T lymphocytes redirected to express κ light chain-specific CAR kill Igκ⁺ tumor cell lines. (A) Immunophenotype of tumor cell lines stained with CD19, anti-κ and anti-λ light-chain–specific antibodies. (B) Cytotoxic activity of T lymphocytes obtained from healthy donors and transduced either with control-GFP vector (□) or CAR46ζ (▦) or CAR46/28ζ (▪). Cytotoxic activity was evaluated in a standard ⁵¹Cr-release assay, and results are shown at an E/T ratio of 20:1. Data represent the mean ± SD of 6 different donors.