FIG. 1.

Cytotoxicity of CTLs transfected with anti-CD19 CIR mRNA against CD19⁺ tumor cells. (A) Structure of anti-CD19 CIR, which contains a signal peptide, V_L and V_H domains of single-chain anti-CD19 antibody, a transmembrane (TM) domain, and signal transduction domains originated from 4-1BB and CD3 ζ proteins. (B) Cytotoxicity of mRNA-transfected CTLs against target cells loaded with ⁵¹Cr. The vertical axis represents normalized chromium release, and the horizontal axis indicates the effector-to-target (E:T) ratio. CTLs, after the standard 7 days of activation, were electroporated with CIR mRNA or without mRNA (mock ). K562 cells were used as a CD19-negative control. All other target cells expressed CD19 protein.