Human tumor-specific T lymphocytes: Does function matter more than number?

Institute of Cellular Pathology, Université catholique de Louvain, Avenue Hippocrate 74, UCL 7459, B-1200 Brussels, Belgium.
Current Opinion in Immunology (Impact Factor: 7.48). 07/2005; 17(3):320-5. DOI: 10.1016/j.coi.2005.03.002
Source: PubMed


In recent years, several clinical trials have involved the vaccination of cancer patients with tumor-specific antigens that are recognized by T lymphocytes. Anti-vaccine T-cell responses in these patients have been monitored on the assumption that their magnitude would correlate with clinical efficacy. Although analysis of these data show that such a correlation is emerging, detailed analyses of the few patients who benefit clinically from the vaccinations suggest that the function of the anti-vaccine T cells might be more important than their number. Recent studies show that in cancer patients numerous tumor-specific T cells appear to be quiescent in the presence of the tumor. Understanding how an efficient vaccine interferes with this coexistence is one of the current challenges of cancer immunotherapy.

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Available from: Pierre G Coulie, Jul 11, 2014
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    • "The mechanisms underlying the suppressive effects of Tregs include inhibiting the activity of a variety of immune cells that are tumor specific such as CD4 and CD8 cells, B cells, NK cells, natural killer T cells (NKT), and DCs [19] [20] [21]. Both types of T cells, CD4 and CD8 cells, are considered key components against tumors [22] [23]. Further, NK cells destroy tumor cells that have reduced the expression of MHC class I but still express ligands for activating receptors of NK cells [24]. "
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    04/2011; 2011:269519. DOI:10.1155/2011/269519
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    • "Regulatory T cells and cancer T lymphocytes that recognize TAA have been identified in blood, lymph nodes and at the tumour site of patients with advanced cancer. Expansion of these anti-tumour T cells in vitro is used to establish tumourspecific T cell lines, which have the ability to destroy tumour cells both in vitro and in vivo (Coulie and Connerotte, 2005). However, spontaneous tumour regression is rare, and although many immunotherapeutic trials have shown their ability to enhance the number of anti-tumour T cells, this strategy does not always coincide with metastasis eradication (Escobar et al., 2005; Lo´pez et al., 2004; Nestle et al., 1998, 2005). "
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