Little is known about the repertoire of MAGE-A3 CD4(+) T-cell epitopes recognized in vivo by neoplastic patients and how antigen processing influences epitope formation. Here, we first show that MAGE-A3-specific CD4(+) T cells are present in the blood of advanced melanoma patients. MAGE-A3(111-125), MAGE-A3(191-205), and MAGE-A3(281-300) were recognized by 7, 6, and 5 of the 11 patients tested, respectively. MAGE-A3(146-160) and MAGE-A3(171-185) were also recognized in two and one cases, whereas no recognition of MAGE-A3(161-175) and MAGE-A3(243-258) was observed...

Pancreatic carcinoma is a very aggressive disease with dismal prognosis. Although evidences for tumor-specific T cell immunity exist, factors related to tumor microenvironment and the presence of immunosuppressive cytokines in patients' sera have been related to its aggressive behavior. Carcinoembryonic Ag (CEA) is overexpressed in 80-90% of pancreatic carcinomas and contains epitopes recognized by CD4(+) T cells. The aim of this study was to evaluate the extent of cancer-immune surveillance and immune suppression in pancreatic carcinoma patients by comparing the...

Lung cancer represents one of the malignancies in which the 3 elements of conventional therapy (ie, surgery, radiotherapy, and chemotherapy) have limited effectiveness in curbing progressive disease. In this context, there is burgeoning interest in the use of vaccine therapy as a nontoxic adjunct to increase the treatment success rates over those obtained with traditional regimens alone. Several clinical trials using a variety of vaccination strategies have been reported or are ongoing. In this review, we have provided an overview of these trials, with a special ...

Clinical trials have demonstrated from time to time that cancer vaccines can elicit effective antitumour cellular immunity that may translate to clinical benefit for cancer patients. Additionally, several monoclonal antibodies currently used for treating cancer patients mediate their effects through mechanisms like antibody-dependent cellular cytotoxicity (ADCC) and therefore rely on an effective immune system. Patients with advanced tumours, however, are known to have aberrations in their immune function. Improving the clinical effectiveness of immunotherapy the...

Evidence for the existence of CLL-specific antigens recognized by the immune system can be gathered from the observation that many patients display monoclonal or oligoclonal expansions and skewed repertoire of T cells. In vitro functional studies have shown that tumor-specific T-cells are able to lyse the leukemic cells. Antileukemic cellular immunity may be boosted in vivo using dendritic cell-based immunotherapy. Our preclinical studies provide evidence that DC that had endocytosed apoptotic CLL cells (Apo-DC) were superior to fusion hybrids, tumor lysate or RN...

[Article in Swedish]

NK cells are promising effectors for tumor adoptive immunotherapy, particularly when considering the targeting of MHC class I low or negative tumors. Yet, NK cells cannot respond to many tumors, which is particularly the case for nonhematopoietic tumors such as carcinomas or melanoma even when these cells lose MHC class I surface expression. Therefore, we targeted primary human NK cells by gene transfer of an activating chimeric receptor specific for HER-2, which is frequently overexpressed on carcinomas. We found that these targeted NK cells were specifically ac...

Comment in: Mol Ecol. 2008 Jun;17(12):2793-5. Gene-expression variation in natural populations is widespread, and its phenotypic effects can be acted upon by natural selection. Only a few naturally segregating genetic differences associated with expression variation have been identified at the molecular level. We have identified a single nucleotide insertion in a vineyard isolate of Saccharomyces cerevisiae that has cascading effects through the gene-expression network. This allele is responsible for about 45% (103/230) of the genes that show differential ...

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...

The incorporation of RANTES or IL-23 into DNA vaccines may improve their immunogenicity by the recruitment and activation of dendritic cells. This may also select for a TH1 response counteracting the TH2 response which can predominate when a DNA vaccine is delivered by gene gun. We have immunized mice with various DNA constructs encoding APR/8/34 influenza virus hemagglutinin (HA), either fused to or separate from, IL-23 or RANTES using a gene gun. Those immunized with IL-23/HA fusion constructs and challenged with influenza 27 weeks post-vaccination, tended to h...

There is a growing interest in using dendritic cells (DC) for vaccine approaches in the treatment of cancer and infectious diseases. This requires a reproducible method for the generation of large numbers of DC in a closed culture system suitable for clinical use and conforming to the current guidelines of good manufacturing practices. We designed a system in which the DC were generated in a closed system from adherent monocytes using Cell Factories (DC-CF). Monocytes were enriched from apheresis products by adherence and then cultured in the presence of AB serum...

BACKGROUND: Dendritic cells (DC) are the professional antigen-presenting cells of the immune system, fully equipped to prime naive T cells and thus essential components for cancer immunotherapy. METHODS: We tested the influence of several elements (cPPT, trip, WPRE, SIN) on the transduction efficiency of human DC. Human and murine DC were transduced with tNGFR-encoding lentiviruses to assess the effect of transduction on phenotype and function. Human DC were transduced with lentiviruses encoding huIi80MAGE-A3 and murine DC with huIi80tOVA to test antigen presenta...

Antigens encoded by MAGE genes are of particular interest for cancer immunotherapy because they are tumor specific and shared by tumors of different histological types. Several clinical trials are in progress with MAGE peptides, proteins, recombinant poxviruses, and dendritic cells (DC) pulsed with peptides or proteins. The use of gene-modified DC would offer the major advantage of a long-lasting expression of the transgene and a large array of antigenic peptides that fit into the different HLA molecules of the patient. In this study, we tested the ability of gen...

AIMS/HYPOTHESIS: In the human pancreas, a close topographic relationship exists between duct cells and beta cells. This explains the high proportion of duct cells in isolated human islet preparations. We investigated whether human duct cells are a source of TNFalpha-mediated interactions with beta cells and immune cells. This cytokine has been implicated in the development of autoimmune diabetes in mice. METHODS: Human duct cells were isolated from donor pancreases and examined for their ability to produce TNFalpha following a stress-signalling pathway. Duct-cell...

An optimal anticancer vaccine probably requires the cooperation of both CD4(+) Th cells and CD8(+) CTLs. A promising tool in cancer immunotherapy is, therefore, the genetic modification of dendritic cells (DCs) by introducing the coding region of a tumor Ag, of which the antigenic peptides will be presented in both HLA class I and class II molecules. This can be achieved by linking the tumor Ag to the HLA class II-targeting sequence of an endosomal or lysosomal protein. In this study we compared the efficiency of the targeting signals of invariant chain, lysosome...

In this study, we compared dendritic cells (DCs) differentiated from positively selected monocytes (CD14-DCs) to DCs differentiated from adherence-selected monocytes (adh-DCs) with emphasis on lentiviral transduction. Using a second-generation, triple-helix containing, self-inactivating lentiviral vector at a multiplicity of infection (MOI) of 15, we observed enhanced transduction of CD14-DCs (72.8 +/- 5.3%, mean fluorescence intensity [MFI] = 166 +/- 76) compared to adh-DCs (32.3 +/- 13.1%, MFI = 119 +/- 76, n = 5). More importantly, the efficiency to transduce ...

The use of tumor antigen-loaded dendritic cells (DC) is one of the most promising approaches to inducing a tumor-specific immune response. We compared electroporation of mRNA to lentiviral transduction for the delivery of tumor antigens to human monocyte-derived and murine bone marrow-derived DC. Both lentiviral transduction and mRNA electroporation induced eGFP expression in on average 81% of human DC. For murine DC, eGFP mRNA electroporation (62%) proved to be more efficient than lentiviral transduction (47%). When we used tNGFR as a transgene we observed lenti...

Until now, studies utilizing mRNA electroporation as a tool for the delivery of tumor antigens to human monocyte-derived dendritic cells (DC) have focused on DC electroporated in an immature state. Immature DC are considered to be specialized in antigen capture and processing, whereas mature DC present antigen and have an increased T-cell stimulatory capacity. Therefore, the consensus has been to electroporate DC before maturation. We show that the transfection efficiency of DC electroporated either before or after maturation was similarly high. Both immature and...