Bispecific T-cells expressing polyclonal repertoire of endogenous ?? T-cell receptors and introduced CD19-specific chimeric antigen receptor.

ABSTRACT: Even though other ?? T-cell subsets exhibit antitumor activity, adoptive transfer of ?? Tcells is currently limited to one subset (expressing V?9V?2 T-cell receptor (TCR)) due to dependence on aminobisphosphonates as the only clinically appealing reagent for propagating ?? T cells. Therefore, we developed an approach to propagate polyclonal ?? T cells and rendered them bispecific through expression of a CD19-specific chimeric antigen receptor (CAR). Peripheral blood mononuclear cells (PBMC) were electroporated with Sleeping Beauty (SB) transposon and transposase to enforce expression of CAR in multiple ?? T-cell subsets. CAR(+)?? T cells were expanded on CD19(+) artificial antigen-presenting cells (aAPC), which resulted in >10(9) CAR(+)?? T cells from <10(6) total cells. Digital multiplex assay detected TCR mRNA coding for V?1, V?2, and V?3 with V?2, V?7, V?8, V?9, and V?10 alleles. Polyclonal CAR(+)?? T cells were functional when TCR?? and CAR were stimulated and displayed enhanced killing of CD19(+) tumor cell lines compared with CAR(neg)?? T cells. CD19(+) leukemia xenografts in mice were reduced with CAR(+)?? T cells compared with control mice. Since CAR, SB, and aAPC have been adapted for human application, clinical trials can now focus on the therapeutic potential of polyclonal ?? T cells.

SUBMITTER: Deniger DC 

PROVIDER: S-EPMC3589159 | biostudies-literature | 2013 Mar

REPOSITORIES: biostudies-literature