BACKGROUND: Gene expression databases are key resources for microarray data management and analysis and the importance of a proper annotation of their content is well understood.Public repositories as well as microarray database systems that can be implemented by single laboratories exist. However, there is not yet a tool that can easily support a collaborative environment where different users with different rights of access to data can interact to define a common highly coherent content. The scope of the Genopolis database is to provide a resource that allows d...

Recently, new methods have been introduced describing assessment of antigen-specific CD4+ T-cell immunity according to the induction of CD154 (CD40L) on CD4+ T cells during short-term activation. In our study, we have evaluated the influence of different stimulation conditions on the flow cytometric analysis of CD154 expression after antigenic in vitro activation. We used different cell preparation methods, antigen sources, and time periods of in vitro stimulation and analyzed their impact on intra and extracellular detection of antigen-induced CD154 expression o...

Dendritic cells (DCs) link innate and adaptive immunity, initiating and regulating effector cell responses. They ubiquitously express members of the LILR (ILT, LIR, CD85) family of molecules, some of which recognize self-HLA molecules, but little is known of their possible functions in DC biology. We demonstrate that the inhibitory receptor LILRB1 (ILT2, LIR1, CD85j) is selectively up-regulated during DC differentiation from monocyte precursors in culture. Continuous ligation of LILRB1 modulated cellular differentiation, conferred a unique phenotype upon the result...

For the last four decades, the treatment of cancer has relied on four treatment modalities, namely surgery, radiotherapy, cytotoxic chemotherapy, and hormonotherapy. Most of these therapies are believed to directly attack and eradicate tumor cells. The emerging concept that cancer is not just a disease of a tissue or an organ but also a host disease relies on evidence of tumor-induced immunosuppression and polymorphisms in genes involved in host protection against tumors. This theory is now gaining new impetus, based on our recent data showing that optimal therape...

CD1d-restricted lymphocytes recognize a broad lipid range. However, how CD1d-restricted lymphocytes translate T cell receptor (TCR) recognition of lipids with similar group heads into distinct biological responses remains unclear. Using a soluble invariant NKT (iNKT) TCR and a newly engineered antibody specific for -galactosylceramide (-GalCer)–human CD1d (hCD1d) complexes, we measured the affinity of binding of iNKT TCR to hCD1d molecules loaded with a panel of -GalCer analogues and assessed the rate of dissociation of -GalCer and -GalCer analogues from hCD1d mo...

A unique subpopulation of spleen dendritic cells (DCs) that express the CD8 surface marker efficiently present phagocytosed antigens to CD8(+) T lymphocytes in a process called "crosspresentation," which initiates cytotoxic immune responses. We now show that the small GTPase Rac2 plays a critical role in antigen crosspresentation selectively in this DC subpopulation. In CD8(+) DCs, Rac2 determines the subcellular assembly of the NADPH oxidase complex (NOX2) to phagosomes, whereas in CD8(-) DCs, Rac1 mediates the assembly of NOX2 at the plasma membrane. In the abs...

[Article in Swedish]

A unique class of IFN-producing killer dendritic cells (IKDC) resembling natural killer cells has been defined that can recognize and lyse tumor cells through a tumor necrosis factor-related apoptosis-inducing ligand-dependent mechanism. IKDC may mediate the host-dependent antitumor activity of Gleevec/STI571 and other therapeutics that can inhibit the c-kit tyrosine kinase. IKDC represent an important new component of the innate immune system responding to cancer.

A deficit in IL-4 production has been previously reported in both diabetic human patients and non-obese diabetic (NOD) mice. In addition, re-introducing IL-4 into NOD mice systemically, or as a transgene, led to a beneficial outcome in most studies. Here, we show that prediabetic, 12-week old female NOD mice have a deficit in IL-4 expression in the pancreatic lymph nodes (PLN) compared to age-matched diabetes-resistant NOD.B10 mice. By bioluminescence imaging, we demonstrated that the PLN was preferentially targeted by bone marrow-derived dendritic cells (DCs) fo...

Conventional cancer treatments rely on radiotherapy and chemotherapy. Such treatments supposedly mediate their effects via the direct elimination of tumor cells. Here we show that the success of some protocols for anticancer therapy depends on innate and adaptive antitumor immune responses. We describe in both mice and humans a previously unrecognized pathway for the activation of tumor antigen-specific T-cell immunity that involves secretion of the high-mobility-group box 1 (HMGB1) alarmin protein by dying tumor cells and the action of HMGB1 on Toll-like receptor...

Stimulation of Toll-like receptors (TLRs) on macrophages and dendritic cells (DCs) by pathogen-derived products induces the production of cytokines, which play an important role in immune responses. Here, we investigated the role of the TPL-2 signaling pathway in TLR induction of interferon-beta (IFN-beta) and interleukin-10 (IL-10) in these cell types. It has previously been suggested that IFN-beta and IL-10 are coordinately regulated after TLR stimulation. However, in the absence of TPL-2 signaling, lipopolysaccharide (TLR4) and CpG (TLR9) stimulation resulted ...

IFN-producing killer dendritic cells (IKDC) were initially described as B220(+)CD11c(+)CD3(-)NK1.1(+) tumor-infiltrating cells that mediated part of the antitumor effects of the combination therapy with imatinib mesylate and IL-2. In this study, we show their functional dependency on IL-15 during homeostasis and inflammatory processes. Trans-presentation of IL-15 by IL-15Ralpha allows dramatic expansion of IKDC in vitro and in vivo, licenses IKDC for TRAIL-dependent killing and endows IKDC with immunizing potential, all three biological attributes not shared by B...

Human T lymphocytes can be redirected with a new defined specificity by expression of a chimeric T-cell receptor (immunoreceptor) for the use in adoptive immunotherapy of cancer. Whereas standard procedures use retroviral gene transduction to constitutively express immunoreceptors in T cells, we here explored for the first time mRNA electroporation to achieve transient immunoreceptor expression, and thereby minimizing the risk of persistence of potential autoaggression. CD4(+) and CD8(+) T cells were efficiently transfected with immunoreceptors specific for ErbB2...

Allogeneic transplantation of hematopoietic cells from an HLA-compatible donor has been used to treat hematologic malignancies. Allogeneic transplantation not only replaces the marrow affected by the disease, but exerts an immune graft-versus-tumor (GVT) effect mediated by donor lymphocytes. The development of nonmyeloablative conditioning regimens before allogeneic transplantation has allowed this therapy to be used in elderly and disabled patients. An allogeneic GVT effect is observed in a proportion of patients with renal, breast, colorectal, ovarian, and panc...

PURPOSE: Electrochemotherapy (ECT) is an effective local therapy of human cutaneous cancers but has no effect on distant untreated tumors. We addressed whether tumor-associated antigens released after ECT could induce an efficient systemic immunity when associated with an appropriate immunoadjuvant. METHODS AND RESULTS: We first studied the nature of the cellular recruitment and the expression of various toll-like receptors (TLRs) in tumors treated by ECT. We found that ECT induced a massive recruitment of CD11c and CD11b positive cells in the tumors and a strong...

A cornucopia of physiological and pathological circumstances including anticancer chemotherapy and radiotherapy can induce cell death. However, the immunological consequences of tumor cell demise have remained largely elusive. The paradigm opposing 'apoptosis versus necrosis' as to their respective immunogenicity does not currently hold to predict long-term immunity. Moreover, the notion that tumor cells may be 'stressed' before death to be recognized by immune cells deserves to be underlined. 'Eat-me', 'danger' and 'killing' signals released by stressed tumor und...

The mouse CD8alpha+ DC subset excels at cross-presentation of antigen, which can elicit robust CTL responses. A receptor allowing specific antigen targeting to this subset and its equivalent in humans would therefore be useful for the induction of antitumor CTLs. Here, we have characterized a C-type lectin of the NK cell receptor group that we named DC, NK lectin group receptor-1 (DNGR-1). DNGR-1 was found to be expressed in mice at high levels by CD8+ DCs and at low levels by plasmacytoid DCs but not by other hematopoietic cells. Human DNGR-1 was also restricted...

Tumour-associated macrophages (TAM) represent the major inflammatory component of the stroma of many tumours, and can affect different aspects of the neoplastic tissue. Many observations indicate that TAM express several M2-associated pro-tumoural functions, including promotion of angiogenesis, matrix remodelling and suppression of adaptive immunity. The pro-tumoural role of TAM in cancer is further supported by clinical studies that found a correlation between the high macrophage content of tumours and poor patient prognosis. Evidence is presented here supportin...