Fig. 5: INSRTR regulation of CAR T cell activation.
a Scheme of INSRTR-regulated CAR T receptor. P7 CC segment was inserted into a heavy chain of scFv at a loop neighboring CDR loops. b Antibody binding domain scFv CD19 N195 P7 in a CAR T receptor on cells activated by CD19-expressing Raji B cells. c Improved design of INSRTR CAR T receptor. An additional CC segment was fused to the N-terminus of the N195 P7 scFv(CD19) and a fusion peptide N5-P8A was used as a regulator. d Cells expressing N5_scFv(CD19)_N195_P7 were stimulated with Raji cells expressing CD19 antigen. e Antibody binding domain scFv Her2 S199 P7 in a CAR T receptor on cells activated by ErbB2-expressing SK-BR-3 cells. Statistical significance was tested with one-way ANOVA with Dunnett’s multiple comparisons test between the INSRTR variant and the addition of a REG peptide; P values 0.1234 (ns), 0.0332 (*), 0.0021 (**), 0.0002 (***), < 0.0001 (****) (significance, confidence intervals, degrees of freedom, F and P values are listed in Supplementary Table S2).
