Figure EV1. Titration analysis of the LAT‐independent CAR microcluster formation.

WT or LAT‐deficient (J.LAT) Jurkat T cells expressing CAR‐GFP were stimulated on SLB coated with CD19 of indicated concentrations. The clustering of Alexa Fluor 647‐labeled streptavidin in conjugation with biotin‐CD19 was imaged by TIRF microscopy and quantified as normalized variance in the same way as in Fig 3B. Shown are the means ± SD. n = 52, 38, and 44 cells for WT at 10, 2 and 0.4 nM, respectively, and 47, 38, and 44 cells for lat‐ cells at 10, 2 and 0.4 nM, respectively.