Vgamma9Vdelta2 T cell-mediated recognition of human solid tumors. Potential for immunotherapy of hepatocellular and colorectal carcinomas.

Introduction: Vgamma9Vdelta2 T lymphocytes are reported to participate in the anti-tumor immune surveillance in human. They are known to recognize phosphoantigens and molecules expressed on cells undergoing neoplasic transformation. In this study, we investigated phenotype and anti-tumor cytotoxicity of ex vivo expanded Vgamma9Vdelta2 T cells in view of adoptive immunotherapy.

In vitro antitumor lymphocyte generation using dendritic cells and innate immunity mechanisms as tumor cell treatments.

Dendritic cells play a central role in the initiation and regulation of acquired and innate immunity, playing an important role in immunosurveillance and antitumor reaction. This reaction is mediated by effector cells and soluble factors. We chose to investigate four dendritic cell loading methods by mimicking innate immunity mechanisms and using whole tumor cell treatments in order to stimulate lymphocytes: sodium hypochlorite, TNFalpha and IFNgamma and IgG opsonization.

Ex vivo expansion of antitumor cytotoxic lymphocytes with tumor-associated antigen-loaded dendritic cells.

Cell therapy with lymphocytes is an attractive approach for cancer immunotherapy. Methods to generate ex vivo effector cells directed against whole autologous tumor antigens are under investigation. Our procedure involved stimulation of autologous lymphocytes with antigen-pulsed dendritic cells (DC).

Dendritic cells are defective in breast cancer patients: a potential role for polyamine in this immunodeficiency.

Introduction: Dendritic cells (DCs) are antigen-presenting cells that are currently employed in cancer clinical trials. However, it is not clear whether their ability to induce tumour-specific immune responses when they are isolated from cancer patients is reduced relative to their ability in vivo. We determined the phenotype and functional activity of DCs from cancer patients and investigated the effect of putrescine, a polyamine molecule that is released in large amounts by cancer cells and has been implicated in metastatic invasion, on DCs.

Constitutive expression of TGF-bêta1, interleukin-6 and interleukin-8 by tumor cells as a major component of immune escape in human ovarian carcinoma.

Tumors could use several mechanisms to coexist with the host's immune system or to protect themselves from an immune response. Thus, insufficient expression of cell surface molecules on tumor cells, which are important for T cell recognition or activation, could lead to induction of a state of tolerance. Tumor cells could also produce cytokines that would inhibit the immune response and allow tumor progression.

Cytotoxic effector cells with antitumor activity can be amplified ex vivo from biopsies or blood of patients with renal cell carcinoma for cell therapy use.

Adoptive immunotherapy with antitumor effector cells is an attractive therapeutic approach in metastatic renal cell carcinoma (RCC). The aim of the work was to enhance in vitro activation of lymphocytes with optimal cytotoxic activity against tumor cells. We evaluated a procedure based on the use of dendritic cells (DCs) loaded with irradiated tumor cells (DC-Tu) to stimulate lymphocytes.

[Antitumor immunity and cellular cancer therapies].

The identification of tumor specific antigens has provided important advance in tumor immunology. It is now established that specific cytotoxic T lymphocytes (CTL) and natural killer cells infiltrate tumor tissues and are effector cells able to control tumor growth. However, such a natural antitumor immunity has limited effects in cancer patients.