Consequences of Cell Death: Exposure to Necrotic Tumor Cells, but Not Primary Tissue Cells or Apoptotic Cells, Induces the Maturation of Immunostimulatory Dendritic Cells (original) (raw)

2000, Journal of Experimental Medicine

Cell death by necrosis is typically associated with inflammation, in contrast to apoptosis. We have identified additional distinctions between the two types of death that occur at the level of dendritic cells (DCs) and which influence the induction of immunity. DCs must undergo changes termed maturation to act as potent antigen-presenting cells. Here, we investigated whether exposure to apoptotic or necrotic cells affected DC maturation. We found that immature DCs efficiently phagocytose a variety of apoptotic and necrotic tumor cells. However, only exposure to the latter induces maturation. The mature DCs express high levels of the DCrestricted markers CD83 and lysosome-associated membrane glycoprotein (DC-LAMP) and the costimulatory molecules CD40 and CD86. Furthermore, they develop into powerful stimulators of both CD4 ϩ and CD8 ϩ T cells. Cross-presentation of antigens to CD8 ϩ T cells occurs after uptake of apoptotic cells. We demonstrate here that optimal cross-presentation of antigens from tumor cells requires two steps: phagocytosis of apoptotic cells by immature DCs, which provides antigenic peptides for major histocompatibility complex class I and class II presentation, and a maturation signal that is delivered by exposure to necrotic tumor cells, their supernatants, or standard maturation stimuli, e.g., monocyte-conditioned medium. Thus, DCs are able to distinguish two types of tumor cell death, with necrosis providing a control that is critical for the initiation of immunity.

Efficient antitumor immunity derived from maturation of dendritic cells that had phagocytosed apoptotic/necrotic tumor cells

International Journal of Cancer, 2001

Dendritic cells (DCs) that acquired antigen from apoptotic tumor cells are able to induce major histocompatibility complex (MHC) class I-restricted cytotoxic T lymphocytes and antitumor immunity. In the present study, we investigated the efficiency of antitumor immunity derived from DCs that had phagocytosed apoptotic/necrotic BL6-10 melanoma cells compared with that of DCs pulsed with the tumor mTRP2 peptide. Our data showed that phagocytosis of apoptotic/necrotic tumor cells resulted in maturation of DCs with up-regulated expression of proinflammatory cytokines [interleukin (IL)-1β, IL-6, tumor necrosis factor-α, interferon-γ and granulocyte-macrophage colony-stimulating factor], chemokines (MIP-1α, MIP-1β and MIP-2), the CC chemokine receptor CCR7 and the cell surface molecules (MHC class II, CD11b, CD40 and CD86), and down-regulated expression of the CC chemokine receptors CCR2 and CCR5. These mature DCs displayed enhanced migration toward the CC chemokine MIP-3β in a chemotaxis assay in vitro and to the regional lymph nodes in an animal model in vivo. Our data also showed that vaccination with DCs that had phagocytosed apoptotic/necrotic BL6-10 cells was able to (i) more strongly stimulate allogeneic T-cell proliferation in vitro, (ii) induce an in vivo Th1-type immune response leading to more efficient tumor-specific cytotoxic CD8+ T-cell-mediated immunity and (iii) eradicate lung metastases in all 6 vaccinated mice compared with mice vaccinated with DCs pulsed with the tumor mTRP2 peptide, in which lung metastases were reduced (mean number of 16 per mouse) but not completely eradicated. Therefore, DCs that had phagocytosed apoptotic/necrotic tumor cells appear to offer new strategies in DC cancer vaccines. © 2001 Wiley-Liss, Inc.

Select forms of tumor cell apoptosis induce dendritic cell maturation

Journal of Leukocyte Biology, 2004

Dendritic cells (DC) play a crucial role in initiating immune responses to tumors. DC can efficiently present antigens from apoptotic tumor cells, but apoptotic cells are thought to lack the inflammatory signals required to induce DC maturation. Here, we show that apoptosis of 67NR mouse carcinoma cells via the Fas (CD95) pathway or induced by the anticancer drug bortezomib (PS-341) but not by ultraviolet irradiation is associated with the production of maturation signals for DC. These data have important implications for the effects of chemotherapy on antitumor immunity in solid and hematologic malignancies. J. Leukoc. Biol. 77: 000 -000; 2005.

Post-apoptotic tumors are more palatable to dendritic cells and enhance their antigen cross-presentation activity

Vaccine, 2008

Critical issues for cytotoxic lymphocyte (CTL) cross-priming are (a) the maturation state of dendritic cells (DC), (b) the source of the tumor-associated antigens (TAA) and (c) the context in which they are delivered to DCs. Drug-induced apoptosis has recently been implicated in CTL cross-priming. However, since drug-treatment produces in vivo more tumor cells than the DC default apoptotic clearance program can cope with, they are expected to proceed to secondary necrosis and change their molecular pattern.

Induction of Tumor Cell Apoptosis or Necrosis by Conditional Expression of Cell Death Proteins: Analysis of Cell Death Pathways and In Vitro Immune Stimulatory Potential

The Journal of Immunology, 2009

For the efficient stimulation of T cells by tumor Ag, tumor-derived material has to be presented by dendritic cells (DC). This very likely involves the uptake of dead tumor cells by DC. Cell death in tumors often occurs through apoptosis, but necrotic cell death may also be prevalent. This distinction is relevant because numerous studies have proposed that apoptotic cells have immunosuppressive effects while necrosis may be stimulatory. However, a system has been lacking that would allow the induction of apoptosis or necrosis without side effects by the death stimuli used experimentally. In this study, we present such a system and test its effects on immune cells in vitro. B16 mouse melanoma cells were generated and underwent cell death through the doxycyclineinducible induction of death proteins. In one cell line, the induction of Bim S induced rapid apoptosis, in the other line the induction of the FADD death domain induced nonapoptotic/necrotic cell death. Bim S-induced apoptosis was associated with the typical morphological and biochemical changes. FADD death domain induced necrosis occurred through a distinct pathway involving RIP1 and the loss of membrane integrity in the absence of apoptotic changes. Apoptotic and necrotic cells were taken up with comparable efficiency by DC. OVA expressed in cells dying by either apoptosis or necrosis was cross-presented to OT-1 T cells and induced their proliferation. These results argue that it is not the form of cell death but its circumstances that decide the question whether cell death leads to a productive T cell response.

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