Since the first reported clinical application of CD19-directed chimeric antigen receptor (CAR) T cell therapy for the treatment of B cell malignancies major advances have been made in CAR therapy.1 2 To date, four different CD19-directed CAR constructs, containing either a CD28 or 4-1BB co-stimulatory domain, have been Food and Drug Administration (FDA) and European Medicines Agency (EMA) approved to treat CD19+ hematological malignancies.3–6. Here, CD19 is linked to hematologic disorder.