Human effector T cells derived from central memory cells rather than CD8+T cells modified by tumor-specific TCR gene transfer possess superior traits for adoptive immunotherapy

• We isolated CD8+TCM from healthy donors.
• We than transferred TCM with the gene encoding TCRs specific for tumor antigen.
• TE derived from TCM exhibited improved survival and reacquired the TCM phenotype.
• TCR gene transfer effectively promoted the specific killing of TCM.
• TCM were more effective than CD8+T cells in effector function after gene transfer.

Adoptive cell therapy provides an attractive treatment of cancer, and our expanding capacity to target tumor antigens is driven by genetically engineered human T lymphocytes that express genes encoding tumor-specific T cell receptors (TCRs). The intrinsic properties of cultured T cells used for therapy were reported to have tremendous influences on their persistence and antitumor efficacy in vivo. In this study, we isolated CD8+ central memory T cells from peripheral blood lymphocytes of healthy donors, and then transferred with the gene encoding TCR specific for tumor antigen using recombinant adenovirus vector Ad5F35-TRAV-TRBV. We found effector T cells derived from central memory T cells improved cell viability, maintained certain level of CD62L expression, and reacquired the CD62L+CD44high phenotype of central memory T cells after effector T cells differentiation. We then compared the antitumor reactivity of central memory T cells and CD8+T cells after TCR gene transferred. The results indicated that tumor-specific TCR gene being transferred to central memory T cells effectively increased the specific killing of antigen positive tumor cells and the expression of cytolytic granule protein. Furthermore, TCR gene transferred central memory T cells were more effective than TCR gene transferred CD8+T cells in CTL activity and effector cytokine secretion. These results implicated that isolating central memory T cells rather than CD8+T cells for insertion of gene encoding tumor-specific TCR may provide a superior tumor-reactive T cell population for adoptive transfer.