Mhc Class I-Restricted Mart-127-35 Specific Tcr Engineered Human Cd4+And Cd8+T Cells Exhibit Polyfunctional Properties

Proceedings: AACR 101st Annual Meeting 2010‐‐ Apr 17‐21, 2010; Washington, DC The “polyfunctional” property of antigen specific T cells has turned out to be an important element in successful host immune responses in AIDS and in malignancies. We have shown that human CD4+ CD25- T cells engineered to express MHC Class I-restricted MART-127-35 epitope specific TCR show cytolytic activity, secret Th1 type cytokines. We have now carried out an extended analysis of the functional dimension of MART-127-35 epitope specific TCR engineered CD4+ and CD8+ T cells. Freshly isolated circulating CD4+ and CD8+ T cells, transduced with MART-127-35 epitope specific DMF5 TCR containing retrovirus, were tested for proliferative, cytokine secretory and for cytolytic capacity (polyfunctionality analyzed with intracytoplasmic immunofluorescence staining for IL-2, IFN-γ, TNF-α, MIP-1β and CD107a using the SPICE software). The TCR engineered CD4+ T cells were also tested for their potential for “helping” cytolytic T cells response by CD8+ T cells in in vitro CTL generation cultures. The TCR-engineered CD4+ as well as CD8+ T cells were found to be polyfunctional. For example, they underwent multiple rounds of division following stimulation by peptide pulsed dendritic cells and by melanoma cells, synthesized multiple cytokines (IFN-γ, TNF-α, IL-2, MIP1s) and lysed target cells. The TCR engineered CD4+ T cells also amplified the CD8+ CTL burst size in vitro. Multiparametric analyses revealed that a single TCR-engineered CD4+ T cell could perform as many as five different functions. Nearly 100% MART-127-35 specific TCR expressing CD4+ as well as CD8+ T cells could be generated through retroviral vector-based transduction and one round of in vitro stimulation by the peptide pulsed DC. MHC class I-restricted tumor epitope specific TCR-transduced CD4+ T cells, therefore, could be useful in immunotherapeutic strategies for melanoma or other human malignancies. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1925.