ADA enzyme activity and vector detection in PBMCs of gene therapy patients.

(A-B) Units of cytoplasmic ADA enzyme activity (▪) and percentage of LASN vector–positive cells (○) detectable in patient circulating lymphocytes obtained prior to infusion during the treatment phase and at various time points after cell infusions ended. T-cell infusions for each patient are indicated by the inverted blue triangles. The infusion of CD34⁺ cells to patient 2 is indicated as an upright triangle.