160 Background: To identify HLA-A0201 restricted epitope of novel cancer/testis antigen VCX/Y, generate antigen specific T cells and T-cell receptor (TCR) engineered T cells for adoptive cell therapy (ACT) of solid cancer patients. Methods: Reverse-immunology method was used to identify HLA-A0201 restricted epitope of VCX/Y. The high binding score peptide or whole length of VCX3A mRNA were pulsed or transfected to mature dendritic cells (mDC) from HLA-A0201+ donor and then stimulated autologous naïve T cells. Tetramer guided sorting were performed to purify the epitope specific T cells and CTL clones were generated with limiting dilution. TCR were cloned out from high activity CTL clone and the recombinant of retrovirus vector were constructed to introduce the TCR to allogeneic PBMC to generate the TCR engineered T cells. Results: One peptide which its sequence was shared with all VCX/Y members was identified. Interesting, only CTL clone generated from simulation of VCX3A mRNA transfected DC can recognize naturally processed VCX/Y presented by HLA-A0201+ tumor cells. Cold target inhibition detection confirmed that this VCX/Y peptide was naturally processed and recognized by HLA-A0201+ CTL clone. After infection of retrovirus containing the TCR from high activity of CTL clone, the TCR engineered T cells can recognize HLA-A2+ tumor cells but not normal lung cells. Moreover, these TCR engineered T cells specifically secreted IFN-γ in response to T2 cells pulsed with peptide, as well as HLA-A0201+ and VCX/Y overexpressed tumor cells. Conclusions: VCX/Y peptide we identified is a novel candidate peptide antigen for vaccine or for endogenous adoptive T cell therapy. The correlated high activity TCR gene can generate TCR engineered T cells from patients with anti-tumor activity and offer an alternative adoptive T cell treatment for patients with VCX/Y expressing solid tumor malignancies.
Antigen/major histocompatibility complex-specific activation of murine T cells transfected with functionally rearranged T-cell receptor genes.