Detection of ADA. (A) Relative light unit (RLU) values of serial time points for all 18 patients in the screening assay. The four PD/relapse patients are shown in red, and others are in gray. The screening cut-point of RLU was derived by multiplying the median of negative control RLU values in each plate by the threshold factor 1.2, which was approximately 86.6, as shown in the dotted blue line. Four samples from 3 patients were putative positive and further validated in the confirmatory assay. (B) The relationship between ADA and CAR transgenes in patient 01-016. The left y-axis represented the viral copy number (VCN); the right y-axis represented the RLU.