FITC-tagged IL-3R α/CD123 is a cell surface receptor for IL3 expressed on hematopoietic progenitor cells, monocytes, and B lymphocytes, regulating their production and differentiation. IL-3R alpha/CD123 Protein, Human (HEK293, His) is the recombinant human-derived IL-3R alpha/CD123 protein, expressed by HEK293 , with C-6*His labeled tag.