CD123

CD123 is the α-subunit of the interleukin-3 receptor (IL-3α). The IL-3 receptor composed of it and IL-3β can promote the normal development and function maintaining of hematopoietic system and immune system after binding to ligands. Some research found that CD123 is one of the unique molecular markers of leukemia stem cells, which is expressed in acute myeloid leukemia (AML) and acute B-lymphoblastic leukemia (B-ALL), but has completely opposite mechanisms. Some scholars pointed out that AML with high CD123 expression has higher proliferative activity and anti-apoptotic ability, but its positivity is considered as a good prognostic factor for pediatric B-ALL patients. Moreover, the combination of CD123 with CD4, CD56, TCL1, and other antibodies plays a significant role in the diagnosis of blastic plasmacytoid dendritic cell neoplasm (BPDCN). Meanwhile, CD123 is strongly expressed in classical hairy cell leukemia (HCL-C) but not in variant HCL (HCL-V), which makes it useful for assisting in identification. In addition, CD123 can serve as an effective diagnostic biomarker for necrotic lymphadenitis.