune system-related pathways.
- as a cellular marker for separation of hematopoietic cells.